GroupDIY

Project Specific Discussions => Filters/Equalizers => Topic started by: khstudio on December 12, 2006, 03:03:56 PM

Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on December 12, 2006, 03:03:56 PM
This is the "Nite EQ" Original thread.
I'm sorry but I had to delete several of my posts.
For the parts lists & PCB info, search for "Nite EQ" or check with Peterc... he made the PCB's for the Forum members from the info I sent him. It has it's own parts lists, Part #'s & Layout.


Quote from: peterc
Hi all
FINALLY!

(http://img.photobucket.com/albums/v318/peter_cornell2002/NightEQ.jpg)

My pots arrived from Smallbear on Friday & I put them onto the PCB & did some listening this weekend. I'm not given to over-blown descriptions, but this is a VERY nice EQ! The frequencies are great, lots of cut & boost & the air-band is very sweet at 20kHz & 40 kHz.

I will try & post some samples, but this is a keeper for me.

Can all those who want to buy PCB's please let me know, I'll post a thread on the Black Market.

http://www.groupdiy.com/index.php?topic=260973&sid=a5b8a8dd5a990b96dfca5a4debd59424#260973

Peter

Thread starts below
--------------------------------------

The company is out of business, has NO web site or support what so ever & has discontinued their products for years now. I've even heard several stories of people paying for products from the company they NEVER GOT :shock:

If anyone can help, PLEASE DO!

I'm trying to make a complete project to share with all that are interested.

It seems to be a VERY simple design.

Here is the (pre-made) power supply they use:
(I will be upgrading to a Linear PS)
http://www.ipdpower.com/catalog/product.asp?id=378 (http://www.ipdpower.com/catalog/product.asp?id=378)
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on December 12, 2006, 03:18:48 PM
It uses SMT resistors with very small numbers.... I've never had to figure them out before, HOW :?:

Also, some of them are just plain "white" are they just "zero ohm jumpers? :?

It uses :

6x 5532's
17x 1uf 63v caps
8x .1uf,
1x .22uf (seems to be on the higher bands)
1x .47uf (seems to be on the higher bands)

How do they split the bands with so little caps? :mad:

All the bands are fixed:

SUB (shelf)
40hz
160hz
650hz
2.5k

variable (shelf)=

2.5k
5k
10k
20k
40k (air)


Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on December 12, 2006, 03:30:00 PM
I have used this EQ a few times in one studio and I love the AIR and the SUB feature very much. This will be my next DIY if I can get my hands on the schematics. Great for mastering as well IMHO although it has fixed frequencies.

I want the schematics too...  [email protected]  :grin:  :green:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on December 12, 2006, 03:49:32 PM
BTW, some of the surface mont components that LOOK like resistors but are plain white, cream & pink in color have (c12, c200, c???) so they look to be SMT caps... how the hell can you tell what they are :?:  :mad:


Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: electrog on December 12, 2006, 04:02:44 PM
i have their preamp, the preq3, which developed a bad channel...long story short, i emailed "nightpro records" which seems to be some how related & got a phone number for one of the people involved in the company. i haven't had a chance to try and contact him yet. i'll pm it to you, kevin.

david
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: capnspoony on December 12, 2006, 04:21:57 PM
id be VERY interested in cloning this as well

I've been meaning to buy one for 2 years.... after I heard it

-richie

if its a simple circuit maybe pop the top and reverse engineer?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on December 12, 2006, 04:31:59 PM
I second that. Kevin, what do you say?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: capnspoony on December 12, 2006, 04:54:27 PM
its fixed frequencies with only cut/boost correct?

can't be terribly complicated

Id be interested in a pic of the inside .. how much is in that box ..

did you get my pm purusha about the NYD eq?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on December 12, 2006, 05:07:34 PM
Quote
did you get my pm purusha about the NYD eq?


I did. I am still waiting for his answer. Do you have his email address?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: capnspoony on December 12, 2006, 06:13:45 PM
poof'd
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: BR on December 12, 2006, 06:25:36 PM
anyone ever tried the patent search for this?  I would try, but I suck in finding the patents..

just a thought.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: hejsan on December 12, 2006, 07:03:19 PM
capnspoony: You better remove dave's email from the thread, this is how spammers gather addresses.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on December 12, 2006, 07:08:49 PM
capnspoony, I got the email address thanks  :wink:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Vetsen on December 12, 2006, 08:01:47 PM
Quote
It uses SMT resistors with very small numbers.... I've never had to figure them out before, HOW


SMT resistors are coded similar to color bands on a thru-hole resistor.  

4 digits usually=1%  
3 digits usually=5%

Example:
102=1K 5%
1001=1K 1%

Anything under 0603"(.060"X.030") will not be labeled.  Usually 0603 and larger jumpers are labeled 000

Quote
Also, some of them are just plain "white" are they just "zero ohm jumpers?


SMT ceramic caps are almost always not labeled.  You would have to remove the cap and measure with a LCR meter to know for sure.  Same for 0402 and smaller resistors.

Tant caps are sized "A case" "B case" etc. but usually have the same type code, or they have the actual value printed.


Vetsen
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: matthias on December 12, 2006, 09:06:03 PM
do you think dave likes spam mails...  ?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: capnspoony on December 12, 2006, 09:08:43 PM
i don't think dave will get numerous spam mail in the few hour period it took purusha to get it ..
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: solder_city on December 12, 2006, 09:22:46 PM
youd be surprised...  the spambots are very efficient. my money says dave is gonna get a bunch of spam now.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: capnspoony on December 12, 2006, 09:28:34 PM
well lets run a test

[email protected]

and i'll let it up for 2 hours

SORRY for trying to help purusha out
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: capnspoony on December 12, 2006, 09:28:45 PM
well lets run a test

[email protected]

and i'll let it up for 2 hours

SORRY for trying to help purusha out
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on December 13, 2006, 12:26:17 AM
OK, lets forget about the email BS and move on here :wink:

It's all good, I know you tried to help.

I'm about 30% thru tracing out the PCB layers & have most if not all the components down. I'm sure this is going to piss someone off but I'm not selling this thing... I may share though  :cool:

The power supply is switching TYPE, the (really expensive version) is linear... could I use something like the JLM ACDC :?:
or would it need larger filter caps than the ACDC can hold?

The rails are 18v +/-   no big deal.


K
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: capnspoony on December 13, 2006, 02:47:56 AM
can you maybe snap a pic of the inside?

I'm curious to see what's under the hood  :razz:

that's great about the tracing... I consider it "research" and you won't be selling it so trace away!

If I had one myself, I'd be doing the same thing

The only non DIY gear I have is my digi002 and an old soundcraft board

-richie
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on December 13, 2006, 03:24:25 AM
Kevin,

which ones do you have, EQ3d or EQ3?


Richie,

I got the green light from Dave so bring it on :wink:

[email protected]  (...unlimited, I have anti-spam installed)  :green:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on December 13, 2006, 03:34:48 AM


Who is Dave & what green light did he give you?

the schematic is not available

K
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on December 13, 2006, 03:43:51 AM
Quote
I have the EQ3d.


Is this one very different in sound compared to EQ3?

Quote
Who is Dave & what green light did he give you?


Oh, this is something not related to your EQ3d thread.  :wink:

Quote
But, it's not that difficult & I've got about 50% of the PCB traced out now :green:  


That is the spirit, don't stop now  :razz:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: capnspoony on December 13, 2006, 04:40:15 AM
purusha ..

sent you some stuff  :razz:

can't wait to see what you come up with .. its a great project .. i just started a spin off of it tonight .. this time im using a nice old school op amp as my output stage.  

-richie
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: mikka on December 13, 2006, 08:37:45 AM
Quote
I don't know what the laws are about reverse engineering stuff


The law is:  If a competing business (or interested DIY'er) wants to stay competitive (or interested), it's compulsory they lift the hood on any gear that interests them.

If there is a patent or registration involved, there is likely to be a small blurb on the board or product giving a number....other than that, the board design will probably be protected.

If it were a viable product, I would have expected it to be back on the market even though the original company folded.  I'd guess the market niche is too small ........
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: NewYorkDave on December 13, 2006, 08:44:35 AM
Purusha, what I sent to you is the same as what Richie has.

Guys, it would have been better to have that conversation via PM or email and not on the forum--especially not in a completely unrelated thread. (Sorry, Kevin).
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: W DeMarco on December 13, 2006, 09:58:48 AM
A buddy brought one of these babys into my studio for a project once.  What a cool piece,  Found one here at ebay

http://instruments.search.ebay.com/nightpro_Musical-Instruments_W0QQcatrefZC12QQfnuZ1QQfsooZ1QQfsopZ3QQsacatZ619QQxpufuZx

I would love to build one, they are fricken awesome.

W
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: BradAvenson on December 13, 2006, 11:46:43 AM
The EQ3d that I looked at was just band pass filters that were mixed back together giving you level control of each band.  The one I had used a switching power supply, but no surface mount parts.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: capnspoony on December 13, 2006, 11:53:34 AM
Sorry Dave, my PM box was filled at the time and couldn't sift through it until later.

KHstudio, I'm really interested with helping you on any level with this project.  

Racking up a few channels of "air" would also serve me quite well.
 
What kind of eq is it?  Active/passive?

-richie
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on December 13, 2006, 06:25:47 PM
Quote from: "BradAvenson"
The EQ3d that I looked at was just band pass filters that were mixed back together giving you level control of each band.  The one I had used a switching power supply, but no surface mount parts.


NO SM Parts in a "D" version... must have been older. All but 4 resistors are surface mount.

I've got new footprints for 1/4 watt, although the originals are 1/8 watt.

Last night was a long one... I just hope it works

(http://forum.cubase.net/phpbb2/images/smiles/eusa_pray.gif)

K
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on December 13, 2006, 06:52:01 PM
Yeah, I have tried the EQ3d version which is 1U high. The pro EQ3 version comes in 2U cases. I wonder how the EQ3 sounds.

Anyway, if we can come up with a real PCB layout for this EQ I could make a few nice cases for this DIY project as well.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on December 13, 2006, 11:40:51 PM
There's a Grayhill 2x6 switch (P# 71BF30-01-2-06S)

It's for the high shelf selection...

I NEED to find out if it's shorting Type or not. I checked the data sheets with no luck :mad: It's veryu hard to test with a meter.

I'll be using a Lorlin instead & the board will be adapted for this.

Also, ALL the caps are BOX (white in color)
I'd like to figure out what "Type" they are - Poly, Metal Poly, Poly-Prop...?
They read 1J63 & .1J63 (63v)

I'm posting some pics soon... if anybody recognises them let me know.

K
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: hejsan on December 14, 2006, 11:05:23 AM
Quote from: "khstudio"
There's a Grayhill 2x6 switch (P# 71BF30-01-2-06S)

It's for the high shelf selection...

I NEED to find out if it's shorting Type or not. I checked the data sheets with no luck :mad: It's veryu hard to test with a meter.

I think these kind of things are always shorting, I think it's a safe bet.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: electrog on December 14, 2006, 11:54:47 AM
i believe the "s" at the end of the grayhill part number denotes shorting. non-shorting types have part numbers ending in "n".

david
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on December 15, 2006, 09:36:18 PM
Deleted
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Svart on December 15, 2006, 09:44:57 PM
Quote
4 digits usually=1%
3 digits usually=5%

Example:
102=1K 5%
1001=1K 1%


this is not correct.  3 digits is USA value coding, 4 digits is euro coding.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on December 15, 2006, 10:11:45 PM
Deleted
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 11, 2007, 09:23:59 PM
Quote from: peterc
Hi Kevin

If you need help with the PCB layout for this project, let me know, I'd be glad to help out with this.

Peter

I put down this project for a bit so I could finish my 1272 NEVE. Now that's done I'd like to get back to it.

I have about 95% of the PCB Traced but want to go back & triple check ALL connections by eye & with a resistance meter to be certain.
 Then I have to make a parts/Value list to match the PCB part numbers.


Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: audioforge on January 12, 2007, 02:34:07 PM
"I'd like to figure out what "Type" they are - Poly, Metal Poly, Poly-Prop...?
They read 1J63 & .1J63 (63v) "

they looks like MKT "milfeuil" or polyester LCC .(POLYTERAPHTALATE D'ETHYLENE METALLISE)
.
audioforge
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on January 13, 2007, 04:39:05 AM
Quote
My goal is to basically build the "AIR" band & share it with the group.


Why not the whole thing?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 18, 2007, 01:34:20 AM
Deleted
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 18, 2007, 03:10:02 AM
Deleted
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on January 18, 2007, 06:13:31 AM
Quote
The schematic I'm making (for now) will only be the fixed 2.5k band & the switchable shelf = 5k, 10k, 20k, 40k.


Kevin, not bad idea at all  :thumb:

Maybe I could make some nice 2U cases for 8ch. of 2.5k band & the switchable shelf = 5k, 10k, 20k, 40k. We could organize some PCBs order and have a group buy. I know how this AIR sounds and I liked it from the first moment I heard it.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on January 18, 2007, 06:16:33 AM
Although the SUB part sound very usefull too.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 18, 2007, 07:04:26 AM
Quote from: "Purusha"
Although the SUB part sound very usefull too.


Yeah, the sub DOES sound very good :sad:

Damn you :green:

K
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on January 18, 2007, 07:13:48 AM
Let's do the SUB as well  :green:

8channels of 3 band  :thumb:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 18, 2007, 11:12:35 PM
Deleted
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 19, 2007, 12:21:13 AM
Deleted
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 19, 2007, 04:08:35 AM
Quote from: "khstudio"

I may start breadboarding just the "air" band tonite.

QUESTION:
I mentioned a few times that the circuit is parallel = 1 is the raw signal & the other EQ - the EQ pots are summed using 5.62k resistors (6 TOTAL) If I ONLY build just the "AIR" band I won't need all the summing resistors :?  BUT, won't that change the impedence :?: And how should I compensate or do I even need to :?:  :?:  :?:

Thanks,
Kevin


I'm not familiar with the exact functionality of this unit (a pic of the frontpanel would be nice, couldn't find a decent one).
But let's try: OK, so there's one 'dry' path to an output-summer and several parallel paths doing a certain frequency band ? If you only want one then no corrections needed I'd say. Since this is a pile of opamps doing filtering & summing all will be 'independent' I assume.
So just try it, I expect it'll just work.

Nice work !

Bye,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 19, 2007, 10:22:14 AM
Deleted
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Greg on January 19, 2007, 10:55:23 AM
Nice work khstudio. I'm gonna take look over this the next few days.

One thing I noticed, and it's very, very minor. It looks like you used the resistor symbol for the inductors L1 and L2. Look for a symbol that looks like a coil... looks like the primary or secondary side of a transformer symbol.

 :guinness:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 19, 2007, 10:57:22 AM
Thanks for posting this  :thumb:

Is the sum-collection-point at the top-side of R31 (@U5) ? Label might be missing.
edit: no wait, I see 'EQ-sum'. But what's U5 doing ?

Cheers,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on January 19, 2007, 03:45:12 PM
Kevin

Check your email, I've updated a lot of the parts & the schematic.

I think U5 should be an inverting amp.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 19, 2007, 06:13:09 PM
I'm in a session right now after getting about 4 hours sleep :sad:

Please post all the questions you want & I'll be back in a few hours.

I am aware that some corrections are needed.

Greg, I'll fix the inductor :thumb:

Title: do it all, baby
Post by: nielsk on January 19, 2007, 07:47:46 PM
This is a great EQ, it's the poor mans GML. Leaving out the other bands would be a mistake! Please see it through and do a full unit, I have wanted one of these for a long time and would love to be able to build myself one.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: okgb on January 19, 2007, 08:30:31 PM
Massenburg had said i believe that he put his bands in paralell
becuase it sounded better although it limited the max boost
 I have a schemo someone had made without the servos

Nice work KH
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on January 20, 2007, 02:15:15 AM
Here is an updated version with my idea of U5 - I'm open to correction....

DELETED

Changed some of the resistor values to match those on the PCB.

Quote
The stranges thing I can't figure out is the 2.5k on the high shelf & the switchable one don't seem to be using the same cap values...check it out please... but it is right.

I think they have done this to get different Q's.

I've simulated the values & they seem good for the bell bands, never sure of where the effective freq is for a shelf. The shelf EQ's are in the right ballpark though.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 20, 2007, 02:48:40 AM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 20, 2007, 04:19:29 AM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 20, 2007, 07:33:32 AM
Hi,

Nice progress!


Then this: the 'stereo-issue'.
See for instance http://www.soundonsound.com/sos/1997_articles/oct97/nightpro.html

Quote from: "SOS"
The manual also recommends using the EQ3D in mastering, broadcast, post-production, live sound and home listening systems. I have a few reservations with these last applications -- not because the unit wouldn't enhance the sound quality, because it almost certainly would have a beneficial effect -- but because there is no stereo linking facility on the controls, as mentioned earlier.

I'm not sure dual pots would guarantee this, but going for rotary switches for all bands might perhaps be a bit too much.
For a stereo air-band only this seems perfectly feasible though.

It depends of course on what applications you all have in mind.
Dual-mono or stereo ?


Bye,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 20, 2007, 08:07:13 AM
Good points.

This unit is the lower priced version (EQ3d)
It uses a switching supply
Regular pots
& no trannys

The Expensive unit (EQ3) aprox $2500-3000
Linear Power Supply
Stepped gains (ALL)
& I THINK... transformers

The circuit is the same... so there IS room for improvement.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 20, 2007, 08:18:00 AM
Quote from: "khstudio"
The question is, How can we make a board to do both, so people can have a choice.

If the pots are not to be mounted on the PCB then it's just a matter of wiring up a pot or a switch with resistors on it. (sorry for stating the obvious)
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 20, 2007, 08:23:58 AM
Quote from: "khstudio"
so there IS room for improvement.

Reading the SOS-review made me think it'd be good to add some sort of limiting of the top-top-end of the airband.
But that might spoil part of the fun of course.
Note the review is from 1997; I'm not sure how big of a problem it still is with todays converters, see below:

Quote from: "SOS"
The supplied specifications claim an overall bandwidth of 5Hz-330kHz (-3dB points),

...

Excessive boost at the top end, particularly with the AirBand set to 20 or 40kHz, can cause all sorts of horrific problems with digital recorders -- especially the earlier ones with baseband analogue anti-alias filtering. Tracks which sounded bright, crisp and full of life on the monitors during the mix often sounded absolutely terrible on replaying the DAT, because of aliasing distortions. This was caused by relatively inefficient anti-alias filtering letting a small amount of the high-level HF signals into the recorder. This breaks the Nyquist rule prohibiting audio above half the sampling rate, and the result is anharmonic distortion of the most unpleasant kind. I found an old first-generation Sony DTC1000 machine suffered the most from this phenomena, but a Sony R500 was very good in an identical situation. Modern A/D converters use a form of oversampling technology and accurate digital filtering to produce much more efficient anti-alias filtering, and the R500 proved just how much better it is!

The moral is that you should be extremely cautious with the frequency extremes. Use only very modest amounts of boost at the low end, and if your monitors don't cover the full frequency range, err towards too little! Clues to look for are meter indications that seem too loud or don't appear to relate directly to the audible programme, and loudspeaker amplifiers that get surprisingly hot or run out of steam earlier than they should. As far as the top end is concerned, the same rules apply; monitoring through your digital recorder will reveal any aliasing problems.


Bye,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 20, 2007, 09:13:45 AM
I have used this several times & haven't had a problem.

Like most EQ duties, a little goes a long way.

I would usually run the 40k at about 3-4 on the dial (at most)

Then sometimes lift the 2.5k fixed band up a nano nut for a little bit of definition.

The SUB is very cool too but damn... I've already got bass management issues.

ALL the bands are useful on this thing & very musical because the Q is so broad... a slight lift or pull here & there does wonders... it's a cool piece.
I would NEVER have spent this much time on it if it wasn't.

BTW, I've had at least 3 people try to buy mine from me in the past year for over $1000... one guy just offered me $1400 :shock:  This is the reason I started doing this project. I wanted to clone the circuit for myself & sell him mine... win, win for me :green:

Kevin

Hey Peter,
you got those boards ready yet... all this talk is getting me excited:thumb:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 20, 2007, 11:52:22 AM
1st post updated:

Faceplate, Schematic - Rev #2, Parts list

Peter,
The pots are ALL:  500k A CCW Bourns

I fixed U5... you were even closer than I thought :thumb:

I fixed the part #'s on the list (correct on the Excel file)
The only thing NOT correct on the Excel file are the 500k A CCW Bourns Pots & the missing inductors. You can use the link on page 1 to my pictures/files.

The connection on R44 (POT) was wrong (Fixed)

Part Values were added to the original schematic (NOW Rev #2)

( I will send you the NEW Original v2 schematic so you have it & can edit it with the software. Also, let me know if you need anything else traced out from the original board.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 20, 2007, 02:59:08 PM
Quote from: "khstudio"
BTW, I've had at least 3 people try to buy mine from me in the past year for over $1000... one guy just offered me $1400 :shock:  This is the reason I started doing this project. I wanted to clone the circuit for myself & sell him mine... win, win for me :green:


Keep on dreaming... before you know it that Malkjos(sp?)-dude that's cloning & selling G-SSLs has already sold an EQ-clone to that person  :twisted:

Would it be an idea to do some registration for the schematic & PCBs for this project ? Since cloning from there on seems so easy & is low in parts-cost I'm afraid quite some bad persons are tempted to make a quick buck...  :?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: haima on January 20, 2007, 07:47:50 PM
great work kevin, peter and everyone, thanks for sharing!

i don't have much to offer as i don't have a eq3d (nor have i even seen one in the flesh..) but i've heard good things and can't wait to try the circuit out when i have a spare hour or two (mmm, yeah right!)

frequency selection is always a compromise with a fixed eq (and not having used the unit i don't know how it sounds) but i imagine having access to some extra frequencies, such as around 60Hz and 450Hz etc, might be useful - we could experiment with  adding some extra switchable freqs...

anyway... i better butt out now, keep up the good work!  :sam:

haima

oh, here's some evilbay links with some pics and info for those who don't have one of these units:

eq3-d ebay - with pics (http://cgi.ebay.com/Nightpro-Night-Pro-EQ3D-EQ3-D-Dimensional-equalizer-eq_W0QQitemZ220054558367QQihZ012QQcategoryZ23788QQcmdZViewItem)

eq3-d ebay - with a copy of a magazine review (http://cgi.ebay.com/NTI-EQ3-D-NightPro-Professional-Equilizer-Like-New_W0QQitemZ330037398008QQihZ014QQcategoryZ23788QQcmdZViewItem)
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 20, 2007, 09:42:59 PM
Quote from: "clintrubber"
Quote from: "khstudio"
BTW, I've had at least 3 people try to buy mine from me in the past year for over $1000... one guy just offered me $1400 :shock:  This is the reason I started doing this project. I wanted to clone the circuit for myself & sell him mine... win, win for me :green:


Keep on dreaming... before you know it that Malkjos(sp?)-dude that's cloning & selling G-SSLs has already sold an EQ-clone to that person  :twisted:

Would it be an idea to do some registration for the schematic & PCBs for this project ? Since cloning from there on seems so easy & is low in parts-cost I'm afraid quite some bad persons are tempted to make a quick buck...  :?


What does that mean DUDE :?  "Keep on Dreaming"
If my plans were to make money I would NEVER have posted it in here.
I thought some of you guys may enjoy the project as much as me... If it becomes a problem I'll just pull all the info & schematics.

The "REAL EQ3d's" sell for over $800 at least on eBAY & don't show up too often. My plans are to clone for myself, share, then sell my original unit.

I know nothing about
Quote
registration for the schematic & PCBs


I DO NOT want to get in the middle of any BS over this.

Should I put a "Gyraf" style disclaimer on the 1st post :?:

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 21, 2007, 03:19:06 AM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: chrissugar on January 21, 2007, 03:42:06 AM
Kevin,
the decoupling capacitors for each opamp are important to be connected close to the + and - pins of each opamp. In  your PCB picture the decoupling caps are close to the opamps but the ones on the negative rail are connected to one trace and the opamps to another so they don't do what they are supposed to do.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 21, 2007, 04:03:56 AM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: chrissugar on January 21, 2007, 04:19:36 AM
Wow :shock:  It makes no sense. Are you sure there are no traces under the opamps on the component side that connect the decoupling direct to the opamp pins? Even if that would be the case it looks strange to have two separate traces for the minus rail.  :?

chrissugar
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 21, 2007, 06:56:35 AM
Quote from: "khstudio"
Quote from: "clintrubber"
Quote from: "khstudio"
BTW, I've had at least 3 people try to buy mine from me in the past year for over $1000... one guy just offered me $1400 :shock:  This is the reason I started doing this project. I wanted to clone the circuit for myself & sell him mine... win, win for me :green:


Keep on dreaming... before you know it that Malkjos(sp?)-dude that's cloning & selling G-SSLs has already sold an EQ-clone to that person  :twisted:

Would it be an idea to do some registration for the schematic & PCBs for this project ? Since cloning from there on seems so easy & is low in parts-cost I'm afraid quite some bad persons are tempted to make a quick buck...  :?


What does that mean DUDE :?  "Keep on Dreaming"

Hi Keven,

That 'Keep on dreaming... ' wasn't meant like you have understood it. It's the wording I used after seeing yet another G-SSL-clone by that Malkjos-person and I think it'd be a real pity if the reversed engineered circuits & upcoming PCBs would fall into his greedy hands as well.

So that 'Keep on dreaming... ' was partly out of fustration about that G-SSL-eBay-mass-producer and was partly in jest. So my words may have given you a wrong impression of what I was meaning, I regret that and let me add my apologies for the part of the confusion that's to blame on me.

Quote
If my plans were to make money I would NEVER have posted it in here.
I thought some of you guys may enjoy the project as much as me... If it becomes a problem I'll just pull all the info & schematics.

That's all clear, you're not after a quick buck and you selling your original unit later on is in no way objectionable of course.

Quote
I know nothing about
Quote
registration for the schematic & PCBs


I DO NOT want to get in the middle of any BS over this.

My main point was that since this unit seems to have such a high ratio of desirability vs ease & low cost of making (after the hard work of tracing & PCB-making), I'd really hate to see it going the route the G-SSL-PCBs have gone for Malkjos-types.
What could be done about that ?

Quote
Should I put a "Gyraf" style disclaimer on the 1st post :?:


While it won't guarantee much I'm afraid, I still think it's a good idea. At least it gives something to point at once the quick-buck-clones start appearing on eBay.

Best regards,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 21, 2007, 07:31:58 AM
The more I thought about it I thought you may be just venting  "in General"

Ya... all that work for that would suck :mad:

I just spent another night working on it... still waiting to hear from Peter about his progress & opinions... I think he's working on the FULL PCB :wink:

We'll see.

Send me your email & I'll send you all the current files... like the raw PCB files so you can see what's up & or etch your own. There are some extras missing in the schematic that you can see on the original (cloned) PCB.

I would recommend that anyone who takes these files remember... it may NOTE be %100 but SHOULD be very close. You can help by using the MAIN PCB file, parts list & Schematic to reference the project & find errors, if any.

I'd like to see a group effort for a new cool easy EQ :grin:

Thanks, Peter (#2)
Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 21, 2007, 08:58:56 AM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: okgb on January 21, 2007, 10:06:20 AM
Thanks for sharing your work & effort Kev , i appreciate it

I'm in for a board if anyone is making some ,

regards Greg
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MrZpliff on January 21, 2007, 11:15:49 AM
Quote from: "okgb"
Thanks for sharing your work & effort Kev , i appreciate it

I'm in for a board if anyone is making some ,

regards Greg


Me too !

Great job on this one  :thumb:  :thumb:  :guinness:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 22, 2007, 02:32:36 AM
I'm getting set up for etching right now so well see if this thing works pretty soon... wish me luck  :green:

I did fix the errors & will repost the PCB.

Is a CCW Audio pot a Reverse Audio Taper :?:  :?:  :?:


Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on January 22, 2007, 03:14:38 AM
Quote
Is a CCW Audio pot a Reverse Audio Taper


Probably not, the taper is usually specified after the value. You said the value was 500kA, the A value is log taper usually. O dont know where the CCW comes from. Is it printed on the pot?

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: chrissugar on January 22, 2007, 03:40:53 AM
The sure way to determine what type of pot is, is to use an ohm meter.
Put the pot in exact mid position and measure the resistance between wiper and the left end then between the wiper and the right end.
1-If values are equal, there is a linear pot.
2-If the left side is 10% of the total value of the pot and the right side is 90% it is a log pot.
3-If the left side is 90% of the total value of the pot and the right side is 10% it is a reverse log pot.

chrissugar
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 22, 2007, 03:43:42 AM
Quote from: "peterc"
Quote
Is a CCW Audio pot a Reverse Audio Taper


Probably not, the taper is usually specified after the value. You said the value was 500kA, the A value is log taper usually. O dont know where the CCW comes from. Is it printed on the pot?

Peter


I looked up the Bourns part #'s & codes & that is what it said.

It sure sounds like reverse taper...

The part # on the Bourns POTS are:
91A1DC24T23

The part # on the Switchable high shelf is:
91C1DD20T23

Please check it out... they have a PDF with the codes... Mouser, Digikey.

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MrZpliff on January 22, 2007, 04:26:56 AM
Quote
I looked up the Bourns part #'s & codes & that is what it said.

It sure sounds like reverse taper...

The part # on the Bourns POTS are:
91A1DC24T23

The part # on the Switchable high shelf is:
91C1DD20T23

Please check it out... they have a PDF with the codes... Mouser, Digikey.

Kevin


I agree, as I looked up Bourns-site too, I'm pretty shure a CCW-pot is a reverse-taper pot...
the Gyraf Calrec EQ uses reverse audio pot's.
I haven't checked but it may wor´k in a similar way  :?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 22, 2007, 04:36:22 AM
I hope they're available without too much BS :?

When it comes to the film CAPs... what do you think we should use :?:

I JUST noticed an "AV" on the side if one of the films... Brand maybe?

I wish I knew the real type but I agree with Peter, If we use good caps it will be fine :thumb:

I STILL would like to know what the purpose is of the 10watt 150 ohm resistor from the positive 18v rail to GND??? :?
You can see it on the original PCB file NOT the schematic!

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: chrissugar on January 22, 2007, 04:59:05 AM
decoding the 91A1DC24T23

91-MODEL-single turn in line PC pins
A-BUSHING-metal plain 3/8"
1-SECTIONS-single
D-ANTIROTATION LUG-no lug
C-SHAFT TYPE-1/4"
24-SHAFT LENGTH-3/8"
T-ELEMENT TYPE TAPER- CCW audio
23-RESISTANCE-500Kohm

So this is a 500K revlog pot

decoding the 91C1DD20T23

91-MODEL-single turn in line PC pins
C-BUSHING-metal plain 1/4"
1-SECTIONS-single
D-ANTIROTATION LUG-no lug
D-SHAFT TYPE-1/8"
20-SHAFT LENGTH-5/8"
T-ELEMENT TYPE TAPER- CCW audio
23-RESISTANCE-500Kohm

this is also a 500K revlog pot but with different mechanical dimensions.

I have the feeling that it will be easyer to make this with a rotary switch (12 position Lorlin) with resistors than finding 500K revlogs.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MrZpliff on January 22, 2007, 05:07:56 AM
Quote from: "chrissugar"

I have the feeling that it will be easyer to make this with a rotary switch (12 position Lorlin) with resistors than finding 500K revlogs.


I think that's a good idea if you want to use it as a stereo-master EQ...
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 22, 2007, 05:08:06 AM
I RE-UPLOADED THE PCB WITH THE CORRECTIONS
(in the above post)   HERE's a link also:
http://www.twin-x.com/groupdiy/albums/userpics/3d_air_eq_-_Top_Q_v1_fixed.jpg
http://www.twin-x.com/groupdiy/albums/userpics/3d-air-eq---Top-Q-v1sw.jpg

Yea, the "AIR" pot has a tiny shaft...that's all.

About the stepped gains:
I NEVER went higher than about 2:00 or too much lower than 10:00 on the gain controls.

The air only goes up & I've went as high as HALF... no more.

OK, I'm packin a bowl & headin out in the snow to the shop...I got etching to do :green:

If you guys spot any errors in the Re-Posted PCB (high shelves only vers)
PLEASE let me know SOON before I print it.

Also, I don't have the Inductors for the output... hopfully thy won't matter for testing :?

Thanks,
Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 22, 2007, 10:01:51 AM
Keven, I'm curious to which program you are using for the schematic.
Drawing-style of that software looks neat.  :thumb:
Are there any direct transfers to a simulation program possible perhaps?


Then this:

Please allow me some thinking out loud w.r.t. the circuit
(v2 of the first page):

When the EQ is engaged, all bands are in parallel and have a
max gain of '20dB minus something'  (so that'll result in the
15dB of the max boost). Outside that region each section is unity gain.

So the 'EQ-engaged but flat' setting is realized by all those
500k no-center-detent CCW-pots in their mid-setting, a situation
that likely won't ever exactly be the case.

That'll be fine of course, if you want flat then simply don't insert or
engage the EQ.
And reportedly this is a mighty fine sounding EQ so why worry ?

But it's surprising me a bit for a device that's also intended as a mastering EQ.
I mean, the mastering-version has the switched level-pots so
exact levels are realizable.
But do all those EQ-bands also line up decently even when the level-pots
are optimally adjusted ?

Has anybody done a simulation yet for the complete circuit ?
For a 'flat-but-EQ-engaged' setting I expect there'll still be a slight ripple,
especially in practice when there are unavoidable component tolerances.

As said, it won't matter but it came to mind when trying to understand
what's happening here in this circuit.



Cheers,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: chrissugar on January 22, 2007, 10:29:03 AM
I had exactly this thought Peter.
I was expecting the pots to be linear and at exact mid position the resitance to be the value for 0dB, but with antilog pots it looks like there is no chance with the eq bands engaged, but at 0B position to have a flat response.
This is one of the reasons why I think about a switch. For mastering with a 12 step Lorlin, 0.5dB/step you can cover 6dB (in mastering normaly there is no need for more) For mixing,with 1dB/step you can cover 12dB (plenty enough)

chrissugar
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 22, 2007, 10:46:10 AM
Quote from: "chrissugar"
I had exactly this thought Peter.
I was expecting the pots to be linear and at exact mid position the resitance to be the value for 0dB, but with antilog pots it looks like there is no chance with the eq bands engaged, but at 0B position to have a flat response.
This is one of the reasons why I think about a switch. For mastering with a 12 step Lorlin, 0.5dB/step you can cover 6dB (in mastering normaly there is no need for more) For mixing,with 1dB/step you can cover 12dB (plenty enough)

chrissugar

Hi ,

Chris, those switches look like a nice approach. 'Unfortunately' they need to be 'CCW' indeed, just like the pot in an API 312-type of circuit needs to be for controlling gain.

But that's only one thing - even with optimally aligned controls there still could be that 'ripple' that you see for instance when all bands of a graphic EQ are full-on or full-off: They don't realize a ruler-flat response.
And the EQ of this thread might have it already in its neutral-setting.

Again, FWIW all this - since many ears have already confirmed this is a very nice EQ (so to #&*% with technical objections).
But obviously we're here not only to get some boxes to make music, we're technically interested as well. So because of that I brought this up.  

Cheers,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 22, 2007, 11:06:10 AM
Good points... I never thought about the taper & the mid position... I've been so wrapped up in just getting the circuit right for us to learn & build.

The more expensive version used stepped gains (EQ3)
Try doing a search for these & there should be some of the original articals & tech stuff somewhere so you can get a better idea what it's all about.

I'm just happy I got to this point. :green:

I finished the photo process on my boards this mornig & I'm heating the tank for etching now so if I have enough energy well see if it works pretty soon.
(http://forum.cubase.net/phpbb2/images/smiles/eusa_pray.gif)

I don't have the exact pots but a linear should work for testing...
Same thing with resistors... I may be missing some values but I'll just string some together for now if I have to.

Hey, a simple "OFF" switch could shut the bands off too NO :?:

I'll tell ya, when all the pots are straight up & you flip the bypass on & off there isn't much change if at all that's noticable.

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 22, 2007, 11:11:54 AM
Quote
Keven, I'm curious to which program you are using for the schematic.
Drawing-style of that software looks neat. Heck Yeah!
Are there any direct transfers to a simulation program possible perhaps?


(KEVIN) :wink:

www.expresspcb.com (it's free)

I'm not sure if you guys have the latest files or any at all but go get that software & you can print & etch yourself if you want. You NEED the software to do it. (single sided - green traces are where the jumpers go.)

Peter (Green pre) DID run some simms & said that it all worked.

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 22, 2007, 11:18:00 AM
Quote from: "khstudio"
I've been so wrapped up in just getting the circuit right for us to learn & build.
:thumb:

Quote
Try doing a search for these & there should be some of the original articals & tech stuff somewhere so you can get a better idea what it's all about.

Do you know if someone has already scanned some stuff out of the manual ? I saw that manual on eBay coming by, but it has been closed by now.

Quote
I'm just happy I got to this point. :green:

All fine ! I mean, you're doing all the hard work and we here sit back, enjoy a cigar and mumble a bit about the circuit  :twisted:  :green:  :thumb:  

Quote
Hey, a simple "OFF" switch could shut the bands off too NO :?:

You mean disconnecting some sections from the summing point ? No, that will interrupt that frequency region.
As I understand the circuit it NEEDS the 'neutral'-setting of the CCW-pot to have 0dB for a certain frequency range.
Disconnecting a section completely will punch a hole in the freq. response, even a bit more than the max-cut would do.

Quote
I'll tell ya, when all the pots are straight up & you flip the bypass on & off there isn't much change if at all that's noticable.

Kevin

'Straight up' = in the neutral position ? Could well imagine that; the ripple might be measurable and noticable in very controlled listening environments, but for about all other cases little influence might be experienced. Which means that the combining of the bands is done well, but I was surprised that they took that approach.

Cheers,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: chrissugar on January 22, 2007, 11:25:19 AM
Quote from: "clintrubber"

Chris, those switches look like a nice approach. 'Unfortunately' they need to be 'CCW' indeed, just like the pot in an API 312-type of circuit needs to be for controlling gain.


Don't forget that this is not a potentiometric circuit (divider), it is a variable resistor, so there is no need to make a chain of resistors. You can use one separate resistor for each step, which is much easyer.  :grin:

chrissugar
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 22, 2007, 11:31:33 AM
Quote from: "chrissugar"
Quote from: "clintrubber"

Chris, those switches look like a nice approach. 'Unfortunately' they need to be 'CCW' indeed, just like the pot in an API 312-type of circuit needs to be for controlling gain.


Don't forget that this is not a potentiometric circuit (divider), it is a variable resistor, so there is no need to make a chain of resistors. You can use one separate resistor for each step, which is much easyer.  :grin:

chrissugar

Indeed ! Either as say 12 separate resistors to a common point or as an incremental chain.
I've briefly been thinking about an easy trick to get 12 boost & 12 cut positions from one cheap Lorlin by means of adding a 'boost/cut'-switch but that won't be too easy I'm afraid because of the 'bent law' required  :?  

Bye,

 Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: chrissugar on January 22, 2007, 11:35:46 AM
Quote from: "clintrubber"

Quote
Hey, a simple "OFF" switch could shut the bands off too NO :?:

You mean disconnecting some sections from the summing point ? No, that will interrupt that frequency region.
As I understand the circuit it NEEDS the 'neutral'-setting of the CCW-pot to have 0dB for a certain frequency range.
Disconnecting a section completely will punch a hole in the freq. response, even a bit more than the max-cut would do.


And this is the exact reason why you can't build an EQ like this with just one or two bands. You need to have all the bands to leave the rest of audio untouched.

Kevin, you can do a test.
Desolder the resistors in series with the pots of each band except the air band, and listen what it does.
it would be interesting to do this with each band, and listen to it's sound.

chrissugar
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 22, 2007, 11:39:17 AM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 22, 2007, 11:50:10 AM
Quote from: "khstudio"
Also, do you think I/we will have to compensate (impedence/load) when removing some bands like I have :?:

Kevin

As it looks like so far they all NEED to be there, so there's no issue of compensating missing bands...  as far as changing impedances go...
You could of course 'correct the topology' for missing bands but then better duplicate the whole circuit I'd say.

On the other hand, I can see how the air-band could be used as a stand alone thing when used in say a subgroup insert. You do your main-mix as usual and route some channels to the subgroup as well. The subgroup-faders control the added air.

Or even better yet, use it like you would a reverb, so with FX-sends from the channels. Receive the result on an FX-return.
(Check topology for signal-polarity).

Bye,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 22, 2007, 11:53:27 AM
I think you guys are right... & I thought it myself :mad:

Please look at the schematic for me & tell me how to make the FIXED 2.5k band FULL band & cover everything under the "AIR" (switchable shelves)

At least I'll have that which is the best part anyway. (this is just for now with the boards I just made.

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 22, 2007, 12:04:25 PM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 22, 2007, 12:43:35 PM
Don't leave me now :green:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on January 22, 2007, 01:34:28 PM
Ah, just copy the damn thing to the bones  :green:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 22, 2007, 01:40:55 PM
Quote from: "Purusha"
Ah, just copy the damn thing to the bones  :green:


I never said I wouldn't... just wanted to make a simpler version... that's all.

It's been a very long & frustrating day. Thank god my other 1272 etched good but I don't think I left the EQ board under the lamp long enough... it's not looking good.

I WILL be doing the full... gone too far to stop now.

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on January 22, 2007, 02:38:59 PM
Kevin

You could probably run a resistor in parallel to the single band you wanted to use. Actually a pot would be better for testing purposes, then you could vary the pot to find the value that gives the same signal amplitude to the EQ band you want to use.

Then take the pot out of circuit, measure its value & sub in a resistor.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on January 23, 2007, 03:08:00 AM
I'll have a go at this...

Quote
I see that the input splits - unafected (+) swing ends up at U4 then PIN 2 (+)


R4 on the input opamp just goes to ground. Confusing the way it has been drawn, but no signal goes to the output via this path. The audio path is all via the output of this opamp, from pin 1, through both the "bypass" path, & the "to all Q's" path.

Then the relevant path is selected by SW7 & routed to the - input of U5. U5 & U4(b) then act as the output buffers & balancing cct.

I will try & run a sim tonite to determine the value of the "bypass" resistor, it might have to be an all-pass opamp stage.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 23, 2007, 03:32:35 AM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 23, 2007, 05:18:20 PM
I got one board almost loaded but left out the U1b section... waiting for advise.

What's the word :?:

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 24, 2007, 09:07:37 AM
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Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MrZpliff on January 24, 2007, 09:25:51 AM
Quote from: "khstudio"
:sad:

I'm pretty bummed out... I was hoping for a lot more help & interest in this project.


 :sad:  Sad to say I simply doesn't have the knowledge to help you, but I'm very interrested and willing to support you in any way I can (whatever that may be)

atleast I'll try to cheer ya up !  :thumb:  :thumb:  :thumb:  :guinness:  :guinness:  :green:  :grin:  :green:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: gar381 on January 24, 2007, 09:45:46 AM
Kevin

Hang in there... :thumb:

I think there is a lot of interest in this.  Lots
of us are following this thread.  Please keep
up the good work!

GARY
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: chrissugar on January 24, 2007, 11:29:15 AM
Kevin,

You can spare yourself alot of time and effort if you try what I asked you. Desolder all the resistors in series with the pots except one band , and listen to what it does (how it measures and how it sounds) at minimum, mid and maximum position. Do it with all bands, and you will draw the right conclusions.
Of course, you can simulate the circuit or we can speculate but nothing compares to some real world data.

chrissugar

P.S. I'm sorry I don't have the time to be actively involved in this project. I would really like to help more than giving just some ideas.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 24, 2007, 02:46:04 PM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on January 24, 2007, 03:37:54 PM
I'm tied up at the moment, but try this. To make the hi shelf an all pass stage, just short out C51 & C3. Should make it a non-inverting amp with a gain of about 8.

But I think one of the previous posts is right about a single band will work. In the sim, it looks like a single band will actually pass the audio above & below the peaks made by the caps. I have only simulated a single band without the summing parts, but have a look at the pic.

I know circuitmaker has been critisized here before, but it looks pretty convincing......

(http://img.photobucket.com/albums/v318/peter_cornell2002/Air-band.gif)

Hope it helps

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 24, 2007, 04:37:23 PM
I'm about an hour or less from firing it up :grin:

Thanks Peter,

Just wondering... will it work OK the way I designed it too???

Your idea definitly sticks to the original more & seems much easier. :thumb:
 

Kevin
Title: Air EQ
Post by: Harpo on January 24, 2007, 04:57:12 PM
Hi Kevin,

some input to your hard work (hoping it is useful). :thumb:

your summing resistor R37 is part of the summer U5. Increase R37 to 56k to set this inverting stage to AV = -1. (AV=-R30/R37).

The modified Full Band will need an AV of about 10 to behave as your airband so R11 at 10k and R9 at 1k will set this AV. (AV=1+(R11/R9))

The full schemo has a minor error at R47. This resistor is switched in parallel to R26 when in Balanced mode and C14 can block DC offset.

For usual the 22pF C13 is a compensation cap and for NE5534 (U5) close between pin 1 and 8 (trace-side?) or use this cap as shown in the feedback path for the dual NE5532 witch has no compensation pins.

The 2.5k shelf band is drawn as 1.2k shelving, so leave out C51 or set C3 and C51 to 470nF each. (-3dB hpf = 1 / (2pi * R9 * C3||C51).

Calculating from your shemo the airbands are at 2kHz, 4kHz, 8kHz, 17kHz and 36kHz, so a bit off the frontpanel labeling, may be correct with real world caps.

all the best
Harpo
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 24, 2007, 05:10:05 PM
Quote from: "peterc"
But I think one of the previous posts is right about a single band will work. In the sim, it looks like a single band will actually pass the audio above & below the peaks made by the caps.

Yep, all those amps for the indiv. bands are non-inverting so the gain outside of 'the filtered band of interest' can never be less than unity (0 dB)  

(as long as they're configured with some kind of negative feedback)

Bye,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 24, 2007, 05:17:20 PM
Quote from: "khstudio"
but I had this idea of the AIR band only version from the start & now I have to stop & learn which is always a good thing.

Did you catch what I wrote last Monday ?
Quote from: "clintrubber"

...
On the other hand, I can see how the air-band could be used as a stand alone thing when used in say a subgroup insert. You do your main-mix as usual and route some channels to the subgroup as well. The subgroup-faders control the added air.

Or even better yet, use it like you would a reverb, so with FX-sends from the channels. Receive the result on an FX-return.
(Check topology for signal-polarity).

Bye,

Peter


So the straigh-on dry path is provided by your mixing-desk...
...for the time being, or as a permanent way of using the air-band. The latter will mean the dry signal doesn't need to leave & enter your mixer.

Bye,

  Peter
Title: Re: Air EQ
Post by: khstudio on January 24, 2007, 06:10:30 PM
Quote from: "Harpo"
Hi Kevin,

some input to your hard work (hoping it is useful). :thumb:

your summing resistor R37 is part of the summer U5. Increase R37 to 56k to set this inverting stage to AV = -1. (AV=-R30/R37).

The modified Full Band will need an AV of about 10 to behave as your airband so R11 at 10k and R9 at 1k will set this AV. (AV=1+(R11/R9))

The full schemo has a minor error at R47. This resistor is switched in parallel to R26 when in Balanced mode and C14 can block DC offset.

For usual the 22pF C13 is a compensation cap and for NE5534 (U5) close between pin 1 and 8 (trace-side?) or use this cap as shown in the feedback path for the dual NE5532 witch has no compensation pins.

The 2.5k shelf band is drawn as 1.2k shelving, so leave out C51 or set C3 and C51 to 470nF each. (-3dB hpf = 1 / (2pi * R9 * C3||C51).

Calculating from your shemo the airbands are at 2kHz, 4kHz, 8kHz, 17kHz and 36kHz, so a bit off the frontpanel labeling, may be correct with real world caps.

all the best
Harpo


Awesome :thumb:  :green:

#1
You are right about R47. I rechecked it against the REAL PCB. I will fix that ASAP.

#2
I do not think U1 is an inverting stage :? 5 I think is... how would raising that value affect the other summer from the AIR BAND (5.6k)???

#3
C13 does NOT connect to pins 1 & 8 on the PCB... not sure what you mean there???
Quote
The modified Full Band will need an AV of about 10 to behave as your airband so R11 at 10k and R9 at 1k will set this AV. (AV=1+(R11/R9))

Will my NEW setup that I drew (posted above) work? I already hooked it up but I can change it if need be. With the 100k pot maxed & 10k resistor to GND should give me 10x right?

If you don't have the PCB I drew of the REAL EQ3d I will send you the file & you can open it with the free software www.expresspcb.com.

THANK YOU for getting involved... I am very excited about this project... when you guys get involved it gives me a jolt to keep going.

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 24, 2007, 06:14:56 PM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 24, 2007, 06:27:10 PM
Cool, enjoy ! :thumb:



Quote from: "khstudio"

I'm an eager student

Kevin

Even more  :thumb:


BTW, I like the drawing style of your schematics better than what I use (Simetrix). So I'm curious, which program are you using ?

And can you run a circuit simulation from it (either directly or after some exporting of the netlist).

Thanks,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 24, 2007, 06:31:24 PM
Quote from: "clintrubber"
Cool, enjoy ! :thumb:



Quote from: "khstudio"

I'm an eager student

Kevin

Even more  :thumb:


BTW, I like the drawing style of your schematics better than what I use (Simetrix). So I'm curious, which program are you using ?

And can you run a circuit simulation from it (either directly or after some exporting of the netlist).

Thanks,

  Peter


No Simm... but it's free. PCB & Schematic software www.expresspcb.com.

Can you comment on wether my redesign of that stage I posted will work or not???
Also, I'm not sure of a couple thing that Harpo said although I think he know a thing or 2 :green:

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 24, 2007, 07:19:15 PM
Quote from: "khstudio"
No Simm... but it's free. PCB & Schematic software www.expresspcb.com.

Thanks for the link. Hmm, bummer we can't go to a simulator directly from there. Simetrix-circuit-drawing are fine but could be better. Does sim of course, but no PCB. I'll try the sch-side of ExpressPCB

Must have a further read of all the new stuff above before I can comment.

Bye,

  Peter
Title: Re: Air EQ
Post by: Harpo on January 24, 2007, 08:48:49 PM
Quote from: "khstudio"

#2
I do not think U1 is an inverting stage :? 5 I think is... how would raising that value affect the other summer from the AIR BAND (5.6k)???


This is what I tried to show. R35 or better said R34 in series with R35 is the input resistor of the summer U5. (Pin2 of U5 is the summing node) This Rin has a value of 5.6k for max boost up to 506.6k for lowest amplification. (AV=-Rf/Rin = -56.2k/505.6k up to -56.2k/5.6k). U1 for shure is non inverting. You only have 1 summer (U5) and both paths from airband and fullband add up. If you don't want to go the well thought way clintrubber described, this may be a compromise.

Going thru the stages you get AV=0.5 at U4(input), AV=0.1 at the voltage divider R25/R24, AV=10 at U1, AV=-1 at U5 and AV=-2 at U4(output), so your total voltage gain is 1 for your fullband. The airband adds up its +-20dB, so overall gain is always more than 1 above airband.

Just another idea:
Changing your fullband to lowpass with a cap across R11 will catch this. The cap value would be switched with another deck of SW1 and set to the same -3dB frequency as your airband. (C-lowpass=1/(2*pi*R11*freq)).
Setting R11 to 10k the values for C across R11 will be
switch-pos. 2.5khz airband -> C=8nF
switch-pos. 5khz airband -> C=4nF
switch-pos. 10khz airband -> C=2nF
switch-pos. 20khz airband -> C=940pF
switch-pos. 40khz airband -> C=440pF
switch-pos. OFF airband -> C=leave out
If you want R11 100k (your pot), divide previous cap values by 10

Quote from: "khstudio"

#3
C13 does NOT connect to pins 1 & 8 on the PCB... not sure what you mean there???


Some brands of NE5534 tend to hf-oscillating when not compensated. A 22pf cap between pin 5 and 8 prevents this. Sorry for typo pin 1.
http://focus.ti.com/lit/ds/symlink/ne5534a.pdf

Quote from: "khstudio"

Will my NEW setup that I drew (posted above) work? I already hooked it up but I can change it if need be. With the 100k pot maxed & 10k resistor to GND should give me 10x right?

It will work, but may generate more offset and noise, but we're already at line level. If you add the lowpass cap, these get f**ing small at 100k.

close to 3am - time for bed
all the best
Harpo
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 24, 2007, 10:06:39 PM
IT WORKS :razz:

x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: BR on January 24, 2007, 11:09:29 PM
Hi Kevin,

Bourns pots actually describe their Rev Log as CCW log.  If you want what you described, you need to order a CW log and wire it reversed.  

peace
Gil
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 24, 2007, 11:40:18 PM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 25, 2007, 01:17:50 AM
That damn 150 ohm 10 watt (I found one) is cooking too :mad:

What the hell... something with that thing doesn't seem right.

Do you guys think it's needed. I rechecked the original & it's there... but that was with a switching power supply... don't know but it's way too hot.

I will try to make some samples but it won't be for a few days.


Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on January 25, 2007, 03:36:11 AM
Hey Kevin. Great work! I see it's going nicely towards the new DIY project  :thumb:
I am also glad we can use Mnats PSU boards as I have a bunch of them at home  :wink:

Can't wait to see the final layouts and all. Keep up the good work.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MrZpliff on January 25, 2007, 04:08:01 AM
Great Job !  :thumb:

Are the schemo correct ?

would be nice to have the option to build the full EQ or just the "air"
on the same pcb I think.... would be possible I guess...
Title: air eq
Post by: Harpo on January 25, 2007, 06:24:32 AM
Quote from: "khstudio"
That damn 150 ohm 10 watt (I found one) is cooking too :mad:

What the hell... something with that thing doesn't seem right.

Do you guys think it's needed. I rechecked the original & it's there... but that was with a switching power supply... don't know but it's way too hot.

I will try to make some samples but it won't be for a few days.


Kevin

leave it out or replace it with a smoothing cap. It's not needed for linear supplies in this case. This R pulls 0.12 A as a min load for the switching supply.
Nice to hear it is working as desired.
 :thumb:
You won't need the inductors on output for testing.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 25, 2007, 01:55:16 PM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 25, 2007, 03:51:29 PM
500k reverse Audio Taper Pots

Please help if you have a source with a decent price :!:

These can get expensive :mad:

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on January 25, 2007, 04:04:55 PM
OK, who wants some 3D EQ cases  :green:

No seriously, I would really like to DIY a few channels of this great EQ and put them in a nice racks :razz:

Hey Kevin, so it's all ready to rock'n roll?  If the full PCB layout is ready I would like to have it for sure.

Please send it to my email and  thanks for doing this.  :thumb:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bellyflop on January 25, 2007, 04:06:22 PM
Quote from: "khstudio"
500k reverse Audio Taper Pots
Please help if you have a source with a decent price :!:
What are you looking to spend?  Small Bear has them (http://www.smallbearelec.com/Detail.bok?no=116).
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 25, 2007, 04:45:46 PM
Quote from: "bellyflop"
Quote from: "khstudio"
500k reverse Audio Taper Pots
Please help if you have a source with a decent price :!:
What are you looking to spend?  Small Bear has them (http://www.smallbearelec.com/Detail.bok?no=116).


EXCELLENT :thumb:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 25, 2007, 04:51:51 PM
Quote from: "Purusha"
OK, who wants some 3D EQ cases  :green:

No seriously, I would really like to DIY a few channels of this great EQ and put them in a nice racks :razz:

Hey Kevin, so it's all ready to rock'n roll?  If the full PCB layout is ready I would like to have it for sure.

Please send it to my email and  thanks for doing this.  :thumb:


I need to adjust the  PCB just a little then I'll send it out :wink:

Hang in there.

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on January 25, 2007, 05:33:39 PM
Quote from: "bellyflop"
Quote from: "khstudio"
500k reverse Audio Taper Pots
Please help if you have a source with a decent price :!:
What are you looking to spend?  Small Bear has them (http://www.smallbearelec.com/Detail.bok?no=116).



Hey, is this the same thing?

http://www.banzaieffects.com/Alpha-16mm-FS-500k-REV-log-pr-17321.html
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 25, 2007, 05:36:36 PM
More Testing:

SM58, NEVE 1272 to balanced line in on board (Topaz Project 8)
Using the insert point to insert EQ (unbal) for testing & pulling for true BP listening -

For the hell of it I decided to do a comparison against my boards EQ (which I never thought was too bad... usable actually in moderation) & I was shocked how crappy it sounded compared to my high shelf only version of this EQ :shock:

No JOKE! WAY more transparent & just sweet... all the bands from 2.5k to 40k. I REALLY like the 2.5k, 5k & 10k on vocals so far. This was very rewarding for all the hard work.

I'm trying to regroup here & get all the files in order so hang in there.

I think some better quality caps in the signal path & larger PS filtering may improove it even more.

STILL NEED advise on the BEST filter cap TYPEs to choose :!:

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 25, 2007, 05:40:00 PM
Quote from: "Purusha"
Quote from: "bellyflop"
Quote from: "khstudio"
500k reverse Audio Taper Pots
Please help if you have a source with a decent price :!:
What are you looking to spend?  Small Bear has them (http://www.smallbearelec.com/Detail.bok?no=116).



Hey, is this the same thing?

http://www.banzaieffects.com/Alpha-16mm-FS-500k-REV-log-pr-17321.html


YES :thumb:

That's KILLER... you guys also have a good (cheap) source.

K
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on January 25, 2007, 05:44:17 PM
Great!

Have you estimated the cost per channel for the full version? OK, without the case...
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: BR on January 25, 2007, 06:05:46 PM
Hi Kevin,
any way you could send me the schem with the AIR section only.   And the pcb design file??
gilparente AT yahoo DOT com.
thanks
Gil
Title: air eq
Post by: Harpo on January 25, 2007, 07:14:02 PM
Quote from: "khstudio"

I was hoping the resistor had something to do with the Linear supply.
Could you recommend a Value & Voltage for this? I'm not sure how important this would be to add or not?  :oops:


The reason for this resistor is to set the min load for the switching supply.
On page 1 you linked to the answer :wink:

Quote from: "khstudio"

Here is the (pre-made) power supply they use:
(I will be upgrading to a Linear PS)
http://www.ipdpower.com/catalog/product.asp?id=378  


This supply is most probably SRW-45-2007, +18V/1,5A on output 1 and -18V/1A on output 2. Scrolling down the Application note mentioned a min load of 10% on output 1. (18V/150 ohm=120mA + load of the eq-circuit to archieve this min load of 150mA).

For your non switching power supply with regulators 7818/7918 or lm317/lm337 you don't need this resistor. It will only pull power and heat up your room. Just leave it out.

Your load caps 1000uF/35V will be fine. Rule of thumb was 1000uF per 1A load. This 5 OPamps will hardly draw that much current, so you're on the safe side.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 25, 2007, 07:37:08 PM
It's post like that, with complete answers, that help me really learn.
I'm starting to feel a piece of mind about this project now with most questions answered (except for the Filter Cap types):wink: & the test board complete, tested & sounding great as is.

Now that that resistor isn't needed the board can be cut down in size :green:

What needs to happen (for this cut down version at least) is for one of us to find a way to make the PCB drawing available outside of the software I created it in... but how :?: Some of you guy are on Macs & I'm not sure the software will work on them?

My session just got canceled so I'm going to refine all the files & parts list tonite.

O... anybody know what brand caps (BOX Type) are white with AV printed on the side???

Still would like to know CAP TYPES???  I'm ordering parts very soon & need to figure this out ??????:green:

Thanks, everybody
Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MrZpliff on January 26, 2007, 02:18:01 AM
Quote from: "khstudio"


O... anybody know what brand caps (BOX Type) are white with AV printed on the side???

Still would like to know CAP TYPES???  I'm ordering parts very soon & need to figure this out ??????:green:

Thanks, everybody
Kevin


I don't know what brand those caps can be  :?  but I'm pretty shure you'd be fine with a polyestercap like WIMA MKS2 1UF +/-10% 63V.

Polypropylene caps are said to have better highs and used in hi-fi stuff...
so for this application they might be the best. They're usually more expensive than polyester...

More on this in the Meta - forum

Check this out:
http://www.groupdiy.com/index.php?topic=2287

http://www.groupdiy.com/index.php?topic=7239

Just my 2 cent....
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on January 26, 2007, 02:36:20 AM
I think the sound of the circuit will dominate the sound of the individual components. The types of caps might make a difference, but I think that it will be minimal in comparison to the circuit topology.

The caps on the board look like bulk polys to me (could be polyprop, polyester/mylar or polycarb) but given the subtle nature of the cct, start with a Wima polyester, they are good caps.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: mick on January 26, 2007, 04:51:58 AM
Hi Kevin I too would like to say a big thank you for all the work your putting into this project, and sorry that I'm of no help to you at this stage, can I just ask which brand of IC's you went with in the end.

Mick
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on January 26, 2007, 05:35:35 AM
Or Polystyrene (Styroflex). [email protected] uses them for the hi-boost in their Pultecs.
I also put them in my Pultecs and they do sound more silky than the WIMAs.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 26, 2007, 05:50:50 AM
Quote from: "Purusha"
Or Polystyrene (Styroflex). [email protected] uses them for the hi-boost in their Pultecs.
I also put them in my Pultecs and they do sound more silky than the WIMAs.


WIMA can come in different flavors so...?
 - But that is interesting... Styrene for the higher bands  :idea:
They would be .47 (20k) & .22 (40k)

I'm GUESSING the originals are just Metalized Polyester... so I guess I'll find those in the WIMA's for my clones.

I'm getting some files ready for you right now :wink:

If it wasn't 10 damn degrees outside I'd be in the shop building :mad:

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 26, 2007, 05:53:29 AM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 26, 2007, 05:56:51 AM
Quote from: "peterc"
I think the sound of the circuit will dominate the sound of the individual components. The types of caps might make a difference, but I think that it will be minimal in comparison to the circuit topology.

The caps on the board look like bulk polys to me (could be polyprop, polyester/mylar or polycarb) but given the subtle nature of the cct, start with a Wima polyester, they are good caps.

Peter


Actually the 1uf in mine are Panasonic "Stacked Metal Film"... not sure the film type http://dkc3.digikey.com/PDF/T071/P1377.pdf

I just had these in stock, they're surprisingly small :wink:

The new board is MUCH smaller 3.5 x 4.5. I was able to knock off an inch or so.

Kevin
Title: air eq
Post by: Harpo on January 26, 2007, 06:06:17 AM
Quote from: "Purusha"
Or Polystyrene (Styroflex). [email protected] uses them for the hi-boost in their Pultecs.
I also put them in my Pultecs and they do sound more silky than the WIMAs.

Nothing wrong with styroflex, but pultecs are another circuit. Styroflex most often are in the pF range. For the 2.5kHz airband you need 4uF in this design. The largest styroflex I could find was 6.8nF, so you would need 588 caps in parallel to get 4uF. Lots of space and bucks for just 1 band (with all 5 airbands you have a total of 7.7uF).
I'd try the WIMA's (MKS-4-100) as peter_c suggested in a previous post. Maybe all a matter of taste, size and $.

Harpo
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on January 26, 2007, 06:15:33 AM
Yes, good point Harpo.

Kevin, I am always re-drawing the layouts for home etching in Corel Draw.
Can you export your PCB layout in such a way one can see also the element
placement and their ID? I don't need the software layout. A simple PDF would be better for me.
Title: Re: air eq
Post by: khstudio on January 26, 2007, 07:58:33 AM
Quote from: "Harpo"
Quote from: "Purusha"
Or Polystyrene (Styroflex). [email protected] uses them for the hi-boost in their Pultecs.
I also put them in my Pultecs and they do sound more silky than the WIMAs.

Nothing wrong with styroflex, but pultecs are another circuit. Styroflex most often are in the pF range. For the 2.5kHz airband you need 4uF in this design. The largest styroflex I could find was 6.8nF, so you would need 588 caps in parallel to get 4uF. Lots of space and bucks for just 1 band (with all 5 airbands you have a total of 7.7uF).
I'd try the WIMA's (MKS-4-100) as peter_c suggested in a previous post. Maybe all a matter of taste, size and $.

Harpo


Yea... forget the Styrene :thumb:

OK, I worked all night to get these files ready in a package for you guys.

I have compiled a master list of emails of all of you interested to send files to.

PM me to be added

ENJOY :green:

Kevin
Title: Re: air eq
Post by: clintrubber on January 26, 2007, 08:13:21 AM
Quote from: "khstudio"

ENJOY :green:

Kevin

 :thumb:

BTW, these 'staggered' shelves remind me of the 'transparency'-mod for the SWR SM-400 bass amp. You got the normal bass & treble & four semi-param mid-bands. You could then add a 'second' treble-control set for another corner frequency. The topology used there (common topology, so also 'API-EQ alike') made it very easy to add bands: the transparency-mod was just another pot, one knob, one hole, one R, one C, some wire.
FWIW...
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on January 26, 2007, 08:25:11 AM
Got the files.  :grin:

Thanks again Kevin for doing this.  :thumb:  :thumb:  :thumb:

My home studio gets better day by day with all this nice DIY projects.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 26, 2007, 08:46:22 AM
DON'T USE THE PCB FILE I SENT OUT!

I WILL RESEND IT>

I made changes that won't match the other files.

Hang on

kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: mikka on January 26, 2007, 09:13:50 AM
Just wanna say a big "Thank You" for your efforts.  I'm impressed ....
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: W DeMarco on January 26, 2007, 09:29:35 AM
My luck with making PCB's has been tragic,  I'm hoping someone might be able to make a couple extra that I am so willing to pay for.  I absolutley fell in love with this EQ from the first turn of the airband.  If interested please PM me, I have PAYPAL!!!!
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: gar381 on January 26, 2007, 10:45:14 AM
If someone is making PCBs for this project
I could use 2 channels worth as well.  Please
let me know.

thanks

GARY
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: jho-audio on January 26, 2007, 10:49:20 AM
me too..  thanks, jason
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: cannikin on January 26, 2007, 10:57:53 AM
same here -- PCBs  :wink:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 26, 2007, 04:53:34 PM
Here's the deal on PCB's:

Peter is supposed to be working on the FULL version PCB but I don't know the time frame or statis... he will have to chime in. His plans were to have PCB mounted components (pots & switch)


x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: BR on January 26, 2007, 05:06:27 PM
Hi Kevin,

I really like and appreciate your idea and efforts.  I'm going to check with Fabio and see if he would be willing to do these.  He's been extremelly busy, so I can't promisse.   But in the mean while, have you checked www.4pcb.com ?  They have a $500 off your first order.  and aftet that you can still use other discounts towards you next few.   I had some neve boards made with them and I ended up with 10 boards free.  Also, your second order doesn't have the tooling charge.   It's worth a shot.

I personally would like an "AIR" only version.  No shelves, or anything else.  I'm still a little confused with this eq,  I'm not sure if the shelving selector is actually part of the AIR circuitry or not.  Could you clarify?

thanks
Gil
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 26, 2007, 05:15:01 PM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: cannikin on January 26, 2007, 05:26:11 PM
This is really cool... haven't been excited about DIY for a Couple months -- thanks for reigniting the flame....

The "Air" Version is all I want to make -- hopefully someone will PCB the thing..

Cheers
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: BR on January 26, 2007, 06:08:37 PM
Hi Kevin,

I would keep all the power supply stuff out of the board.  It would shrink the size and let people use their own supplies.  

So If I understand correctly, you select the frequency you want the AIR to work on, right??  uhmmmm interesting

Gil
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 26, 2007, 06:50:48 PM
Quote from: BR
Hi Kevin,

I would keep all the power supply stuff out of the board.  It would shrink the size and let people use their own supplies.  

So If I understand correctly, you select the frequency you want the AIR to work on, right??  uhmmmm interesting

Gil

The "ADDITIONAL" filtering is part of the ORIGINAL design & MAY be needed for LOCAL stability on EACH board! Remember, this EQ gets up there in frequency.

#2 It's a selectable high shelf with a volume control... AIR is the 40k, but all the setting have a nice usable flavor & really blew the sh*t out of my mixing boards EQ when comparing... I was shocked.

I WILL NOT be straying too far from the original (known to work) circuit unless A- it's an added feature or B- it's an un-needed component that will not effect the already proven performance.

Although, you guys can do what you want.

The only thing I added to the original was a switch on the front to choose Balanced or un-balance operation... taking the top off was NOT an option... even a switch on the back would be better. The jumpers are needed because they change the circuit... I do not think it's possible to just ground or lift pin 3, etc...
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 27, 2007, 11:10:02 AM
Progress is being made :green:

Just wanted to thank Harpo :thumb:

He has been extremly helpful with this project & has made some VERY important recommendations which will be implemented into the schematic & PCB's... Some are un-needed component changes or value adjustments & some are additional PADs - added for user options.

I'm currently working on a direct comparison with the original & also trying to determin wether the 2.5k band can be added or not... if not, that stage will be used for the PEAK detection circuit.

Note: the PEAK circuit may also be added either way.

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 28, 2007, 07:32:44 AM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 29, 2007, 06:32:30 AM
Quote from: "gyraf"
Quote
There's also 2 (regular looking) green resistors with (Brown, Black, Brown - GOLD)... 3 bands & Green... never seen that, any idea's Question


Inductors for RF-protection. 100uH?

Jakob E.


I need help with this one :oops:

I've never had to order inductors before & don't know which ones to get???

Are these OK :?:

http://www.digikey.com/scripts/DkSearch/dksus.dll?Detail?Ref=205455&Row=586083&Site=US
M7837-ND    78F101J    CHOKE CONFORMAL COATED 100UH    
100µH    ±5%    78F    Axial    Bulk    Epoxy
JW Miller A Bourns Company    

http://www.digikey.com/scripts/DkSearch/dksus.dll?Filter

Thanks,
Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 29, 2007, 06:50:54 AM
It's neat that these inductors were added but if you'd ask me I'd skip them for now if they're delaying progress. They're not essential for the functioning.
You would want to add holes for them on the PCB of course (if not already there) so that they can be added later eventually.

Cheers,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 29, 2007, 07:03:32 AM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 29, 2007, 07:18:05 AM
Quote from: "khstudio"
but I don't really totally understand why they were there or do I have the test equipment to see if there needed or not... maybe for keeping the 20k & 40k clean??? :oops:


Hi Kevin,

It's about L1 & L2 at the output, correct ? (as in the schematic on page 1)

Jensen sells a ready-to-go version and calls it a load isolator:
http://www.jensentransformers.com/datashts/oli3.pdf

Quote
OUTPUT LOAD ISOLATOR
DECOUPLES CAPACITIVE LOADS AT HIGH FREQUENCIES
* Prevents oscillation and instability in line driving op-amps
* Maintains much lower output impedance than "build-out" resistors
* Non-ferrous core inductor eliminates added distortion
* No effect on audio frequency response or transient performance
* Less than 0.01 dB insertion loss in a 600 Ohm line

The load isolator is designed to isolate op-amp outputs from capacitive loads such as a long cables. Its series impedance is about 0.3 Ohm across the audio spectrum, but increases to about 40 Ohms at RF frequencies to prevent amplifier instability or oscillation while preserving a low audio output impedance.


Without coils added I'd still keep the same values for R29 & R32.

Cheers,

  Peter
Title: 3d AIR EQ
Post by: Harpo on January 29, 2007, 07:24:45 AM
Quote from: "khstudio"
... I HATE ordering parts... I think it's the worst part of DIY :mad: Kevin


Worst part is paying for parts you orderd wrong that wont be of any use the next decades   :green:

I think, maybe wrong, the inductors should reduce rf from the switching supply that is built in the original unit. Leave them out, but place pads as in clintrubber's previous post.
Title: Re: 3d AIR EQ
Post by: khstudio on January 29, 2007, 07:35:02 AM
Quote from: "Harpo"
Quote from: "khstudio"
... I HATE ordering parts... I think it's the worst part of DIY :mad: Kevin


Worst part is paying for parts you orderd wrong that wont be of any use the next decades   :green:

I think, maybe wrong, the inductors should reduce rf from the switching supply that is built in the original unit. Leave them out, but place pads as in clintrubber's previous post.


DAMN... one more thing that has to do with that F*#kin switching Supply that is not needed. Why would people even use them if they need so much compensation... I DO NOT GET IT! It surely can't be a COST saving issue by the looks of it.

But if this is the case... it's more good news along with the 470uf's being too large... it makes for more room & cheaper parts/values :thumb:

kevin
Title: Re: 3d AIR EQ
Post by: Harpo on January 29, 2007, 08:29:02 AM
Quote from: "khstudio"
DAMN... one more thing that has to do with that F*#kin switching Supply that is not needed. Why would people even use them if they need so much compensation... I DO NOT GET IT! It surely can't be a COST saving issue by the looks of it.

But if this is the case... it's more good news along with the 470uf's being too large... it makes for more room & cheaper parts/values :thumb:
kevin


Think it's a cost issue. They've been small manufacturers selling products that have to meet CE/TÜV/CAN-CSA... much less hassle and cost with prebuilt modules that have this confirmed. Not an issue with DIYers for home use (meeting this specs for shure is obligatory), but that malkjos :twisted: -style cloners may get into severe trouble someday.

Both have their pro's and con's.
a transformer is specced for a constant source voltage (115/230V) which in not a constant in real world. It will introduce more or less hum at 50/60Hz that unfortunately is within the audio band. A switching supply at the same load will be smaller in size and may produce less heat but introduce rail noise in it's switching band.

   INPUT SPECIFICATIONS  
Source Voltage 85-264 Voltage AC
Frequency Range 47-63 Hz
Source Current  
True RMS 1A At 85V Inputut
Peak Inrush 40A
Efficiency .68 -.72 (Varies by model)
    ENVIRONMENTAL SPECIFICATIONS  
Ambient Operating Temperature Range 0oC to +70oC Derating: See Power Rating Chart
Ambient Storage Temperature Range -40oC to +85oC
Temperature Coefficient Outputs 1-4: 0.02%/oC
Conducted Emissions EN 55022 Class B

   SAFETY SPECIFICATIONS  
    GENERAL SPECIFICATIONS  
 
General   Protection Class: I
 
Overvoltage Category: II
 
Pollution Degree: 2
 
 Underwriters
Laboratories
File E137708 UL 60950, Third Edition  
 UL Recognition Mark for Canada
File E137708 CAN/CSA-C22.2 No. 60950:00  
 TUV EN 60950:2000  
   Low Voltage Directive  
 Dielectric Strength  
Reinforced Insulation 4242 VDC, Primary to Secondary, 1 Sec.
Basic Insulation 2121 VDC, Primary to Ground, 1 Sec.
Operational Insulation 500 VDC, Secondary to Ground, 1 Sec.
Mean Time Between Failures 150,000 Hours min., MIL-HDBK-217F, 25oC, GB
Weight 1.00 Lbs.  Chassis and Cover
0.50 Lbs.  Open Frame
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MrZpliff on January 29, 2007, 08:47:17 AM
Quote from: "khstudio"


BTW, The FULL PCB is looking good :wink:  Peter sent me a draft last night :green:

Still working out a few details but I think it's safe to say it's on the way.

I'm ordering parts for about 6 projects including this one... I HATE ordering parts... I think it's the worst part of DIY :mad:

Kevin


I'm in for 2 full PCB:s when they're ready. I ahven't got the time right now to build it anyway... even if I'm thinking of building the "air-section" on perfboard.. I've never bothered to get that etching stuff. I'm too lazy I guess  :oops:

I agree about ordering parts... when building the La-2a I had to order from about half of the western world. Wich when you think of it is a really great thing for us DIY'ers. Without the net I guess much of these projects wouldn't be possible  :grin:  at least not for me.
Title: Re: 3d AIR EQ
Post by: clintrubber on January 29, 2007, 09:44:51 AM
Quote from: "khstudio"
DAMN... one more thing that has to do with that F*#kin switching Supply that is not needed.

I'm not sure which inductors are under discussion here, but if it's indeed those at the audio-output (L1,2 in the schematic on page 1) then it's not related to the kind of supply but because of the reasons I quoted from the Jensen-datasheet of the load isolator.


Quote
Why would people even use them if they need so much compensation... I DO NOT GET IT! It surely can't be a COST saving issue by the looks of it.

W.r.t. switching-supplies:   a TX for 50 or 60 Hz is big, bulky & expensive.

A switch mode power supply works at much higher frequencies and avoids having to use that big iron. It uses a smaller TX of different core-material.  
Despite using more parts & being more complex it's still cheaper. And as said by Harpo, those switching modules are made in massive quantities for tons of applications so can be even more cheaper.

Bye,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 29, 2007, 09:52:58 AM
Quote from: "khstudio"
I'm ordering parts for about 6 projects including this one... I HATE ordering parts... I think it's the worst part of DIY :mad:

I'm not impressed :wink:
I mean, it's easy to mention a few more parts of DIY that are worse than this:

#1. doing the metalwork

#2. having to STOP ordering parts ('cos time for sleep, social stuff, work etc)

#3. having to quit DIY for a while to use the gear you made (to justify making this stuff altogether)  :thumb:


Cheers,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 29, 2007, 10:03:11 AM
Good Points :green:

But I'd rather do the Metalwork any day... I sit behind a computer enough.

+ about 5 KEY pieces I needed are not in stock :mad:

I can't believe a 5k audio taper pot will be out of stock for a month, Damn Mouser. I was also missing 2 items & had 1 bag labled correctly with the wrong sh*t in it. I like Mouser but come on. This scares me when it comes to resistors.

OK, Back on track  :wink:

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 29, 2007, 10:16:31 AM
Quote from: "khstudio"
But I'd rather do the Metalwork any day... I sit behind a computer enough.

I see your point, it's sometimes refreshing to drill & file for excercising some other muscles.

Quote
I was also missing 2 items & had 1 bag labled correctly with the wrong sh*t in it. I like Mouser but come on. This scares me when it comes to resistors.

Hmm, that's bad! So far I've only used a few www-part-sources but so far they've always been spot on except for one mislabeled bag. RS has been perfect so far.

When going to town here for a bag of parts I could always be sure at least something was wrong, so www-ordering was quite an improvement.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 29, 2007, 10:28:39 AM
*I need advise* -

I'm ordering parts & decided to go with Metalized Poly BOX caps & would like to get the WIMA's but damn they're expensive...
Are they REALLY that good at about $1.00 each (1uf) as opposed to about .50cents each for other brands? I guess for the 20k & 40k settings I could go for it but I'm not even sure that they're as noticeable because of they're function in the circuit (just coupling to GND)???    Help me out here if you can.
The Panasonic stacked metal films aren't bad - at about $3.50 for 10 (they are what I had laying around & used)

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 29, 2007, 10:31:27 AM
BTW, I'm concerned about cost a LITTLE because I'm building about 6-8 channels of the Shelves only version & the 1uf's at $1.00 each adds up :shock:

kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 29, 2007, 10:51:29 AM
Quote from: "khstudio"
BTW, I'm concerned about cost a LITTLE because I'm building about 6-8 channels of the Shelves only version & the 1uf's at $1.00 each adds up :shock:

kevin

I think to have seen there are max. four of those 1uF caps in use at a time for one air-band. So for the cost/hassle of some more switching-complexity it could be arranged that you only need 4 i.s.o. 7 of the 1uF caps. I'm not sure it'll be cheaper & as enjoyable in the end, maybe just keep it like it's now.
So what I mean here is that you switch in such a fashion that once you need to go from say 2 to 4 caps of the 1uF-value you don't jump to four 'new' ones but keep two and add another two.

Or try to make other ways of realizing those values. 4uF = 3.9uF + 100nF (but 3.9 might be hard to get). OK, 4uF is also close enough to 3.3uF + 680nF + 22nF.  But hey, if there's some saving at all it'll just be a few $$ per band, hardly worth the hassle I'd say.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on January 29, 2007, 10:56:19 AM
Quote from: "khstudio"
BTW, I'm concerned about cost a LITTLE because I'm building about 6-8 channels of the Shelves only version & the 1uf's at $1.00 each adds up :shock: kevin


have a look at www.Reichelt.de
http://www.reichelt.de/[email protected];ACTION=3;LA=2;GROUP=B326;GROUPID=3155;ARTICLE=12376;START=0;SORT=artnr;OFFSET=16
MKS-4-100 1,0µ - 0.28 EUR a piece

100Vdc/63Vac is enough, you don't need the 250, 400, 630 or 1000V rated caps.

Don't know about the panasonics, but if the sound is ok, stick with them.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 29, 2007, 11:00:06 AM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on January 29, 2007, 11:19:55 AM
For some real costsavings it might be good to reconsider the R & C dimensioning. I mean, using as high as 220 nF & as low as 20 Ohms for a 40kHz filter-frequency (36.2kHz) looks quite wasteful w.r.t. capacitor-costs.
Even more so for the 2.5 kHz frequency: 4uF & 20 Ohms (1/(2*pi*RC) = 2kHz)

I can imagine though you wouldn't want to go that route since it might 'lose/change the magic'; but from a technical point of view this is the obvious way to go when looking for reducing component-costs.

I might be overlooking things, but as long as noise isn't a problem the 200 & 20 Ohms could be increased in value & the caps lowered (=cheaper) by the same factor.
But as said, maybe they're like this for noise-reasons, too lazy now to check if that could be the reason.

Bye,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 29, 2007, 11:32:33 AM
You are exactly correct... I DO NOT want to reinvent the wheel... it's already turning. I have also read about using several smaller caps in parallel instead of one BIG one for many reasons... one I THINK is the speed or responce to higher frequency's but don't quote me on that.

Who know's, it could be fine & everyone is welcome to build how they want but I will stick to how it was for my builds as much as I can... even if just for piece of mind :wink:

BTW, those caps are not available at Mouser or Digikey :mad:

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 29, 2007, 12:00:20 PM
While on the subject of caps (SORRY)

Harpo mention something about Elna's but I have no experience with them :?:

I usually go with Nichicon PW's in the signal path & can hear the diference between them & Pan FC's (Brighter & not as smooth)

Wondering about going with the Elna's for a change. Opinions welcome... please don't give me the CAp Lecture :wink:

There are only a few 470uf's in the S path.

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: cannikin on January 29, 2007, 12:09:25 PM
Hey Kevin,

Here is another resource for you in regards to Elnas ... They are in PA so you will get things in about a day

https://www.hndme.com/productcart/pc/viewCategories.asp?idCategory=72

I plan on using Elna and Nichicon Wimas (just for the hell of it), Won't happen in the immediate future but sometime this spring.

About the PCB layout PDF -- Version 2 is the latest for just the AIR EQ (Correct?).  Is the View of the PCB traces needs to be changed to mirror to etch the PCB?

thanks
David
Title: Re: 3d AIR EQ
Post by: Harpo on January 29, 2007, 12:18:25 PM
Quote from: "clintrubber"
I'm not sure which inductors are under discussion here, but if it's indeed those at the audio-output (L1,2 in the schematic on page 1) then it's not related to the kind of supply but because of the reasons I quoted from the Jensen-datasheet of the load isolator.


Good point Peter and thanks for the link :thumb: , but these JT-OLI-3 are specced 39R||3uH as equivalent circuit, giving increasing impedance above 200kHz and according Kevin's post the 3d-EQ has fitted 47.5R||100uH, a 33times off to not affect the audible band, so there might be another reason going on.

Bye,

 Harpo
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 29, 2007, 12:20:55 PM
Quote from: "cannikin"
Hey Kevin,

Here is another resource for you in regards to Elnas ... They are in PA so you will get things in about a day

https://www.hndme.com/productcart/pc/viewCategories.asp?idCategory=72

I plan on using Elna and Nichicon Wimas (just for the hell of it), Won't happen in the immediate future but sometime this spring.

About the PCB layout PDF -- Version 2 is the latest for just the AIR EQ (Correct?).  Is the View of the PCB traces needs to be changed to mirror to etch the PCB?

thanks
David


Very cool :thumb:
But know creates more choices... decisions decisions. All those flavors they metioned sound good... damnit. I wonder what the "General" choice is on these?

I used vers 2 for my prototype & it works great but I WILL be making a few adjustments before etching again... what, I think the one with the BIG 150 ohm resistor removed is the V2 I resent out & has already been adjusted (spacings) so I think you fine.

I will post any updates here.

It's really not a hard project (at least not now :green:)
I think you'll be surprised at how useful it can be.

Kevin
Title: Re: 3d AIR EQ
Post by: khstudio on January 29, 2007, 12:26:26 PM
Quote from: "Harpo"
Quote from: "clintrubber"
I'm not sure which inductors are under discussion here, but if it's indeed those at the audio-output (L1,2 in the schematic on page 1) then it's not related to the kind of supply but because of the reasons I quoted from the Jensen-datasheet of the load isolator.


Good point Peter and thanks for the link :thumb: , but these JT-OLI-3 are specced 39R||3uH as equivalent circuit, giving increasing impedance above 200kHz and according Kevin's post the 3d-EQ has fitted 47.5R||100uH, a 33times off to not affect the audible band, so there might be another reason going on.

Bye,

 Harpo


Well hopfully the link I posted for the inductor at Digikey is OK because I'll be ordering them so I have them... what can it hurt to put them in?

K
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on January 29, 2007, 12:36:48 PM
Quote from: "khstudio"
While on the subject of caps (SORRY)

Harpo mention something about Elna's but I have no experience with them :?:

Don't know Elna's  :?:  eighter, but like the WIMA's for their sound an look, but don't expect to many audible colour differences between brands in this frequency range. You may have another opinion on this subject.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 29, 2007, 12:44:53 PM
Quote from: "Harpo"
Quote from: "khstudio"
While on the subject of caps (SORRY)

Harpo mention something about Elna's but I have no experience with them :?:

Don't know Elna's  :?:  eighter, but like the WIMA's for their sound an look, but don't expect to many audible colour differences between brands in this frequency range. You may have another opinion on this subject.


Fair enough... I must have mis-understood or confussed another email.

So your saying the WIMA's are good but maybe not as important... maybe because of the job they're performing isn't as critical :? ???

Thanks again for hanging in there thru all my questions  :thumb:

kevin
Title: 3d air caps
Post by: Harpo on January 29, 2007, 01:43:18 PM
My opinion on this may be off, but I think, you recognize to tolerances of the caps and not their brand. These elcos and polys are for usual specced 20%, so for your calculated 2kHz filter a 4uF cap which is 20% above it's labeling and with a resistor 20R f=1/(2*pi()*R*C) set your -3dB point to 1.9kHz. Exchanging this cap with another wich is 20% below it's labeling will set your filter to 2.1kHz, meaning until you don't measure the real value of caps, you cannot compare brands.
Title: Re: 3d air caps
Post by: clintrubber on January 29, 2007, 02:36:03 PM
Quote from: "Harpo"
My opinion on this may be off, but I think, you recognize to tolerances of the caps and not their brand. These elcos and polys are for usual specced 20%, so for your calculated 2kHz filter a 4uF cap which is 20% above it's labeling and with a resistor 20R f=1/(2*pi()*R*C) set your -3dB point to 1.9kHz. Exchanging this cap with another wich is 20% below it's labeling will set your filter to 2.1kHz, meaning until you don't measure the real value of caps, you cannot compare brands.

Indeed ! Good reminder !
As most people here found out when measuring caps, you won't find a 20% tol Wima etc being much closer than that to the stamped value. There's definitely 'a hole in the middle', and guess what happened to those... these were obviously stamped 10%... and so on...
It's a cruel world... which is just another way of saying that you get what you pay for.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: enthalpystudios on January 29, 2007, 03:06:42 PM
http://www.mouser.com/search/ProductDetail.aspx?R=MKS2-1.0%2f63%2f5virtualkey50520000virtualkey505-MKS21.0%2f63%2f5

i would get those.  5%, keeps the bands real nice and close.  with full boards available, it's probably what I'd get.  i mean, you just can't beat the price of this stuff.

the power supply, a parmetal case, and a frontpanel are easily 2/3 the cost of a project like this.

why not go the little extra?

i've been learning to not pinch pennies on parts, but instead pinch pennies on time, and pinch pennies on everything else in life ;]

for all the hard work and dedication, we owe it to ourselves not sell ourselves short.

it's such a tiny little detail, that it seems the only real answer to the question is to answer it your self by picking up 10 of each and building two channels.

i have some extra 1uf wimas if you want to try em out, i'll send em to you...  i have 6 leftover from an order...  not having the schematic handy, if thats enough to test out an air or 2.5khz channel, i'll send em your way... just pm me.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on January 29, 2007, 03:27:24 PM
Kevin, I recommend you to buy some extra caps and match them.
This is what I did for my stereo Pultecs and I have a lot of spare
ones now in order to come really close to 1% difference per ch.
Specially if you plan to use the EQ on the stereo buss.

Regarding those files you sent to us, they are just for the high AIR section, yes?

Why is everyone using the same avatar? :shock: Who is this guy anyway?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on January 29, 2007, 03:49:10 PM
Quote from: "Purusha"
Kevin, I recommend you to buy some extra caps and match them.
This is what I did for my stereo Pultecs and I have a lot of spare
ones now in order to come really close to 1% difference per ch.
Specially if you plan to use the EQ on the stereo buss.

Regarding those files you sent to us, they are just for the high AIR section, yes?

Why is everyone using the same avatar? :shock: Who is this guy anyway?

this tread http://www.groupdiy.com/index.php?topic=20560
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 29, 2007, 11:35:34 PM
Quote from: "enthalpystudios"
http://www.mouser.com/search/ProductDetail.aspx?R=MKS2-1.0%2f63%2f5virtualkey50520000virtualkey505-MKS21.0%2f63%2f5

i would get those.  5%, keeps the bands real nice and close.  with full boards available, it's probably what I'd get.  i mean, you just can't beat the price of this stuff.

the power supply, a parmetal case, and a frontpanel are easily 2/3 the cost of a project like this.

why not go the little extra?

i've been learning to not pinch pennies on parts, but instead pinch pennies on time, and pinch pennies on everything else in life ;]

for all the hard work and dedication, we owe it to ourselves not sell ourselves short.

it's such a tiny little detail, that it seems the only real answer to the question is to answer it your self by picking up 10 of each and building two channels.

i have some extra 1uf wimas if you want to try em out, i'll send em to you...  i have 6 leftover from an order...  not having the schematic handy, if thats enough to test out an air or 2.5khz channel, i'll send em your way... just pm me.


They are the ones I was looking at... I REALLy like what this EQ does to the highs from the 2.5k (or 1.?k - like Harpo said it comes out to be) up... so if it gets any better - that's KILLER :green:

Thanks for the offer but you don't have to do that... I'll be ordering a sh*t load anyway if I decide to go that route :thumb: + you'll need some for your EQ.

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 29, 2007, 11:57:16 PM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on January 30, 2007, 04:50:08 AM
I guess I missed this info  :oops:

What about the full version or at least adding the SUB?

Will you make the layout for this section too?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 30, 2007, 10:08:27 AM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 31, 2007, 02:26:20 PM
How much current (VA) do you think these will draw/NEED per channel?

I'm trying to get a parts list together for BOTH the FULL & CUT version.

Thanks,
Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: enthalpystudios on January 31, 2007, 04:04:22 PM
i'm not sure offhand, but for the most part, you can just get the max current draw off of the spec sheets for the opamps in question and add them up.  that should be pretty much it.  some allowance should be given for the current at switch on, as the transformer should be able to cope with providing current to the fullwave bridge and smoothing caps.

i'd say that if you add up the current draw for each opamp in the circuit, based on the specsheet max, and multiply times 2, and then multiply that by the supply voltage (like 15v or whatever it is), you'll have a good min VA rating for the circuit.  You can always have extra VA on your power transformer without causing any harm

of course if its a HUGE ass power transformer, you may get quite a strong field of interference, but transformers like that probably run over 100 a piece and would be outside the diy realm for a project like this.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 31, 2007, 04:26:53 PM
Well I ordered a few 2x15v @ 15VA... hopfully these will be good for my 4 channel CUT version & a Stereo FULL version??

Thanks,
Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on February 04, 2007, 06:51:34 PM
Quote from: "khstudio"
Well I ordered a few 2x15v @ 15VA... hopfully these will be good for my 4 channel CUT version & a Stereo FULL version??

Thanks,
Kevin


Correction... I ordered 2x18v @ 25VA (18V 1.388A )

Has anyone tried building one of these yet :?:
... You will be pleasantly surprised :green:

I got an email from Peter C today & it looks like the FULL Version PCB's will be ready in the near future :thumb:

Also, I build custom guitar amps & pedals for a lot of guys that have studio's & a few of them stopped by last week & I showed them the EQ I made & they gave me money up front for a few racks of the Shelves version... must have done something right.
 - I'm getting some strange (faint) noise I can't really describe... maybe from being outside the case, hopfully it's this or the missing 100uH inductors...could be oscillation but I'm not sure. I'll post back with a better description of the noise or try to post an audio sample... hopfully someone can help me figure it out? :sad:

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on February 05, 2007, 04:50:29 AM
Quote from: "khstudio"
I'm getting some strange (faint) noise I can't really describe... maybe from being outside the case, hopfully it's this or the missing 100uH inductors...could be oscillation but I'm not sure. I'll post back with a better description of the noise or try to post an audio sample... hopfully someone can help me figure it out? :sad:
Kevin

in case it's oscillation, a 22pF ceramic cap at the traceside between pin 5/8 of the NE5534 should help you out. NE5532 is compensated internal.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on February 05, 2007, 11:52:04 AM
Quote from: "Harpo"
Quote from: "khstudio"
I'm getting some strange (faint) noise I can't really describe... maybe from being outside the case, hopfully it's this or the missing 100uH inductors...could be oscillation but I'm not sure. I'll post back with a better description of the noise or try to post an audio sample... hopfully someone can help me figure it out? :sad:
Kevin

in case it's oscillation, a 22pF ceramic cap at the traceside between pin 5/8 of the NE5534 should help you out. NE5532 is compensated internal.


Thanks man  :thumb:

You guys mentioned this before... about the 5534's & some NOT being stable, right?  It's funny because I'm not using a Signetics like the original - I only have JRC5534D around but I did order some TI NE5534AP's to try.

I am tesing it out now & will try the 22pf - easy enough.

I finished my faceplate last night but need to figure the noise out before moving on :mad:

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on February 06, 2007, 11:37:56 AM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: BR on February 06, 2007, 12:02:24 PM
Dude,  that looks great.  I think I really need one of those 4 pack.
What knobs are those?  They look like Elmas.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on February 06, 2007, 12:18:42 PM
Quote from: "BR"
Dude,  that looks great.  I think I really need one of those 4 pack.
What knobs are those?  They look like Elmas.


Yea I'm pretty stoked about this one too. I made 6 different faceplates yestarday for several projects... I feel like a factory.

Knobs are from Radio Shack... I WISH I knew where to get them in bulk because Radio Shack bumps the price

I make my own faceplates in FPD, then mirror the image, print on lable paper (BACK/ WAX Side) , Super 77 glue (spray) the face then CARFULLY lay the cut out pieces on, then rub them on til they stick, peel off, let dry & Clear Coat... DONE :green:

Thanks,
Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: cannikin on February 06, 2007, 12:44:44 PM
Wow Kevin

thats looks fantastic -- can't wait to build it.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on February 08, 2007, 03:23:42 AM
Quote from: cannikin
Wow Kevin

thats looks fantastic -- can't wait to build it.

 :thumb:

For those of you who have emailed me for the files please hang in there :!:

I'm refining a few things on the PCB & Schematic to make things a little more clear & to make this DIY as smooth as possible. The 470uf/25v caps on the board are too large for the Linear Supply & should be lowered to about 47uf/25v... this was brought to my attention by Harpo. Also, the need for the 100uH inductors is unknown at this point but my prototype is working fine without them. I did order them (2 types are available - Epoxy & Ferite based... I DO NOT KNOW IF ONE IS "BETTER" THAN THE OTHER -  :oops: if anyone knows please help out on this one.


 -  for the Lazer printer/77 Glue method. (if you don't know what that is - Please do a search)
 - for sending it out you'll have to mirror the image & adjust a few small items, no biggie.

Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on February 08, 2007, 06:48:49 PM
Hi Kevin, nice design  :thumb:

Do you mind if I do something similar and offer the racks to the guys here?
Would you happen to have a jpg version of your design?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on February 08, 2007, 08:46:26 PM
Quote from: "Purusha"
Hi Kevin, nice design  :thumb:

Do you mind if I do something similar and offer the racks to the guys here?
Would you happen to have a jpg version of your design?


I don't mind at all man. :wink:

But... I would probably wait a little bit to see how things pan out with this project & to see how many people are interested.

I'll need a little time to try & make a pic of it & get it to you... hang in there & I'll see what I can do.

kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on February 09, 2007, 05:01:19 AM
Sure, no hurry  :grin:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: okgb on February 09, 2007, 08:04:12 AM
Looks great Kev !  

thanks for all your effort on that one
 if i was smarter i'd help more

but i am infor a couple of boards if you make them

regards Greg
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: tomcat on February 09, 2007, 10:39:39 AM
This Forum is worse then a dozen slotmachines ;)

Coool project.   :thumb:

Dont know which project to finish first, but the JRC5532D i ordered already  :green:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MrZpliff on March 02, 2007, 05:19:48 PM
Hi there ...
is there any news about the full version pcb:s ?

just wonderin  :cool:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on March 02, 2007, 05:35:16 PM
Quote from: "MrZpliff"
Hi there ...
is there any news about the full version pcb:s ?

just wonderin  :cool:


I haven't heard from Peter for a while about the Full version PCB's :roll:

I just sent him an email... hopfully we'll hear from him soon.

If he decides NOT to make them, it is possible that Fabio might.


Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on March 03, 2007, 05:11:12 AM
Hi all

I've been buried in the studio for the last month doing a drama series

http://www.tvsa.co.za/showinfo.asp?showid=1197

I am in the studio right now preparing for the final approval in a couple of hours, so I hope to get some family & DIY time in this weekend

I have done the layout, will just have to check it & then build a prototype.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MrZpliff on March 03, 2007, 02:22:08 PM
Quote from: "peterc"


I have done the layout, will just have to check it & then build a prototype.

Peter


Sounds great Peter  :guinness:  :thumb:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: indigom on March 03, 2007, 06:18:36 PM
Quote from: "peterc"
Hi all

I've been buried in the studio for the last month doing a drama series

http://www.tvsa.co.za/showinfo.asp?showid=1197

I am in the studio right now preparing for the final approval in a couple of hours, so I hope to get some family & DIY time in this weekend

I have done the layout, will just have to check it & then build a prototype.

Peter


eagerly awaiting the full-board layout.  : )
cheers ~  :guinness:
-Jay
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on March 03, 2007, 08:19:43 PM
GREAT :green:

I didn't think you'd give up after seeing the (almost complete) PCB.


Thanks Peter,

BTW, I have ALL the components to load the FULL version in stock already so if you want or can, send me a board or so :green: & I'll check it out too.
I can do a side by side comparison to the original.
When the boards are ready will I get the Ultra-Mega-Cool Guy Discount ? :razz:

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: indigom on March 03, 2007, 08:28:56 PM
Quote from: "khstudio"
GREAT :green:

I didn't think you'd give up after seeing the (almost complete) PCB.


Thanks Peter,

BTW, I have ALL the components to load the FULL version in stock already so if you want or can, send me a board or so :green: & I'll check it out too.
I can do a side by side comparison to the original.
When the boards are ready will I get the Ultra-Mega-Cool Guy Discount ? :razz:

Kevin


yah i have all the caps in my stock, but even though i have thousands of resistors I don't have most of them on the list (i have 4 of types required!).  hmm..  this is going to require more digging.

did you mouser your resistors?

-Jay
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on March 03, 2007, 10:32:21 PM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: indigom on March 03, 2007, 11:29:07 PM
Quote from: "khstudio"
I'll be honest with you... on my first prototype of the high shelves version I used the "closest" values - Like:

64.9k = 68k
511 ohm  = 510 ohm
5.62k  = 5.6k

Etc...

It worked so good that when I built my 4 ch version of the high shelves I was concerned that it "MAY" not sound as good as the 1st prototype with the "wrong" values :idea:

I am so close to having it done, maybe tonite if I can find time. I will post back the results if it is better or worse or whatever.

The only difference was the volume was "slightly" higher on the proto (Vers 1) because of this but it sounded GREAT so I didn't care.

If you look at the schematic you can see that ALL the "close value" caps make the volume increase as oppossed to the listed values.

Don't be scared :wink: Although... this was with the shelves only... the FULL version may be more sensitive :!:

Kevin


haha ok Kevin.    Yah I want the full version with two channels, with possible changes on the fixed bands for future mods.

Tonight I researched and ordered all of the resisters at mouser that I was missing (most of them).     Found that I had all the pot's but the CCW ones in my stock, but just ordered a few from Small Bear.
Most of the <1uf caps that I'm using are WIMA, ordered cheap from www.futurlec.com.   Trying Nichicon for the other stuff.
I have Metal Poly for 1Uf or WIMA, have to decide which might be best I guess..

For those interested here are the Mouser PN's for some of the resistors (double checking may be required):
660-MF1/4DC47R5F
660-MF1/4DC2000F
71-RN60D64R9F/R
660-MF1/4CC5110F
71-RN55D1270F
660-MF1/4DC1271F
660-MF1/4DC2051F
660-MF1/4DC2052F
660-MF1/4DC8251F
660-MF1/4DC8252F
660-MF1/4DC1541F
271-18.2K-RC
660-MF1/4DC2002F
660-MF1/4DC4991F
660-MF1/4DCT52R5622F100
660-MF1/4DLT52R5621F40
660-MF1/4DC5111F

anyway, very cool.  Good luck with the rest of the build.    I might have to breadboard this instead of paying those high expresspcb rates.  But i'd like to check out the expressPCB CAD file too.

later !

-Jay
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: fucanay on March 04, 2007, 03:48:03 AM
Wow, cool project. I just read all 16 pages of it. I'll probably be in for 2 full versions when they are available. I have too many things to start and finish now anyway.

Matt
Title: PCB software
Post by: barclaycon on March 04, 2007, 12:05:07 PM
Kevin. Can I ask what PCB software you are using for your layouts ?
In fact, as a general question, what is the best software for this kind of stuff?
I take it the final output is a Gerber format document.
Thanks
Title: Re: PCB software
Post by: khstudio on March 04, 2007, 03:22:39 PM
Quote from: "barclaycon"
Kevin. Can I ask what PCB software you are using for your layouts ?
In fact, as a general question, what is the best software for this kind of stuff?
I take it the final output is a Gerber format document.
Thanks


PCB Express FREE software.

It does NOT create Gerbers :mad:
I wish... but for me it works because it's all I have & I'm etching my own. Printing is all I need. It's a shame because all the hard work I've done can not be simply passed on to the board makers... like Peter, he designed a NEW board around the schematic & Original PCB files I made.

Kevin
Title: PCB Software
Post by: barclaycon on March 04, 2007, 04:05:00 PM
Peter.
What PCB software are you using ?
Just looking for a recommendation.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on March 04, 2007, 04:07:53 PM
Update on the PCB. I'll try & get one done this week for a test.

I have used pots with 5mm leg space & the same kind of Alps push switch that Jakob has used on the Calrec EQ boards of his. Connectors are Molex.

The Shelf switch I see as a Lorlin type wired to the PCB with ribbon (or other) cable.

(http://img.photobucket.com/albums/v318/peter_cornell2002/Neq_web.jpg)


Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Sender on March 04, 2007, 07:28:22 PM
Quote from: "peterc"
Update on the PCB. I'll try & get one done this week for a test.

I have used pots with 5mm leg space & the same kind of Alps push switch that Jakob has used on the Calrec EQ boards of his. Connectors are Molex.

The Shelf switch I see as a Lorlin type wired to the PCB with ribbon (or other) cable.

(http://img.photobucket.com/albums/v318/peter_cornell2002/Neq_web.jpg)


Peter


What program are you using for layout?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: mikka on March 04, 2007, 07:36:02 PM
Mmmh.... Yummy like Haagen Daaz ..... :green:  :thumb:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Sender on March 04, 2007, 07:36:53 PM
Quote from: "khstudio"
Quote from: "BR"
Dude,  that looks great.  I think I really need one of those 4 pack.
What knobs are those?  They look like Elmas.


Yea I'm pretty stoked about this one too. I made 6 different faceplates yestarday for several projects... I feel like a factory.

Knobs are from Radio Shack... I WISH I knew where to get them in bulk because Radio Shack bumps the price

I make my own faceplates in FPD, then mirror the image, print on lable paper (BACK/ WAX Side) , Super 77 glue (spray) the face then CARFULLY lay the cut out pieces on, then rub them on til they stick, peel off, let dry & Clear Coat... DONE :green:

Thanks,
Kevin


Can you go into more detail about how you make your face plates. I'm not exactly sure what kinda of paper you print to.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on March 04, 2007, 10:51:05 PM
KILLER :thumb:

Peter... I forgot what size you said the boards were :?

I'm wondering if two will fit side by side with enough room for a power switch? There's about 16 inches of usable (front panel) space in the chassis that most of us buy here in the US from Par-Metal.

Thanks man,
Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on March 04, 2007, 10:58:41 PM
Sender,
I can't explain it too much better than I have already (this post & others)

Also, others & myself have described this SEVERAL times... do a search.

The answer is Lable Paper... peel off the stickers & print on the wax paper upsidedown, spray 77 glue on faceplate, then rub what you printed onto the face then clear coat it after it dries.

It's a DIY faceplate & you'll have to go thru it to come up with your own system but done right can look very good but IS a PATA.

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on March 05, 2007, 01:48:16 AM
I use Traxmaker PCB software, works well & I know it well.

The boards are 185mm x 80mm, 7.3" x 3.1" if my calculator is right... There should be an inch or so for a power switch.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: matta on March 05, 2007, 02:20:54 AM
Quote from: "peterc"


(http://img.photobucket.com/albums/v318/peter_cornell2002/Neq_web.jpg)


Peter


Show off  :green:

Looks great OOM! Looking forward to getting stuck into a couple when you are ready.

Cheers

Matt
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on March 05, 2007, 02:34:33 AM
Quote from: "peterc"
I use Traxmaker PCB software, works well & I know it well.

The boards are 185mm x 80mm, 7.3" x 3.1" if my calculator is right... There should be an inch or so for a power switch.

Peter


COOL.

When you're ready, email me any additions or changes you've made & I will add them to the schematic to keep things organized. Soon I'll have my new website up & will have space deticated to my DIY including this EQ & the schematic.

http://www.khstudio.us

I see the Bal/UB Jumpers :thumb:
I think I see the inductors too? I added them to mine along with extra PADs from pin 5 to 8 on the NE5534 in case I needed to add a cap for oscillation.

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Bauman on March 05, 2007, 11:25:00 AM
SWEET Peter!!!  :thumb:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: enthalpystudios on March 05, 2007, 11:25:28 AM
very  nice layout...  this should be a pretty inexpensive eq to build, would be worth making enough to have as kind of 'utility' eqs i suppose.

so now grayills? only reason i ask is because with pcb mount pots, which are indeed handy, it can be hard to fit a switch in there, and it probably wont be able to fit inline with the pots.

but...  i'm sure that getting the appropriate traces all to that little space over there is a real pita, and i'm grateful for the work you've done peter..  just thought i'd mention my thoughts.

thanks again kev, peter, and everyone who contributed to this.....  looks like a fun project.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Svart on March 05, 2007, 11:30:53 AM
traxmaker!   :thumb:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on March 05, 2007, 02:30:09 PM
Quote
it can be hard to fit a switch in there,


The Lorlin switches are 27mm across & I have allowed 32 mm on the PCB for the switch. My idea is to mount the Lorlin on the front panel.

I did not do a Grayhill layout because of the cost of the switch. I would think that you could use a panel mount Grayhill & get it inline with the pots?

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MrZpliff on March 05, 2007, 03:14:19 PM
Looks great !  :thumb:
Seems like a nice little project.
 
I'm in for two pcb's as a start ....  :guinness:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: enthalpystudios on March 05, 2007, 11:30:43 PM
cool....  i read the whole thread top to bottom, and can't figure out what the pots should be.... based on the parts list, which lists 5k, and the schem, which lists 550kA CCW, and the first post, which lists both, i'm a bit confused.

but, whichever they are, i do indeed get the impression from reading through the thread that they are rev log, and perhaps this would be a good opportunity to get the right ones in pcb mount from omeg, and even a center detent to boot?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on March 06, 2007, 03:11:25 AM
Quote from: "enthalpystudios"
cool....  i read the whole thread top to bottom, and can't figure out what the pots should be.... based on the parts list, which lists 5k, and the schem, which lists 550kA CCW, and the first post, which lists both, i'm a bit confused.

but, whichever they are, i do indeed get the impression from reading through the thread that they are rev log, and perhaps this would be a good opportunity to get the right ones in pcb mount from omeg, and even a center detent to boot?


Center detent would be KILLER... even my original doesn't have them.

500k REVERSE AUDIO

IS CORRECT :!:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on March 06, 2007, 03:13:25 AM
There are a few errors on the parts list & schematic that I will be taking care of. I'm waiting on Peter so I can have the schematic MATCH the PCB.
It took me a LONG time to reverse engineer this thing & the project is picking up steam here, which is very cool & I'm happy to share it with you guys & thankfull for the help from Peter, Harpo & others... so hang in there & you'll have a well documented project with a schematic, Parts list & PCB.

 I started this in November 2006 so it's moving along well. Peter designed the "FULL Version" board around the Original so I'm confident it will be as good if not better than the Original EQ3D.

PLEASE !!!
I ask the same as Gyraf (Jacob)
This is a DIY project meant for this forum & I don't want to be blamed for "Clones" getting sold on EBAY!

Peter is calling it the "Night EQ" (Full Version-All Bands)
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MrZpliff on March 06, 2007, 04:26:22 AM
Quote from: "khstudio"
Quote from: "enthalpystudios"
cool....  i read the whole thread top to bottom, and can't figure out what the pots should be.... based on the parts list, which lists 5k, and the schem, which lists 550kA CCW, and the first post, which lists both, i'm a bit confused.

but, whichever they are, i do indeed get the impression from reading through the thread that they are rev log, and perhaps this would be a good opportunity to get the right ones in pcb mount from omeg, and even a center detent to boot?


Center detent would be KILLER... even my original doesn't have them.

500k REVERSE AUDIO

IS CORRECT :!:


Smallbear has 500K Reverse Audio pots.
www.smallbearelec.com

Maybe we could ask if he could find center detent pots for us.
These pots won't fit the pcb as far as I'm concerned.... when I built the Calrec Eq I just used some short wires for the 100K reverse audio pots.

Edit: Mail sent to Steve at smallbear about center detent pots.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on March 06, 2007, 04:51:08 AM
Quote
Smallbear has 500K Reverse Audio pots.
www.smallbearelec.com


This is what I used... Great price the more you get, I bought 50 pots :razz:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: enthalpystudios on March 07, 2007, 09:42:54 PM
how does this thing sound in bypass?  i read in another post brad avenson mentiones 'not flat,' but is it significant?  

just curious about whether or not i should go with hard bypass or not.  suppose it couldnt hurt, but since you have one kev, just wondering if you've noticed anything.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on March 08, 2007, 01:09:51 AM
Quote from: "enthalpystudios"
how does this thing sound in bypass?  i read in another post brad avenson mentiones 'not flat,' but is it significant?  

just curious about whether or not i should go with hard bypass or not.  suppose it couldnt hurt, but since you have one kev, just wondering if you've noticed anything.


I would consider the BYPASS function of this EQ pretty good but nothing can be better/truer than "True Bypass" IMHO.

It works fine for a quick reference on/off... if you don't like what it's doing, pull it out of the chain - this is what I do & is pretty easy with a patchbay.

I'd like to have True-Bypass on ALL my gear but it's a little extra work dealing with relays & the power supply for them. Some day I'll take the time to do it :oops:

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on March 08, 2007, 01:28:39 AM
Quote
how does this thing sound in bypass? i read in another post brad avenson mentiones 'not flat,' but is it significant?


????

Should be pretty flat, the bypass chain is input buffer to summing amp to output balancing stage. The bandwidth goes up high to accomodate the Variable Shelf, & the input stage is very similar to Jakob's SSL clone.

Not sure what the original sounds like.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MrZpliff on March 09, 2007, 02:27:26 AM
I've just checked with smallbear...
He can get center detent 500k reverse audio pots for us...
only problem is we need to order a 1000 of them...
the price is good though under a dollar a piece....

Delivery in 8-10 weeks...

Feels like someone in the US is better suited to arrange this than me over here though...
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on March 09, 2007, 05:59:15 AM
Maybe one of our UK members can check with Omeg? Their minimum order is usually 25 pieces & their prices are very good.

 I wouldnt mind ordering pots, but then buyers would have to pay for 2 sets of international shipping.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: okgb on March 09, 2007, 09:12:55 AM
There was the other fellow from U.K.  who was stocking quite a few
of the C type reverse , he usually speaks up in the black market
most recently about the 2k2 or a.p.i. values

Go Pete  Go !
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Godders on March 09, 2007, 09:54:15 AM
Quote from: "peterc"
Maybe one of our UK members can check with Omeg? Their minimum order is usually 25 pieces & their prices are very good.

 I wouldnt mind ordering pots, but then buyers would have to pay for 2 sets of international shipping.

Peter
I just emailed them. I've been following this thread with great interest, I'd be glad for even a small opportunity to do something helpful.

I'll let you all know.

Cheers

Nick
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: enthalpystudios on March 09, 2007, 10:26:03 AM
was meaning to ask this, but i was thinking the same thing "slenderchap" at audiomaintenance.  Great prices as well.

but my question is, the standard omeg value would be 470k, and i'm wondering if any modification would need to be done to keep the response flat with pots at center detent.  i do like the idea of using omegs however as they are pc mount....  the board is layed out well, it would be a shame not to use it for its intended purpose, plus I've got a good bit of work done on a frontpanel layout in corel, so i'm def. going to go with pc mounted.

the 470k thing is all i wonder about....   i'll have to try plotting rev log curves and see what the resistance actually is at halfway with a 500k and with a 470k. i'd imagine that making R30 a 100k multiturn trimmer would probably allow the response at center position to be tamed, as all the pots are doing is setting the level of bandpass signals to be summed.  but also, i'd imagine that a rectangular cermet trimpot could have wiper bent up to meet one leg, soldered, and then fit (more or less) into the existing pads for r30.  but this is provided that the pots track pretty well....   trimming the 5.62k summing resistors may be not only too much work for too little return as far as flat response goes, and also may be a bad idea to change the summing bus impedance much.

just thoughts
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on March 09, 2007, 01:05:00 PM
I forget... didn't I mention the ohms @ the halfway point?

If not, I'll recheck. I think I have it written down.

The more I think about the center detent pots (or ANY pot besides the originals), you may be on to something when it comes to the "REAL" value & the center point... I'm sure some components could be adjusted to compensate but I wouldn't want to do it.

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on March 09, 2007, 03:49:53 PM
I remember 40k at the centre point.

Pots are +- 10% tolerance usually so I dont know how much difference it would make. A multiturn pot would be a good idea though.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on March 09, 2007, 04:33:46 PM
OK,
I just set ALL the bands of one channel to the center & got readings between 46k & 48k... 3 out of the 5 were closer to 47k.

So 47k it is @ the mid point.

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on March 12, 2007, 06:42:12 AM
Before I get into anything crazy, what's the best way to test this thing... like for distortion, bad IC's, etc... :?:

Thanks
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on March 12, 2007, 06:46:41 AM
Nice work Kevin. Where did you say you got those red knobs from? I really like them on your front panel design  :thumb:

I think I need to start more colourful designs for my cases  :green:

BTW, those are Mnats PSU boards? That's really great as I have a bunch waiting to be used.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on March 12, 2007, 08:09:11 AM
Hi Kevin,

congrats  :thumb:

easyest way to compare is to plug both units in your patchbay, both set to bypass. (1 ch. nightair/1 ch.3dAir). Feed them with a squarewave signal and scope before and after elcos C1, C14 and C15. This way you also check for faulty Op-amps U4 at pin 1 and 7 and U5 at pin 6, cause these are always in your signal chain. Your described harshness may come from these, if there's something wrong. The filter-caps in the nightair has the cheapest availiable 1uF poly's built in, but in bypass the filter stages are out of circuit.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on March 12, 2007, 03:31:46 PM
Quote from: "Harpo"
Hi Kevin,

congrats  :thumb:

easyest way to compare is to plug both units in your patchbay, both set to bypass. (1 ch. nightair/1 ch.3dAir). Feed them with a squarewave signal and scope before and after elcos C1, C14 and C15. This way you also check for faulty Op-amps U4 at pin 1 and 7 and U5 at pin 6, cause these are always in your signal chain. Your described harshness may come from these, if there's something wrong. The filter-caps in the nightair has the cheapest availiable 1uF poly's built in, but in bypass the filter stages are out of circuit.


OK, I will test later today :thumb:

Your saying the Electro's could be the problem & I can see it on the scope. Believe it or not I just FINALLY got a decent tone generator but have never done a squarewave test. I have an old Tektronix 564b scope.

I'm sure this is something I NEED to do for testing a lot of my gear & problems :oops:

Quote
The filter-caps in the nightair has the cheapest availiable 1uF poly's built in

Really :shock:

We talked about this WAY earlier in the thread but no one knew what "Type or Brand" they are... do you?

The more I listened to the REAL one last nite it DID work - it was just harsh & I felt it had a "Headroom" issue too.

Thanks man
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on March 12, 2007, 03:33:06 PM
Quote from: "Purusha"
Nice work Kevin. Where did you say you got those red knobs from? I really like them on your front panel design  :thumb:

I think I need to start more colourful designs for my cases  :green:

BTW, those are Mnats PSU boards? That's really great as I have a bunch waiting to be used.


Radioshack knobs & MNATs PSU.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Bauman on March 12, 2007, 04:10:01 PM
Great stuff Kevin!!!  :thumb:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on March 12, 2007, 05:46:28 PM
Quick pic of the half done prototype

(http://img.photobucket.com/albums/v318/peter_cornell2002/NEQ1.jpg)

I'll go with lin pots for testing, anyone spoken to Omeg yet?

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on March 12, 2007, 06:10:08 PM
KILLER :thumb:

I'm very happy that all my hard work did not go waisted. I hoped but didn't think it would take off this fast. Thanks to Peter for believing in my drawings of a unit he can't see :razz: AND for all his hard work too.

Quote
I'll go with lin pots for testing,


I think I tried that & it was TOO sensitive... Hooking up audio Tapers BACKWARDS & using them BACKWARDS works pretty good for testing.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: gar381 on March 12, 2007, 06:14:59 PM
WOW...Really nice looking stuff Kevin! :thumb:
I need to put some of  your "AIR"s on my short DIY list.
Maybe after some 553s.  :?

GARY
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Godders on March 13, 2007, 05:22:39 AM
Quote from: "peterc"
.... anyone spoken to Omeg yet?

Peter
They can do 470K Rev Audio with center detent, they didn't offer up any pricing though.

Which type do we want?

http://www.omeg.co.uk/products.htm

Cheers

Nick
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on March 13, 2007, 07:43:29 AM
What about the BR16ECO, that is the 16mm ECO type with a PCB bracket.

They should be about a quid each.

I would be in for 10 of them.

Thanks
Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sonicwarrior on March 13, 2007, 08:43:45 AM
Will someone produce a batch of these PCBs?

If so I would also take the pots for 2 PCBs.
I'm a little confused as the original schematic listed 6 470 k pots but the clones seem to be a bit different. :?

Man, if only Cosmo would be as nice as Omeg. *dreaming*
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Godders on March 13, 2007, 09:16:20 AM
Rev log is the same as Rev audio right?

And there are several options for length of spindle etc. on the enquiry form. If someone wants to take a look and tell me which is the correct one (or whther it matters):

http://www.omeg.co.uk/bre16brc.htm

I'm more than happy to get a group order together but obviously I don't want to buy a load of the wrong pot. :?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sonicwarrior on March 13, 2007, 09:28:46 AM
Quote from: "Godders"
Rev log is the same as Rev audio right?


Yes, it's the same as "Law C":

(http://www.omeg.co.uk/images/1lawcotx.gif)
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Godders on March 13, 2007, 09:33:55 AM
Thanks Joachim. :thumb:

Cheers

Nick
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on March 13, 2007, 03:54:19 PM
Quote from: "sonicwarrior"
Will someone produce a batch of these PCBs?

If so I would also take the pots for 2 PCBs.
I'm a little confused as the original schematic listed 6 470 k pots but the clones seem to be a bit different. :?

Man, if only Cosmo would be as nice as Omeg. *dreaming*


If you follow the thread you'd see that Peter is working on it :wink:

I made the schematic & I don't recall listing 470k for the pots :roll:

They are 500k RA... the original ERROR was 5k but that was WRONG & FIXED. (or addressed)
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sonicwarrior on March 14, 2007, 03:14:26 AM
Quote from: "khstudio"

If you follow the thread you'd see that Peter is working on it :wink:


I'm sorry, here are so many big threads and I don't have the time to read all information and let them stay in my brain. :oops:
That's the main problem with all the big threads here.

If it helps I can post the project information on my sdiy.de site (which still has no root page) or the groupdiy.de site which I haven't used by now.

Quote from: "khstudio"
I made the schematic & I don't recall listing 470k for the pots :roll:

They are 500k RA...


470k or 500k is a big difference. :wink:

But anyway I just took the 470K from Godders posting. :razz:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Godders on March 14, 2007, 05:15:49 AM
OK, I kind of assumed from what Peter had said that 470K would be OK. Apologies for that.

That's no joy from Omeg then for 500K pots.

Cheers

Nick
Title: Corrections
Post by: barclaycon on March 14, 2007, 11:31:46 AM
Hi Kevin,
Had a look on your site for the corrected schematic but couldn't find it.
Title: Re: Corrections
Post by: khstudio on March 14, 2007, 01:08:54 PM
Quote from: "barclaycon"
Hi Kevin,
Had a look on your site for the corrected schematic but couldn't find it.



Quote from: "khstudio"
I'm working on my web site & will have all the info posted there in the near future.
Title: Schematic
Post by: barclaycon on March 14, 2007, 03:36:14 PM
Thanks Kevin.
I will check the thread for updates.

Martyn
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on March 20, 2007, 04:56:15 PM
I bought 6 log pots (500k) & put them onto the PCB. However, all the change is in the last 10% (clockwise) of the travel, so it makes it difficult to evaluate the sound.

I have ordered some rev log pots from Smallbear, once I've put them in I'll update this thread.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on March 20, 2007, 05:07:50 PM
Quote from: "peterc"
I bought 6 log pots (500k) & put them onto the PCB. However, all the change is in the last 10% (clockwise) of the travel, so it makes it difficult to evaluate the sound.

I have ordered some rev log pots from Smallbear, once I've put them in I'll update this thread.

Peter


Yea, I think most of the usable action happens between about 20k & 80-100k.
(except for the "AIR" control... Probably 0 to 40k.

Peter, did you try hooking them up & using them Backwards? I know it's still not right but I think it helps a little.
Using a regular LOG really limits the usable range when hooked up forward.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on March 20, 2007, 05:46:43 PM
Quote
Peter, did you try hooking them up & using them Backwards?


Thanks, I'll try that in the morning.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on March 22, 2007, 08:58:45 PM
Peter... how'd you make out man?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on March 23, 2007, 01:33:54 AM
I am like a bricklayer in Beirut at the moment, I'll try & get to it over the weekend.

Peter
Title: Current Schemo?
Post by: nielsk on April 15, 2007, 10:22:33 AM
I want to proto an air band version while we wait for complete version boards, but I have searched the entire thread and it seems any schematics are no longer accessable. Is there somewhere the current version and a parts list are posted?

Thanks!
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on April 16, 2007, 04:14:15 PM
Hi all

FINALLY!

(http://img.photobucket.com/albums/v318/peter_cornell2002/NightEQ.jpg)

My pots arrived from Smallbear on Friday & I put them onto the PCB & did some listening this weekend. I'm not given to over-blown descriptions, but this is a VERY nice EQ! The frequencies are great, lots of cut & boost & the air-band is very sweet at 20kHz & 40 kHz.

I will try & post some samples, but this is a keeper for me.

Can all those who want to buy PCB's please let me know, I'll post a thread on the Black Market.

http://www.groupdiy.com/index.php?topic=260973&sid=a5b8a8dd5a990b96dfca5a4debd59424#260973

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on April 16, 2007, 04:33:26 PM
I thought you gave up man  :razz:

This is KILLER!  :thumb:

Thank you Peter,
I was really hoping all my hard work could be shared & take off like this.
I would like 4 boards for myself.

So, you liked it?... cool. It's a very nice EQ & not a hard build. Great for the master & sub busses too.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: fucanay on April 17, 2007, 01:22:15 AM
Kevin,

Are you going to make the AIR boards available to purchase? Those are the ones I really want.

Matt
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: fucanay on April 17, 2007, 02:10:34 AM
Thanks Kevin,

I'll get 2 of Peters boards.

Matt
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on April 17, 2007, 02:48:26 AM
I didnt do an overload LED as I didnt have that part of the cct & it is pretty easy to hear the overload in this cct.

Everything is the same as Kevin's last diagram, I have added some extra PSU decoupling but no change to the audio circuit.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on April 17, 2007, 03:12:20 AM
I wasn't sure if you added it or not. No big deal.

I also don't feel it's needed... use your ears.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on April 17, 2007, 04:07:41 AM
Great work !!!

Is there any parts list floating around yet?

Also the measures for between the pots would be great for the front panel layout.

NOTE: I will be doing a batch of cases for the full 3DEQ stereo version ASAP. It will be designed for 1U cases, I guess there should be enough space for this.

HERE (http://www.groupdiy.com/index.php?topic=261120#261120) is the thread if you are interested in the case or two for this project.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: matta on April 17, 2007, 04:22:54 AM
Oom,

Well you lied... you have been doing more than washing dishes!!! Well done! It looks great. Looks like those posts are PCB mount, didn't know they were and option from Small Bear.

Looking forward to making a pair, one can't have  enough EQ's right ;-)

Cheers

Matt
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on April 17, 2007, 04:33:15 AM
Matt

The pots are not PCB pots, I added wires into the holes to make them into "PCB mounted" pots. You know how much I hate flying leads to offboard components....

Omeg pots anyone?

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on April 17, 2007, 05:37:26 AM
Sorry if that has been asked before, but does anyone happen to have scans of the manual ?

Thanks,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: raysolinski on April 17, 2007, 10:37:29 AM
This looks cool!.  Hats off to Kev and Peter...Are they be balanced in/out? One other thing...You can't take a log pot and use it backwards and think it is reverse log...it is about the taper of the pot, not the rotation of change.. Law C (reverse log) is tough to find but the taper is just right for most of our audio aplications. It made a huge difference when I put 50k reverse logs in my 312's (and adjusted the feedback resistor accordingly). Any pot will work but as Peter noted all the change will be at one end if you use linear or audio tapers...that said.

I am in for 2!  :green:

Cheers,
Ray
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on April 17, 2007, 11:20:05 AM
Balanced or unbalanced I/O, set with jumpers.

Smallbear have 500k Rev log pots, not PCB mount though. See 2 posts up for mounting method. Linear & log types did not work very well at all.

I have suggested a group buy from Omeg, their pots are reasonably priced & great quality (plastic conductive) & they can give us a centre detent.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Godders on April 17, 2007, 11:42:52 AM
I already checked with Omeg Peter, 470K only.

Cheers

Nick
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: jensenmann on April 17, 2007, 12:03:28 PM
http://www.musikding.de/product_info.php?cPath=50_100&products_id=554

500k rev log pots, but not PCB mountable. If there´s enough interest I could try to talk this store into adding PCB mountable pots to his goods (I already did that successfully with PKES knobs).

big :sam:  for you guys who made this project possible
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Ptownkid on April 17, 2007, 02:30:01 PM
Whre is the correct BOM for peters boards, i saw the excel one but it's incomplete.

Also, I will most likely be doing an alpha order in the very near future.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: fucanay on April 17, 2007, 02:47:55 PM
Quote from: "Ptownkid"
Whre is the correct BOM for peters boards, i saw the excel one but it's incomplete.

Also, I will most likely be doing an alpha order in the very near future.


When you do, please start a new thread. I'll order 12 of them from you. These seem rather rare.

Matt
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on April 17, 2007, 06:21:06 PM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on April 17, 2007, 06:30:05 PM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on April 18, 2007, 01:47:58 AM
I used Kevins last schematic....... It may sound a bit general, but thats all I have!

I added
4 x22R resistors,
4 x 22uF/25v caps,
12 x .1uF caps (2 per IC) &
2 x 22uF/63v caps for the input.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: fucanay on April 18, 2007, 02:18:47 AM
Peter,

Any chance of an overlay graphic? That along with the schematic and parts list on the front page should lead us in the right direction.

Thanks

Matt
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: audioforge on April 19, 2007, 04:28:56 PM
looking the great pics kevin upload at grouddiy i see 4 ne5532(U1 U2 U3 U4) and 2 ne5534 (U5 U6). on schem and bom 5 ne5532 one ne5534......
did i miss something????
 :?
audioforge
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on April 19, 2007, 04:40:14 PM
The extra 5532 is for the "CLIP LED" which it NOT on Peters PCB.

It's probably the only thing missing.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on April 20, 2007, 01:24:22 AM
Audioforge

I have changed the chips slightly, just allow for easier PCB layout. I only do single sided (making DS PCB's at home is a realPITA) so I did not use the 2nd half of the first 5532. I used a 5532 instead of a 5534 for the output section.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on April 20, 2007, 03:41:46 AM
Quote from: "jensenmann"
http://www.musikding.de/product_info.php?cPath=50_100&products_id=554

500k rev log pots, but not PCB mountable.


Anyone brave enough to go for rotary switches i.s.o. all these rev-log pots ?  :cool:

I'm seriously considering it, since that 'stereo-issue' keeps nagging a bit
(with pots like this it'll be hard to adjust left & right consistently).

Bye,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sneakthief on April 20, 2007, 05:09:37 AM
What about buying twelve alpha 500k rev log pots in addition to six regular dual alpha pots (any value) and sticking the 500k pot pcb's inside of the duals?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on April 20, 2007, 05:46:22 AM
Quote from: "sneakthief"
What about buying twelve alpha 500k rev log pots in addition to six regular dual alpha pots (any value) and sticking the 500k pot pcb's inside of the duals?

I see what you mean, but I'm not sure that would guarantee good enough tracking (dual pots are usually pretty bad in that respect). You could match of course, but that might require quite a few pots to select from.

The switched rotary could also 'solve' the more or less minor issue of the somewhat strange EQ-topology: you need to have these rev-log pots dead center to have flat response for a band. Where is that point ? (could be solved by an additional trimmer, but that's also hassle).

I understood from KHstudio that there was also a mastering-version from this EQ that does use switched rotaries, and for a good reason.

So while at it, let's be at it and use switches  :cool:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sneakthief on April 20, 2007, 05:57:22 AM
Yeah, it'd be important to match the dual pots.

As for rotaries, the question then becomes: how many positions and what values :wink:

Did you have any particular (affordable) rotaries in mind - eg. what about this? http://www.groupdiy.com/index.php?topic=22139&highlight=rotaries
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sonicwarrior on April 20, 2007, 06:01:51 AM
Well, I ordered two stereo units, so I can try one with switches and one with pots. :green:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sneakthief on April 20, 2007, 06:20:18 AM
Or six of these (2x24) for 8 euro each?

(http://www.uraltone.com/kauppa/images/product_images/popup_images/rotarycn.jpg)

http://www.uraltone.com/kauppa/product_info.php?products_id=1077

The only catch is that they supposedly won't fit in a 1u rack.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on April 20, 2007, 06:23:26 AM
Quote from: "sneakthief"
Yeah, it'd be important to match the dual pots.

As for rotaries, the question then becomes: how many positions and what values :wink:

Did you have any particular (affordable) rotaries in mind - eg. what about this? http://www.groupdiy.com/index.php?topic=22139&highlight=rotaries

Not, not a specific type in mind yet - too bad it's a (rev)log-law otherwise not too elaborate tricks with one single-deck rotary and a boost/cut switch could be done.

There are other ways of course, but these will deviate too much from this design.

Regards,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sneakthief on April 20, 2007, 06:31:54 AM
Did you know you can approximate a reverse log pot using a dual-linear pot?

Check out the schematic on the right:
(http://home.comcast.net/~sbernardi/elec/og2/square_law_attenuator.gif)

"Square Law Attenuators

The figure below illustrates another way to approximate logarithmic attenuators using dual linear pots. In the first circuit, we get a nice log/audio taper. It is actually a square law, but it has a nice "feel" to it. The second circuit is an inverse sqaure law attenuator (notice it's the configuration of the first circuit flipped upside down), and is probably the more useful of the two because it approximates the reverse log taper - and reverse log pots are hard to find.

Use similar rules about keeping the load resistance RL 10 times the value of the pot to minimize loading effects.

For the square law attenuator, The equivalent resistance presented by the network (as seen by Vin) varies from Rpot || RL when the pot is at 0% rotation, to Rpot when it is at 100% rotation.
For the inverse square law attenuator, The equivalent resistance presented by the network varies from Rpot || RL when the pot is at 0% rotation, to Rpot / 2 when it is at 100% rotation."

- Courtesy Scott Bernardi: http://home.comcast.net/~sbernardi/elec/og2/partsub_pots.html
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on April 20, 2007, 06:39:24 AM
Quote from: "sneakthief"
Did you know you can approximate a reverse log pot using a dual-linear pot?

Cool info  :thumb:  
Let's now check if it can also do a rev-log rheostat (which is what is needed for the Green & Air-EQ).
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on April 20, 2007, 06:46:05 AM
Quote from: "sneakthief"
Or six of these (2x24) for 8 euro each?

(http://www.uraltone.com/kauppa/images/product_images/popup_images/rotarycn.jpg)

http://www.uraltone.com/kauppa/product_info.php?products_id=1077

The only catch is that they supposedly won't fit in a 1u rack.

Hmm, too bad they don't have single decks... 2channels*6switches*8Uri's = impressive...

But I doubt a switched alternative could be much cheaper than this, unless a 12-pos would be enough (don't think it will).
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on April 20, 2007, 06:59:29 AM
Quote from: "clintrubber"
Quote from: "sneakthief"
Did you know you can approximate a reverse log pot using a dual-linear pot?

Cool info  :thumb:  
Let's now check if it can also do a rev-log rheostat (which is what is needed for the Green & Air-EQ).

Haven't checked it, but I believe there's no real reason why we can't skip the rev-log-pot.
I.s.o. the 500k rheostat (2 terminals) use a single log pot (three) & keep the 5k62 and/or adjust.
Or i.s.o. the single log perhaps a dual-lin configured as shown above. The reason for this might be the possibly/assumed lower tolerances of lin-pots (from sample to sample).

For an alike inverting topology, I recall a parametric EQ (state variable filter) that "should have used" rev-log 'floating variable resistances' (rheostats) as well for the freq. SVF's usually do.
This one didn't, it used log-pots. It works.

I realize this suggested change might still have some flaw somewhere (please debug) and/or might feel like it won't sound any longer like the real thing.
I doubt the latter, but feelings are feelings.

Bye,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on April 20, 2007, 07:13:43 AM
This may be a PAQ (Previously Asked Question), but I don't see how the air-band can be boost only. It sums just like the others. Are the values of R34 & R35 correct ?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: wmb on April 20, 2007, 07:17:14 AM
This looks like a very interesting project. Does anyone have even a rough estimate of the cost of building a couple channels less case, pots and connectors? Also, how many boards can be powered by the power supply board being offered with the main pcb.

I'm (very) slowly putting together a couple 1081's and would like to build something less expensive and with a shorter turn around. After reading all 22+ pages a couple channels or more would be interesting if the boards are less than $100 per channel to stuff.

Cheers, wm
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on April 20, 2007, 08:17:27 AM
Quote from: "clintrubber"
This may be a PAQ (Previously Asked Question), but I don't see how the air-band can be boost only. It sums just like the others. Are the values of R34 & R35 correct ?

Reason for boost only is the labled 2.5kHz shelf band ( for real it is a 1.25kHz shelf, check fo -3dB=1/(2xPI()xRxC), makes even more sense, as the 2.5kHz is also availiable in the air section ).  Assuming this filter section with it's pot centered to +/-0dB you can't lower the amplitude of any frequencies above in the air section as this section is also part of the summing node.
The values of R34 (500k rev log) and R35 (5.62k) are correct, giving you an inverted AV varying from 0.1 to 10 (AV=-1 x R30 / (R34+R35)). Switching on the air band to any selectable frequency will always add an at min. -20dB shelf level on top.
I don't believe the rev.log trick with a dual lin mentioned above will work as a rheostat. you'll have to make it 50k at center, 500k full ccw. Please let me know better.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Dave_B on April 24, 2007, 10:55:20 AM
Peter are you planning on making the PCB artwork available for those who'd like to roll their own boards?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dissonantstring on April 24, 2007, 11:54:48 AM
Hi everyone,
I've contacted Colin (aka slenderchap on the forum from audio maintenance) and he says that he can get Omeg 470K rev. log pots with center detent available for all of us who are about to build the Night EQ (thanks to Kevin H. and Peter C.)  

Colin says that the pots are 10% so they should provide a very close value to the required 500K.  He would like to know if we would prefer 16mm or 20mm sized and also if we prefer PC mounting or solder lug termination.
I want to thank Colin for his help in sourcing this somewhat diffiuclt to find pot with center detent! :thumb:

I'm thinking that since most seem to be thinking of a dual channel in a 1U chassis that a 16mm pot with PC mount would be best, but I'd like to hear what others are thinking.

Kind Regards,
Grant
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on April 24, 2007, 03:02:10 PM
The Lorlin is 27mm in diameter, the P20 Omeg is 15mm from the shoulder on the solder pins to the shaft centre, & the P16 is 12,5 mm from the shoulder to the shaft centre. So either would work.

The board will accomodate the PCB mount omegs, pin spacing is 5mm.

I estimate about $25-00 per channel for components excluding PCB & pots.
That is based on what I paid for my prototype channel in South African Rands converted into USD.

I will make the PCB pattern available for home etching, lets get the PCB's done first.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on April 24, 2007, 03:06:50 PM
Definitely 16mm but with solder lug termination. I am in the process of making the front panel design
for a batch of Night cases and it's just gonna be too much crowded if all pots are soldered to the
185mm wide PCB.

I think that a nice front panel design is more important than the commodity of avoiding soldering a few
extra wires. At the end you will anyway look only at the front panel design and not into what is inside

 :wink:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Greg on April 24, 2007, 03:10:48 PM
I hope this doesn't start some big debate... but if the board acommodates PCB mount OMEGs I'd prefer PCB mount over solder lug.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dissonantstring on April 24, 2007, 03:30:40 PM
o.k. one vote for solder lug termination and confirmation that either 16mm or 20mm pot size fitting the PCB from Peter (thanks Peter!) and one vote for PCB.

obviously solder lugs would accomodate various front panel layouts and we are talking about 6 of those pots plus a rotary switch on the front panel for each channel (not to mention a power switch) for the full version.
so, any more votes for either pcb or solder lug terminations?

Peter, which inductor would work best with your PCBs or will any do?

cheers,
grant
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Greg on April 24, 2007, 03:37:08 PM
Also keep in mind that it's still quite easy to solder to PCB mount pins if someone still wants to run wires to the PCB. It's much harder to go the other way.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dissonantstring on April 24, 2007, 03:57:57 PM
ah, excellent point greg!
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on April 24, 2007, 04:33:57 PM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on April 24, 2007, 04:48:47 PM
Quote
Peter, which inductor would work best with your PCBs or will any do?


I did not use any inductors on the prototype! But I have used inline inductors (they look like resistors) in other projects & they worked well. This is what the board is laid out for.

PCB pins are fine for flying leads, what I do is put a bit of heatshrink over the solder joint to get the extra mechanical strength. "I hate flying leads..."

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on April 24, 2007, 05:16:43 PM
Quote from: "peterc"
Quote
Peter, which inductor would work best with your PCBs or will any do?


I did not use any inductors on the prototype! But I have used inline inductors (they look like resistors) in other projects & they worked well. This is what the board is laid out for.

Peter


I used the inductors on mine as well but I'm still not sure if they're needed or not :?  It was mentioned that they may have been added because of the "Switching Power Supply" (which we will NOT be using)... but I can say they didn't hurt the sound in or out to my ears... may need test equipment to really see what they're doing.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sonicwarrior on April 25, 2007, 02:28:06 AM
Quote from: "Purusha"
I think that a nice front panel design is more important than the commodity of avoiding soldering a few
extra wires.


Well I hate wiring extra wires if there is the possibility to PCB-mount the pots.

I will only buy the cases if they hold a stuffed board with PCB-mount pots.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: fucanay on April 25, 2007, 03:28:10 AM
I ordered the solder lug version from small bear. There doesn't seem to be a whole lot out there without having to get involved in another omeg group buy, which didn't turn out so good last time. Not to mention, that soon there is going to be a nationwide shortage on 500k reverse log pots, thanks to this eq.

I don't know about the shipping to the rest of the world, but I got 12 of them shipped for $27USD.  Not too bad for the costliest parts in the project.

Matt
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dissonantstring on May 02, 2007, 12:15:41 PM
Quote from: "fucanay"
Not to mention, that soon there is going to be a nationwide shortage on 500k reverse log pots, thanks to this eq.
Matt


hi matt,
this is the reason i contacted colin at audio maintenance to see if he could make them available for us with center detent for added nifty-ness  :thumb: (though they would be 470K rev. log).  it seems like there is more interest in PCB termination so i will pass this along to colin.  there should be enough interest in these pots since the number of PCBs that will be out there is quite staggering and hopefully this will benefit our DIY community as well as make it worthwhile for colin to stock these pots.
cheers,
grant
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: jensenmann on May 02, 2007, 02:11:15 PM
:thumb: good idea, Grant
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on May 02, 2007, 02:50:24 PM
I don't mind buying pots with solder lugs in a group buy (if it happens). I can still wire them to the PCBs.
It takes maybe one hour of extra work but as I said earlier, I insist on my front panel design which doesn't
look so crowded as the original. I am sorry Joachim, but it looks like you will have to design your own front
panel  :thumb:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on May 02, 2007, 02:59:44 PM
Quote
Purusha,
The original unit I have is pretty crowded but it NEVER bothered me.


I know what you mean, I used it before. But since I have the chance to decide how will
my Night cases look in my studio I will take the opportunity and make them less crowded
and improve the weakness on the original design  :wink:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dissonantstring on May 02, 2007, 08:11:30 PM
hi peter,
i wanted to make sure that these were the TYPE of pots that will fit your PCB:
(http://i97.photobucket.com/albums/l218/dissonantstring/om-01-024_3d_200.jpg)
the example pictured is a 16mm single gang pot with center detent, we would be asking for a 16mm single gang 470K rev. log pot with center detent.

i just want to clarify that colin (slenderchap) has offered to stock the 470K rev. log pots at his audio maintenance webstore making it easily available to all of us.  this is NOT a group buy, nor am i involved in the selling of this in anyway.  i just contacted colin to see if he could help us out since he's already well connected with omeg and carries many pots from them and he has generously offered to do so (for which i thank him).

regards,
grant
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on May 02, 2007, 09:00:39 PM
Grant, where is this audio maintenance webstore located?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dissonantstring on May 02, 2007, 09:36:43 PM
hi tat,
it's here: http://www.audiomaintenance.com/acatalog/potentiometers.html
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on May 03, 2007, 01:34:22 AM
Quote
i wanted to make sure that these were the TYPE of pots that will fit your PCB:


Grant,

Those look good, as long as the pins have a 5 mm spacing.

I also recommend the P20 (?) pots rather than the P16 pots, as the drawings I have seen on the Omeg site are a bit confusing, giving the P20 dimensions as 15mm & the P16 dimensions as 12.5 - 15 for the shaft centre to PCB pin "shoulder" i.e. the height from PCB top to shaft centre.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on May 03, 2007, 01:45:18 AM
You may want to try one first & see if the center point is accurate. Using 470k in place of the 500k may throw things off a bit... unless, hmmm... maybe you could add a resistor to one leg to adjust the center (FLAT) point :idea:

Quote
OK,
I just set ALL the bands of one channel to the center & got readings between 46k & 48k... 3 out of the 5 were closer to 47k.

So 47k it is @ the mid point.

Kevin
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on May 03, 2007, 05:10:11 AM
Quote from: "dissonantstring"
hi tat,
it's here: http://www.audiomaintenance.com/acatalog/potentiometers.html


Thanks  :thumb:

BTW, are they located in Europe or else where?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on May 03, 2007, 05:15:16 AM
Oh, they have £ next to their prices so it must be in UK  :green:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dissonantstring on May 03, 2007, 01:05:46 PM
hi kevin,
unfortunately, since this isn't a stocked item for colin he would be ordering them special, so i would have no way of testing them prior to him ordering a batch.  he wants to get the specs right that's why i've been posting on this thread.

i believe you are right WRT the difference between values since the 500K rev. log pot adjusts the proportional-Q so the bandwidth might suffer slightly.  if a 470K pot were used then i believe the adjustments on the more narrow bandwidth settings would not be as narrow(?) or in the opposite direction - wide(?)  somebody should step in if i'm on the wrong track here as i'd rather not add to any confusion or start thought that's horribly wrong. :oops:

as for the center point, i have no clue really.  what would actually be affected by the different value of resistance of center?   the value might be different, but the center is still the center right? :?
so those who use a 470K rev. log pot would just not get the most narrow or wide bandwidth settings of the proportional- Q on the frequency they are adjusting.
i like your idea of adding a series resistor to compensate for the 470K pot.  will this actually work?
cheers,
grant
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Slenderchap on May 03, 2007, 01:32:32 PM
Given the 5% tolerance of the mechanical rotation and the 20% electrical tolerance of an alpha electric pot it is probably all a bit vague as to what the exact value is at the centre point...... you would probably get the same value across a batch..... but it's anybody's guess between batches.

Combined with the fact that reverse log pots from different manufacturers have different laws [hence why they sneakily call them "audio" laws] you cannot even compare manufacturers.

We can have a set of samples made if you wish.

Colin
www.audiomaintenance.com
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on May 03, 2007, 05:23:11 PM
ATTEN:!:
About the Alpha pots from Small Bear -

I just measured several of these & they range from 450k to 490k.
The "CENTER Points" measured between 75k & 85k.

:shock:


All these pot will "Work"
I'm just reminding everyone of where my Original units FLAT Point is.

The circuit was designed around this I'm sure... when the knobs are centered, that band is "FLAT". This is at 47k.

I do not think other pot values will affect performance... just perception of.

The only reason I'm driving this point is because the PCB mount pots can not be rotated to adjust for the center point... they're stuck there.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: fucanay on May 03, 2007, 05:47:29 PM
Quote from: "khstudio"

The only reason I'm driving this point is because the PCB mount pots can not be rotated to adjust for the center point... they're stuck there.


True, but you could always just move use the set screw on a knob to adjust for this, right? That's assuming you used knobs with set screws I suppose.

But this does raise an issue about how much you can cut or boost if the centers (47k) are not at the correct place in the rotation. Out of curiosity, how many of the original pots did you check in terms of the center position value? EDIT: Oops, I just read this at the top of this page.

It seems to me that this could be a poor design if the pots are needing to be a very specific value when most are in the 10-20% tolerances. Or am I not understanding this right? Did you see a part number or manufacturer on the original pots?

Matt
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on May 03, 2007, 05:55:35 PM
Quote from: "fucanay"
It seems to me that this could be a poor design if the pots are needing to be a very specific value when most are in the 10-20% tolerances. Or am I not understanding this right? Did you see a part number or manufacturer on the original pots?

Matt

Perhaps this is the moment to skip all-things-pot & focus on rotary switches from now on ?
What do people think, how many taps would be acceptable ? Have some 12-pos. rotary switches here, but that might be too rude I'm afraid...
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: fucanay on May 03, 2007, 06:00:15 PM
Quote from: "clintrubber"
Quote from: "fucanay"
It seems to me that this could be a poor design if the pots are needing to be a very specific value when most are in the 10-20% tolerances. Or am I not understanding this right? Did you see a part number or manufacturer on the original pots?

Matt

Perhaps this is the moment to skip all-things-pot & focus on rotary switches from now on ?
What do people think, how many taps would be acceptable ? Have some 12-pos. rotary switches here, but that might be too rude I'm afraid...


If you could figure out what they all needed to be to gain the gain steps where you wanted them, I think it would be a good idea. And just imagine how great it would be for recall purposes. But of course sometimes you want a half db cut or something and this wouldn't be good for that.

Seems that the best solution is the right pots, but maybe that's impossible.

Matt
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on May 03, 2007, 06:13:31 PM
Quote from: "clintrubber"
Quote from: "fucanay"
It seems to me that this could be a poor design if the pots are needing to be a very specific value when most are in the 10-20% tolerances. Or am I not understanding this right? Did you see a part number or manufacturer on the original pots?

Matt

Perhaps this is the moment to skip all-things-pot & focus on rotary switches from now on ?
What do people think, how many taps would be acceptable ? Have some 12-pos. rotary switches here, but that might be too rude I'm afraid...


Good idea but your NEVER going to fit 12 Lorlins acrossed the front... what else is there that's cost effective?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on May 03, 2007, 06:20:41 PM
Quote from: "khstudio"
Good idea but your NEVER going to fit 12 Lorlins acrossed the front... what else is there that's cost effective?

Staggered perhaps ? Maybe case-meister Purusha can do some magic tricks with the parallel front panel he usually uses - space it a bit further away so that say all odd rotaries are directly mounted on the front panel and the even ones on the mentioned additional panel ?  

Must admit I have some mini-Elma's here, so that would work fine already as is.

But I'm not sure if 12-pos would be enough.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: jdbakker on May 03, 2007, 06:48:47 PM
Quote from: "khstudio"
Good idea but your NEVER going to fit 12 Lorlins acrossed the front... what else is there that's cost effective?

Has anyone ever used the Grayhill 56-series (or other half-inch rotaries) ? It would appear that Purple Audio use 'em (http://www.purpleaudio.com/resource/Brange.html), so they might not be total crap. Digi-Key stock 'em (GH5601-ND). At [email protected] / [email protected] they're not as cheap as the Lorlins, but not quites as expensive as the Elmas.

JDB.
[the ITT/Cannon half-inch switch (Digi CKN6049-ND) is somewhat cheaper]
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: fucanay on May 03, 2007, 07:23:24 PM
Quote from: "jdbakker"
Quote from: "khstudio"
Good idea but your NEVER going to fit 12 Lorlins acrossed the front... what else is there that's cost effective?

Has anyone ever used the Grayhill 56-series (or other half-inch rotaries) ? It would appear that Purple Audio use 'em (http://www.purpleaudio.com/resource/Brange.html), so they might not be total crap. Digi-Key stock 'em (GH5601-ND). At [email protected] / [email protected] they're not as cheap as the Lorlins, but not quites as expensive as the Elmas.

JDB.
[the ITT/Cannon half-inch switch (Digi CKN6049-ND) is somewhat cheaper]


I just upgraded my green pres to use the grayhills, but I'm having a hard time finding decent knobs for the 1/8 inch D shafts. They are really small and kind of a pain to solder the resistors to, but not impossible. I wouldn't want to have to pay $120 for switches on this though.

Matt
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on May 03, 2007, 07:43:05 PM
A quite poor solution to the rotary-size problem would be a 2RU case... Just mentioning it....
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on May 03, 2007, 07:59:35 PM
I have good news for ya. You can squeeze all 12 lorlins on my front panel design  :thumb:

I measured it so it's possible... if 12 pos is enough.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Slenderchap on May 04, 2007, 02:26:33 AM
Checked a few 470k rev log P16's yesterday.....

Track value 440k - 490k
Centre value - 45-53k

(centre is "by eye" as these pots didn't have a centre ident)

Colin
www.audiomaintenance.com
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on May 04, 2007, 03:31:53 AM
Quote from: "Slenderchap"
Checked a few 470k rev log P16's yesterday.....

Track value 440k - 490k
Centre value - 45-53k

(centre is "by eye" as these pots didn't have a centre ident)

Colin
www.audiomaintenance.com


That center value looks VERY good... are you sure?
If so, they seem like excellent candidates.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on May 04, 2007, 03:51:53 AM
Quote from: "Purusha"
I have good news for ya. You can squeeze all 12 lorlins on my front panel design  :thumb:

I measured it so it's possible... if 12 pos is enough.

Hey that's good news.

Now for the next hurdles, that 12-pos is indeed a bit limited. Let's see if these could be taken as well:

Range is -19 .. +20 dB (based on the 5k62, 56k2 & 500k-pot). We want to have a neat 0dB mid-position so a 12-position rotary could do for instance (first simple approach replicating the range the pot gives) boost in (6) 3.33dB steps and cut in (5) 3.8 dB steps.
I think that s*cks, not ?

Alternative is to say that we never need the full range and go for instance for -10 .. + 12 dB in 2 dB steps.

Or some trickery with an added 'range'-switch (say a SPDT on the 56k2 or ...) which can give all kind of possibilities but loses the elegance of the design as it is now.

Hmmm.....


Regards,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: mick on May 04, 2007, 04:14:42 AM
Am I missing something, didn't Kevin just use switches on his 'air band' only unit, that way you know only the bands your using are in, when you've got 6 bands if there not on the spot for '0' it will be a pain to set up from scratch... wouldn't it ? I don't know that's why I'm asking.

Mick
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on May 04, 2007, 04:22:31 AM
Quote from: "mick"
Am I missing something, didn't Kevin just use switches on his 'air band' only unit, that way you know only the bands your using are in, when you've got 6 bands if there not on the spot for '0' it will be a pain to set up from scratch... wouldn't it ? I don't know that's why I'm asking.

Mick

To prevent any eventual confusion: the rotary switches I've been mumbling about concern replacements for the pots, not any enabling or disabling of EQ-bands.

Reasons for wanting to use rotaries:
* 'proper' stereo-use of this EQ
* rev-logs would require 'tuning' to have a proper flat-band mid-setting

Problems with rotaries:
* economical models give (too) large stepsizes
* cost

Discussion:
* can we live with 2 or 3 dB stepsizes or is this an EQ that you rarely want to use for more than some +/- 10dB ?

Bye,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Slenderchap on May 04, 2007, 04:23:19 AM
F.Y.I.

Sample batch of 20 x 470k rev log P16's

Average value 457.7k
Centre point average value 52.7k (centre "by eye")

Colin
www.audiomaintenance.com
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on May 04, 2007, 04:26:11 AM
Quote from: "Slenderchap"
F.Y.I.

Sample batch of 20 x 470k rev log P16's

Average value 457.7k
Centre point average value 52.7k (centre "by eye")

Colin
www.audiomaintenance.com

Thanks for the stats. What's the spread ?

Regards,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: mick on May 04, 2007, 04:35:13 AM
Yes sorry Peter I was talking more about pots and centre indents, but I believe we seem to be addressing the same point.

Mick
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: fucanay on May 04, 2007, 12:28:38 PM
Well, since I already have the small bear pots, I'm just going to use those and twist the knobs until it sounds good. It' won't be surgical EQ, but it'll be fine for my uses. If I get real ambitious, I may look for the 47K centers and make my knobs align it to center and live with the results. Personally, I was looking for a cheap EQ and if I get caught up in expensive pots it won't be that anymore.

Still interesting to hear how this all pans out though. There is always that one elusive part and it's cool to see how people get around it.

Matt
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on May 04, 2007, 02:04:58 PM
Quote from: "fucanay"
Well, since I already have the small bear pots, I'm just going to use those and twist the knobs until it sounds good. It' won't be surgical EQ, but it'll be fine for my uses. If I get real ambitious, I may look for the 47K centers and make my knobs align it to center and live with the results. Personally, I was looking for a cheap EQ and if I get caught up in expensive pots it won't be that anymore.

Still interesting to hear how this all pans out though. There is always that one elusive part and it's cool to see how people get around it.

Matt


This is where I stand also... I've already bought 50+ Alphas from Small Bear.
Quote
look for the 47K centers and make my knobs align it to center

My thoughts too + keeps the cost of this Q VERY low.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on May 09, 2007, 05:06:02 PM
Looking at the cct, there is a way of getting the centre detented pots to be flat, no matter what the tolerance.

My maths might not be correct, so if you know better, please chime in.

The gain of each stage is set by the combo of the 5k6 + the centre value of the 500k pot divided by 56k2 (R30), if this is an adder, right? So (5k6 + 47k)/56k2 = 0.94. Nearly a gain of 1. (this measurement actually gives a 1/2dB error)

That why the 47k centre position that Kevin measured was important.

Well, from the above sentence, we could vary the 5k6 resistor to compensate for the pot tolerance. So if one stuck a 10k trimmer in instead of the 5k6, one'd be able to trim each stage's gain to as close to 1 as dammit. Pull out the trimmer & put in the closest resistor value.

Ideally the centre position should measure 50k6 for a gain of 1.

So we could use Omegs' fine 470k Rlog pots & still be sure that the centre position would be flat.  The gain & cut at the extreme ends of the pot would not be exactly the same but if you are boosting 15db with this wide Q cct, you'd better have some real headroom in your system!

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on May 09, 2007, 05:16:33 PM
Quote from: "peterc"
Looking at the cct, there is a way of getting the centre detented pots to be flat, no matter what the tolerance.

Well, from the above sentence, we could vary the 5k6 resistor to compensate for the pot tolerance.

Sure, as implied more or less clearly in the various previous discussions,  this will work.
It's a 'calibration' in one spot, obviously no guarantees about the 'law' to the left & the right (the 'law-signatures' might be shifted w.r.t. each other; note that 'loggish laws are usually 'piece-wise lineair').
But it's a calibration in the most important spot (0 dB), so that's definitely nice.
The max boosts & cuts will also vary between bands though, but that won't be too big a problem.

So this might all be fine enough and/or hardly noticable. It's also about the best that could be done given the situation, so nice that that 'best reasonable effort' might most likely be enough  :wink:  :thumb:


BTW, I feel this whole circuit could have better used some other boost/cut scheme than the present method. For instance summing the bands 'volumepot-wise' could make the summing circuit less sensitive  to the pot-value of each band. Most likely even totally insensitive to it. And if the circuit as is sounds nice I guess that 'converted' one will as well.
 
But that's all for another day; I'll be happily building this EQ as it is (thanks all you-know-who for making it happen).  

Regards,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: PimD on May 10, 2007, 05:43:29 AM
Quote from: "peterc"
I used Kevins last schematic....... It may sound a bit general, but thats all I have!

I added
4 x22R resistors,
4 x 22uF/25v caps,
12 x .1uF caps (2 per IC) &
2 x 22uF/63v caps for the input.

Peter


I had a look at the schematic and pcb overlay, but i couldn't find the 4 22uF/25V caps. where do they go, and wich type is it?
And also on the schematic it says 9x .1uF caps, adding 12 would make 21, i can only find 19.
Will be ordering parts soon, at musikding.de
can i use a Silver Mica for the 22pF (it's the only one they have)

Pim
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on May 10, 2007, 05:59:16 AM
Quote from: "PimD"
can i use a Silver Mica for the 22pF (it's the only one they have)

Pim

I didn't check the schematic, but how many are needed ? IIRIC these silver mica's are not cheap. The tiny small ceramic ones will be fine (black stripe: zero temp-co), PM me if you can't find these.

Bye,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: PimD on May 10, 2007, 08:38:47 AM
I need only 2, so the costs won't be too big, (about €1) so not a real problem then, just wanted too know if could use them.

Pim
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dissonantstring on May 10, 2007, 11:56:55 AM
hi peter c.
thanks for the explanation which seems very reasonable as a "calibration" procedure for the 0dB center point of each cut/boost pot.  would it be reasonable to assume that it would be the same to measure the center detent of the pot and just calculate the difference in resistance needed to obtain the "ideal" 50K6 ohm for a gain of 1 - then replace the 5K6 with whatever your calculation result is?
for example:
i have a 470K rev.log pot with a center detent at 43.2K.
50K6 - 43.2K = 7K4 ohms resistance to obtain a gain of 1.

or would a trim pot be necessary in this case for reasons i'm just too "green" to see? :green:
and what happens if the center detent of the pot is more than 50K6?
i know there is probably too much discussion about this and we should really build and test before going off on a tangent, but i'm curious.
thanks.
-grant
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on May 10, 2007, 03:07:55 PM
Quote
i have a 470K rev.log pot with a center detent at 43.2K.


The total of this value + the series resistor (currently 5k6) should be 56k2. So in this case the 5k6 should be changed to 56k2 - 43k2 = 13k.

Quote
and what happens if the center detent of the pot is more than 50K6?

As long as the centre value is not more than 56k2, this method will work.


Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dissonantstring on May 10, 2007, 08:35:41 PM
Quote from: "peterc"

The total of this value + the series resistor (currently 5k6) should be 56k2. So in this case the 5k6 should be changed to 56k2 - 43k2 = 13k.

As long as the centre value is not more than 56k2, this method will work.

Peter


so i think these omeg 470K pots from colin will work out fine since colin has stated the average center is about 52K7 and all were between 45K and 53K from the batch he tested (so lets hope its the same in the future).  So we can use these pots with a 0dB center detent by just adjusting the 5K6 resistor of each pot. :thumb:

thanks for clearing that up peter!  
regards,
grant
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on May 11, 2007, 01:16:45 PM
Pics of the protoype PCB's

http://www.groupdiy.com/index.php?topic=266520&sid=d3179c5e8dbfd31d86f7c5a5b1857bd7#266520
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on June 04, 2007, 01:45:40 AM
UPDATE:

http://www.groupdiy.com/index.php?topic=271167#271167

(http://www.khstudio.us/Nite-EQ-V1.jpg)
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: mikeyB on June 04, 2007, 06:37:04 PM
:razz: yumyumyumyumyumyumyumy :razz:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dissonantstring on July 18, 2007, 02:04:57 PM
for those looking for the overlay for Peter C.'s PCB and excel BOM:

here (http://www.groupdiy.com/index.php?topic=279523#279523)

also...

peter,
did you ever receive those center detent 470K pots from colin?  How did they work out?
cheers,
grant

edit: 470K pots not 4K7 :oops:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Godders on July 18, 2007, 02:09:23 PM
I don't know if you two are getting sick of hearing it but thanks a TON for all your work on this guys.  :thumb:

Cheers

Nick
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on July 18, 2007, 03:20:47 PM
Colin sent a set of 470k pots but they STILL have not arrived here yet. Our postal system is about as disfunctional as a politician. I hope they arrive soon.

Quote
I don't know if you two are getting sick of hearing it but thanks a TON for all your work on this guys. Heck Yeah!


 :grin: sigh..... :grin:

No problem at all.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dissonantstring on July 19, 2007, 11:56:00 AM
hi peter,
i hope that you get to try out those pots that colin sent over.  i'd really like to use those in my build so hopefully they work out well.
i'd also like to add to nick's comments and say that this is a great EQ project that is possible only because of kevin's research and your pcb layout and initiative to offer these boards to all of us.  so thanks again kevin and peter! :guinness:  :guinness:
cheers,
grant
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dissonantstring on July 20, 2007, 09:22:47 PM
hi peter,
just started looking over your BOM and noticed that there are two R35 but no R37 (series resistors).  is one of the R35 supposed to be R37 at the 5K62 value?  also, is the 2 pole/6 position rotary switch shorting or non-shorting (or does it matter)?
thanks!
-grant
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on July 21, 2007, 12:17:43 PM
Quote from: "dissonantstring"
hi peter,
just started looking over your BOM and noticed that there are two R35 but no R37 (series resistors).  is one of the R35 supposed to be R37 at the 5K62 value?  also, is the 2 pole/6 position rotary switch shorting or non-shorting (or does it matter)?
thanks!
-grant


I'm 99% sure it's shorting :?
We talked about it earlier in this thread.

YES on the resistors... the prototype had no R37 & 2 R35's - they are BOTH 5k62.

It is now fixed on the NEW PCB.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dissonantstring on July 23, 2007, 12:19:16 PM
Quote from: "khstudio"
There's a Grayhill 2x6 switch (P# 71BF30-01-2-06S)
K


Quote from: "electrog"
i believe the "s" at the end of the grayhill part number denotes shorting. non-shorting types have part numbers ending in "n".
david


hi kevin,
doh!! :oops:   i should have known this was probably answered before.  stupid and lazy me.  sorry about that and thanks for answering the R37 question as well.  good to know it's corrected on the new PCB.
cheers,
grant
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sysexguy on July 29, 2007, 10:49:31 PM
I have an idea....... :twisted:

If I use all 6Pdt grayhills with a resistor network and strap the left and right side in stereo, the left side controls could be the coarse tuning and the right side, the fine tuning. (6positions on each would give 36 steps of resolution per band)

So a crazy idea that requires $120+ of switches but might just be awesome. Am I risking major crosstalk or other problems by having leads x-crossing along the front panel???? Any other observations?

If it would work, the unit could be used as a mastering or output bus stereo eq with repeatability and confidence......I've had pots drift as time passes and the racks get hot......and then one only notices the problem at a bad time :roll:

Andy
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: discobloud on August 01, 2007, 02:57:27 PM
just wondering if anyone is willing to share a BOM with digikey/mouser numbers?  It's not that i'm lazy, sometimes it takes me an hour figure out which part to use... if not i understand.  monstermark[at]gmail[dot]com

thanks again to everyone for the time put in

mark
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MattiasC on August 02, 2007, 12:49:55 AM
BOM questions:

1)  What does cbyp mean?

2)  What's the difference between a .1uf "ceramic/poly" cap and the .1uf poly cap?  

3)  Would this work for the .1uf "ceramic/poly" caps?  

http://www.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=445-2613-ND

Thanks!
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on August 02, 2007, 01:56:40 AM
I would be also greatful for the BOM with digikey/mouser, Slenderchap numbers  :thumb:  :thumb:  :thumb:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Godders on August 02, 2007, 03:04:49 AM
Quote from: "MattiasC"
2)  What's the difference between a .1uf "ceramic/poly" cap and the .1uf poly cap?
I took it to mean you can use either a ceramic or a poly cap in that location.

Cheers

Nick
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on August 02, 2007, 03:11:05 AM
Matthias

"cbyp" stands for C bypass, but cbyp is the way the name comes up in my PCB programme.
Quote
"ceramic/poly" cap and the .1uf poly cap?


I use either for the power rail bypass caps (cbyp above). I prefer the sound of poly caps in the signal path, hence the 2 different types.

The listed cap looks fine.

Regards
Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on August 02, 2007, 10:57:21 AM
Can someone please help me to get the ordering code from Small Bear or anywhere else for the center detended pots?
I need 72 pcs and can't find these pots anywhere...  any nice place in Europe to get these?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MattiasC on August 02, 2007, 11:37:20 AM
Thanks Peter.  I'll go with these (much cheaper) polys .   I don't anticipate 48v usage but I'm buying the higher rated caps just in case.

http://www.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=P4725-ND

Got the boards yesterday, looking good.  
 :thumb:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Godders on August 02, 2007, 01:09:46 PM
Quote from: "Purusha"
Can someone please help me to get the ordering code from Small Bear or anywhere else for the center detended pots?
I need 72 pcs and can't find these pots anywhere...  any nice place in Europe to get these?
Hi Tat, I don't know if anyone's found an easy source for 500K, rev log with center detent.

Smallbear said he'd get some for us but the minimum order would be 1000 pieces.

Omeg has 470K rev log with center detent.

There are a few sources without the center detent (Banzai, smallbear, das musikding).

Cheers

Nick
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on August 02, 2007, 01:19:04 PM
Hello Nick,

I want the center detended for sure  :thumb:

I am waiting now for the price quote from Omeg but would be more interested in the group buy if it happens.
I think there is enough boards out there to cover 1000 pots  :green:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dissonantstring on August 02, 2007, 01:22:54 PM
guys,
hold tight if you really want center detent 470K rev. log pots.  peter has already gotten some samples from colin at audio maintenance and will hopefully be able to let us know how well they work in the circuit.  colin has told me that if peter thinks they will work then he can put an order in to omeg for these pots, but it will take about 3 weeks to get them from the order date.  
i don't think that's long to wait since they will be center detent and i'm sure colin will let us know if he makes them available through audio maintenance.
i really like center detent for eq cut/boost so hopefully we'll be able to get these from colin.
regards,
grant
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Godders on August 02, 2007, 01:27:22 PM
OK, cheers for that grant. :thumb:

Nick
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Slenderchap on August 02, 2007, 03:13:21 PM
We will make these available in the on-line store.... the only sticking point is the shaft diameter.

Normally all the pots we stock have 4mm shafts (and 7mm bushes)....

If we get 1/4 inch shafts (which I am sure you would all prefer for this project as there is a much wider selection/availability of knobs) then the bushes will be 3/8 inch diameter.

Unfortunately all the holes in the Purusha cases are 8mm so you would need to ream out the holes to fit the pots.

Ream the bushes and have a good selection of knobs ?

or

Have metalwork as supplied and search harder for knobs ?

Opinions ?

Colin
www.audiomaintenance.com
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on August 02, 2007, 03:31:03 PM
I'd go for re-drilling the holes  :thumb:

I already ordered 84 knobs with 6.3mm shafts  :oops:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dissonantstring on August 02, 2007, 03:33:11 PM
hi colin,
just my 2 cents, but i think enlarging the hole for the pot to 3/8" bushing size would be a better option than trying to obtain less available knobs with the 4mm shaft diameter.  i had to enlarge the hole in purusha's front panel for my MC76 case i bought from him and it wasn't a problem at all.  just drilled it out with a stepped bit.

my vote is for a pot with the 3/8" bushing size with the 1/4" shaft diameter.

thanks for checking with us.  anybody else have opinions?
cheers,
grant
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on August 02, 2007, 03:36:14 PM
I USED THESE FOR EVERYTHING:
DIGIKEY

P4525-ND     CAP .1UF 50V STACK METAL FILM     ALL .1UF

P4548-ND    CAP 1.UF 63V STACK METAL FILM    ALL 1UF


Some people do like Ceramic for the Power rail filtering

Also, I installed the inductors just to be safe but IT WILL WORK without them.
Maybe one of you guys with some GOOD TEST EQUIPMENT & Knowledge can test it with & without to see. It was mentioned that these MAY have been added because of the ORIGINALS switching power supply.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on August 02, 2007, 03:39:27 PM
I agree with Grant, if you increase the drill by 0.5mm everything goes very smoothly.
Also the pots in my cases are mounted behind the front panel so maybe
there is no need to drill up the front panel as well.

What is the length of the bush part?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on August 02, 2007, 04:42:42 PM
I've had the Omeg parts in for a couple of days now & both tests have seemed fine. They fit the board perfectly & are solidly made.:thumb:


I did not check the resistance in the centre position or did any trimming, which I will do when I get some time, but I liked the feeling of the Omeg part.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: lookn4tone on August 02, 2007, 04:51:47 PM
What about the issue with the by pass toggle interfering with the vari selector switch in the cases?  

Are the pots from AML pcb mount or panel mount?  From what I saw, it looked like the PCB's would have to be mounted to the rack base and then wired to panel mount pots (same for the switches).
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on August 02, 2007, 05:03:00 PM
Quote from: "lookn4tone"
What about the issue with the by pass toggle interfering with the vari selector switch in the cases?


Problem solved nicely with a special bracket  :thumb:

Quote
Are the pots from AML pcb mount or panel mount?  From what I saw, it looked like the PCB's would have to be mounted to the rack base and then wired to panel mount pots (same for the switches).


In my cases all the pots and switches have to be wired manually. A little more work but in this way the fronts look more hot  :twisted:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: lookn4tone on August 02, 2007, 05:51:58 PM
Hey Tat

I'm not complaining; I'm just trying to make sure the pots work with your cases.  We need to make sure that, before an order is placed for 1000 pieces, they are the right ones.

I bought two of your cases for the build.  And they do look great.  Can't wait to have them in hand.

Now, about those center detent, panel mount pots....

Steve
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on August 02, 2007, 07:53:09 PM
Hey Kevin,  what about the lytics... Nichicons, or it doesn't matter so much?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on August 02, 2007, 07:58:39 PM
Quote from: "Purusha"
Hey Kevin,  what about the lytics... Nichicons, or it doesn't matter so much?


I have always liked Nichicon PW's in the audio path!!!

Power Supplies... Low Imp. High reliability & LONG Life.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on August 02, 2007, 08:00:19 PM
Hey TAT,
About the face plate... send me whatever you can.
Something I can PRINT OUT &/or EDIT would be cool. :wink:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Slenderchap on August 03, 2007, 08:36:07 AM
OK.... we will get them with 1/4 inch spindles and 3/8 inch bushes....

How long do you want the spindle.... they can be 60mm long and then you can just cut them down to a short size to suit.

Colin
www.audiomaintenance.com
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on August 03, 2007, 08:56:30 AM
Will the spindles be from metal or plastic?

I hate to cut metal ones... plastic is no problem. In my cases the ideal would be 17mm from the flat
part of the pot to the end of the spindle (this includes the part where the screw comes on).
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on August 03, 2007, 09:01:15 AM
Quote from: "Purusha"
Will the spindles be from metal or plastic?

I hate to cut metal ones... plastic is no problem. In my cases the ideal would be 17mm from the flat
part of the pot to the end of the spindle (this includes the part where the screw comes on).

Nah... while plastic will be fine, the hassle to cut metal is just once, but turning plastic-shaft-pots is for the rest of the life of the unit  :wink:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on August 03, 2007, 09:09:09 AM
I prefer the metal ones but only if they can be 17mm from the flat part  ... that is 2mm more than the regular 20mm Alpha pots  :thumb:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Slenderchap on August 03, 2007, 09:29:18 AM
They will be plastic (nylon)... with a "D" shape

Colin
www.audiomaintenance.com
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on August 03, 2007, 09:33:15 AM
Can we skip the D shape? I have ordered 84 knobs with round shaft already  :?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Slenderchap on August 03, 2007, 10:15:26 AM
OK.... round.... people who need "D" will just have to file them flat.

Colin
www.audiomaintenance.com
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Godders on August 03, 2007, 10:34:31 AM
I'm really going to throw a spanner in the works and say "whatever".  :green:

Thanks again Colin.

Cheers

Nick
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on August 03, 2007, 10:42:46 AM
:thumb:  :thumb:  :thumb:

Colin, any idea about the price yet?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Slenderchap on August 03, 2007, 11:18:18 AM
They should be the same as the other single gang + Ident pots (but I'll confirm on Monday)

(1+) £1.43 each
(5+) £1.14 each
(50+) £0.97 each

Prices exclude freight and VAT [if applicable].

Colin
www.audiomaintenance.com
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on August 03, 2007, 12:07:20 PM
For me this comes around 1.8€ a piece (VAT included). I'll send the courier to pick
them up when ready just to avoid the expensive UK shipping options?  :thumb:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Jed on August 03, 2007, 12:47:30 PM
Somehow I had missed this thread for a few days...

Anyhow, I just posted this in blackmarket. But it should be here.

Quote
So I've spent a bunch of time on Mouser with the BOM over the last few days and I thought I'd share so A) folks don't have to reinvent the wheel, and B) I can get a critique on some of the part choices I was making.

[REMOVED]

Of note:
1. I haven't placed an order at mouser, just trying to get a good parts list together so that people can use their "project manager' to make ordering a little quicker.
2. When picking resistors I was looking at tolerance first (trying for .1% as possible) and watt rating second. So there's some 1/10th watt resistors in there and I don't know if they are too wimpy for this circuit (I haven't tried to do any math to figure out the current draw). People might be better off with 1% 1/4 watt.
3. I didn't do this for the PSU yet.
4. I suck at figuring out switches. It looks like the part that Peter had listed from Farnell is now discontinued. Does anyone know a replacement?

Hope this helps some folks, and I hope to learn something from any discussion which ensues.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dissonantstring on August 03, 2007, 03:29:19 PM
hi jed,

2) i would just use 1% 1/4W resistors and match them with your ohmmeter. why spend the money for expensive 0.1% resistors with only 1/10W ratings?

4) just measure the pitch (space betwen pins) and find the datasheet on the mouser website and pick a good candidate.  I'm sure there are several pushbutton switches that will work.  if using purusha's case then you'll need toggle switches as the front panel is made for toggle switches.  just fly some leads to them.
regards,
grant
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Jed on August 03, 2007, 04:22:53 PM
Good call, Grant. I've updated for 1/4 watt here:
[REMOVED]
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: matta on August 03, 2007, 04:39:12 PM
Something to be aware of....

If I'm not mistaken (if I am please clear it up) Purusha made his Night Eq racks for the ALPHA pots which have a smaller shaft diameter to the OMEG's which would mean those who have bought racks would have to redrill the mounting holes... a PITA, but may be worth it for  better quality pot.

Cheers

Matt
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on August 04, 2007, 04:59:46 AM
Dear DIYers:

Please don't get scared by the idea to re-drill the pot holes in the fronts  :grin:
It's pretty easy! You just need to go step by step by increasing the drill for
0.5mm or even less if you can. Also the front panels maybe won't be needed
re-drilling as they are further away from the pot.

Let me remind you that this is DIY, remember! :green:
So you should have some basic skills to do something like this, right?  :razz:

Jed: I saw you have 14 rev log pots mentioned in the parts list for two channels. I think 12 is enough  :thumb:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Jed on August 05, 2007, 12:46:29 PM
Thanks for that catch, Purusha.  I had done a quick little excel formula to get some extra parts...

While we're at this, do you have suggestions for toggle switches that will fit your case?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on August 05, 2007, 12:54:16 PM
I just buy them at local store. Nothing special, standard Miyama toggles will do.  :thumb:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Jed on August 05, 2007, 01:46:34 PM
Thanks, Purusha. I'll just wait until the case arrives to find something that fits.

I've attempted to put together a BOM / Mouser list for Peter's New PSU. Does anybody want to double check that I've got things right?

[REMOVED]

Peter, what's the black box? Voltage adjuster? Do you have something specific that fits that pin spacing?

Also -- will the power transformer I've selected fit the bill?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on August 05, 2007, 03:30:18 PM
I've updated this BOM slightly, have a peek here:

http://www.twin-x.com/groupdiy/index.php?cat=10096

The square box is a bridge rectifier, 1A 400v or greater will do.

See the BOM for some mains transformer examples.

I have also updated the overlay .pdf to show the Bridge.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on August 06, 2007, 11:22:47 AM
Uh, I just realized there's no level-control on this EQ (yes, a bit fast...  :oops: ) to compare flat & EQ'd.


Something else, I saw in the pics that Godders linked to
( http://cgi.ebay.com/Nightpro-EQ3-D-Dual-Channel-Dimensional-Equalizer_W0QQitemZ140142298929QQihZ004QQcategoryZ23788QQcmdZViewItem )
that this design is patent applied for (the sweetwater info even says patented). Has the patent-# emerged here yet ? Could be an interesting read. And/or any manual-scans that someone knows of ?

Thanks / regards,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on August 06, 2007, 03:25:31 PM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: okgb on August 06, 2007, 03:55:14 PM
Hey Kev  , you were going to post or mention your " air only  " variation ?
not sure how different it is , less the parts but , please lay it on us

thanks & regards Greg
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MattiasC on August 06, 2007, 05:28:26 PM
Is an 18-0-18v toroid acceptable for this or can I get by with a 15-0-15v?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on August 06, 2007, 05:30:24 PM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on August 06, 2007, 05:32:36 PM
Quote from: "MattiasC"
Is an 18-0-18v toroid acceptable for this or can I get by with a 15-0-15v?


I didn't like the 18v. The regs got VERY HOT.
15v works great & for some reason sounded better... less "Stressed" sounding to me. :?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on August 06, 2007, 07:12:03 PM
Quote from: "khstudio"
There's a BYPASS for comparing.

Sure, but as we know boosting any band increases level so makes most of whatever boosting was done 'better' in our perception.
Hence the 'need' for a level-adjustment to make a fair judgement possible: was the new non-flat EQ-setting really an improvement or did it sound better because it was louder ? (sanity check)
Actually strange the original didn't already have this...

Adding a level-control (1) would have been easy (so a plus), (2) would have changed the 'original' appearance (negative) and (3) would have given an even more cramped front panel (negative), but (4) would have made it easier to spot the versions of the eBay-cigarette-lighter-solder-cloners (positive side effect)...

Quote
#3 - I THINK it's just Pending.

OK, I understand. The rear panel legending seems indeed more solid evidence than the sweetwater-quote.

Quote
#4 - I'm not sure I should say this or not but Nightpro (or at least the "AIR" technology) was purchased by BOSE.

Then that must be because of a granted patent I guess, otherwise I don't see why they would transfer any money.
Note this is meant in all respect: it's not clear to me what kind of 'technology ' is going on here. Active filter design as we knew it already I'd say. Mackie had something of 'air' as well (15kHz bandpass I thought) and ther have been more ideas towards the same goal.
But the patent-world etc can be strange, so who knows. And please ignore the fact that I have the bad habit of being a bit itchy about people calling obvious things 'a new technique'  :cool:

Since the word is out there already, where did you hear about this ?

Regards,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on August 06, 2007, 09:43:43 PM
Trust me... it's not just volume boost that makes you like this EQ.
Yes, it's a WIDE Q but that's what's nice about it.

Quote
Since the word is out there already, where did you hear about this ?

Regards,

Peter


I can't say, sorry.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on August 07, 2007, 05:58:04 AM
Quote from: "khstudio"
Trust me... it's not just volume boost that makes you like this EQ.
Yes, it's a WIDE Q but that's what's nice about it.


Hey, I read your reply a few hours ago, just returned now and wanted to reply, but the stuff on which I wanted to reply is gone   :wink:
What to do now  :roll:

All fine, please be confident that my words above were not meant as criticism or such - just that in general it'd be a more 'honest' comparison when levels are unchanged.  


Quote
Quote
Since the word is out there already, where did you hear about this ?

Regards,

Peter


I can't say, sorry.


OK, I understand. I recall a conversation when we were doing a project for Bose - I asked something about this or that.
"I could tell you but then I have to kill you", was the reply. Note that things like this are funny but often also a method to hide that there's actually nothing special going on  :wink:

Which makes me wondering if ongoing 'patent applied fors' can be found somewhere - never thought about that before.  

Bye,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on August 07, 2007, 02:44:08 PM
I removed what I posted because of what you said in another thread.

I have misjudged people & especially their WORDING many times on the internet.

I do understand your point about the Volume levels & perception.
It's just a little late in the game... especially for those who bought cases.

If you REALLY wanted to compare - track to a computer & normalize the 2 tracks.

Lets move on :green:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on August 08, 2007, 08:06:25 AM
I am in for the group buy of those Omeg pots  :thumb:
Just got the price quote from Omeg and it's not even close to the price mentioned in the group buy.

Any confirmation on the price yet?

Only downside I see is that group buys tend to drag too long ...
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Slenderchap on August 08, 2007, 08:51:09 AM
I have ordered them already from Omeg....

If you want to do a "Group Buy".... be my guest... and I will cancel the order.

Colin.
www.audiomaintenance.com
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on August 08, 2007, 08:59:43 AM
Great news Colin! Sorry, I completely forgot that we are not doing the group buy through black market...  :oops:

At Omeg they said waiting time is 4 weeks so I guess it can't be that much longer for 1000 pcs, right?

You can send me payment details to my email. I can pay for them when you have the final cost together minus the shipping as I will send the courier to pick them up.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Slenderchap on August 08, 2007, 09:10:12 AM
I just stuck 500 of these on the back of one of our other Omeg orders.

I figured that a few people wouldn't want to wait so would be tempted into using the inferior quality Alpha pots from Great Bear?

Just to clarify.... all the Omeg pots are "conductive polymer"... we just refer to them as "Carbon" out of habit as they were originally simple carbon pots.... but all Omeg pots have been "conductive polymer" for many years.

Colin
www.audiomaintenance.com
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Purusha on August 08, 2007, 09:27:10 AM
I just sent you email with my order  :thumb:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sysexguy on August 09, 2007, 01:50:45 PM
Hi all, a couple of questions and notes:

1) gonna do the Omeg, easier and I my idea (5 pages ago) had a major blonde moment   :roll:

2) Can someone explain to me why c1/c14/c15 are so BIG??? similar coupling caps in my LA-2A are 0.1uf (sorry if this is NOOB 101)

3) This all came up as the 470uF/63V in the previously posted BOM will not fit, the leads require a re-drill (easy) and they take up about 3mm more in diameter. Plan B?

4) same BOM, the ceramic bypass caps in the mouser list are not conforming with the note  
Quote
For Ceramic caps try & use NPO/COG types rather than X5/Y7 types
Why is this suggestion made?

5) the filter cap array for the shelve won't have room for the .47 WIMA...I had to make a bridge and mount it on top (pic to follow)

6) the .1uF Wima's (signal caps) are quite tight especially the pair that lives close to the IC. one has to put them in together.....reminds me of my niece and nephew when they fight to sit in front of the computer  :roll:

Andy
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on August 09, 2007, 03:00:40 PM
What BOM are your referring to?
If it's NOT from KEVIN (ME) OR PETER.. I don't think it's been checked!!!

Quote
2) Can someone explain to me why c1/c14/c15 are so BIG???


The ORIGINAL UNIT used 25v/470uf in these spots.
I think Peter suggested 63v to be safe... but I can see your point the more I think about it.
A 470/63v would be HUGH for this spot on the PCB!

Quote
4) same BOM, the ceramic bypass caps in the mouser list are not conforming with the note
Quote:
For Ceramic caps try & use NPO/COG types rather than X5/Y7 types
Why is this suggestion made?

5) the filter cap array for the shelve won't have room for the .47 WIMA...I had to make a bridge and mount it on top (pic to follow)

6) the .1uF Wima's (signal caps) are quite tight especially the pair that lives close to the IC. one has to put them in together.....reminds me of my niece and nephew when they fight to sit in front of the computer Rolling Eyes

Andy


I had no problems finding (the correct) components to fit the PCB.

I take NO responsibility for BOMs or Parts list I didn't check!
I think the 470/63v caps may be a problem & ARE on the BOM I checked... sorry. I would stick with 25v caps in these spots unless you can find 63v caps to fit.

LOOK AT THIS PIC!

THE .22 & .47 ARE BOTH WIMA'S
c1/c14/c15 are 25v/470uf
The ALL fit!
(http://www.khstudio.us/Nite-EQ-V1.jpg)
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sysexguy on August 09, 2007, 03:14:12 PM
The BOM I was refering to is http://www.twin-x.com/groupdiy/albums/userpics/Nite_EQ_Parts_-_fIXED-MOUSER.xls posted on http://www.groupdiy.com/index.php?topic=22102&postdays=0&postorder=asc&start=405 pg 28.

I apologize if my post caused any offense (?). I am well aware that this is DIY and we are all responsible for our component choices and need to make intelligent decisions. I am also aware that DIY involves sometimes buying extra parts and carefully resoldering. In this case, I think I'll be fine as is but I thought it would be best to share my experience so that both myself and others could benefit.

I really appreciate all the efforts that went into making this project and in no way wish to imply that the project has any issues.  :thumb:

best,

Andy
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on August 09, 2007, 03:40:36 PM
I am NOT offended at all... I am also trying to save other of the same problem. :wink:

The PIN SPACING is correct on the BOM = 5mm
What is your pin spacing on the parts you ordered :?: c1, 14, 15

Quote
For Ceramic caps try & use NPO/COG types rather than X5/Y7 types   
   
This is CORRECT!

Quote
4) same BOM, the ceramic bypass caps in the mouser list are not conforming with the note
Quote:
For Ceramic caps try & use NPO/COG types rather than X5/Y7 types
Why is this suggestion made?


This is where the conflict lies!!!
The NITE EQ BOM (posted by Peter & myself) is NOT a MOUSER PARTS LIST :?

You said "the same BOM then you refer to a MOUSER parts list" ...
What Mouser parts list???

After Years of DIY I realize that ordering parts can be as hard as building.
There's MANY options, sizes & Types that do & don't work... it's part of the FUN. :razz:  Ordering parts is my least favorite thing to do but over the years I've gotten better at it. There's no getting around it.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on August 09, 2007, 03:46:02 PM
Andy

See the thread about the 63v caps, for Phantom protection. I used Rubicon YXF series which are 12.5mm diameter.

Check the BOM for pin spacing of the caps, if the pins are right, the cap should fit.

X5/Y7 are generally not used in better audio products, they are terribly non-linear.

If the .1uF are too big, make sure you are using 50v or 63v parts. These are smaller than 100v or higher. Some substrates are bigger than others, e.g. ceramic vs. poly.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sysexguy on August 09, 2007, 04:06:58 PM
Hi guys, thanks for the help, the list I linked was posted on this forum, took your BOM (?) and added some mouser codes and was posted back on this forum (the link is the mousered list). As the BOM states CHECKED & UPDATED BY KEVIN - KHStudio on 7-25-07 I had wrongly assumed that this was endorsed by the gurus of NEQ .....which is why all tech docs should be dated.

the bypass cap tip is most appreciated, a little extra work but it'll be worth it.

Quote
Ordering parts is my least favorite thing to do but over the years I've gotten better at it.
Imagine if you had a $35-$50 brokerage fee on top of every order and one always forgets something :evil: oh well (Digikey and Allied excepted thankfully)

I hope this all is helpful to someone else who's in the parts ordering process right now.

Andy
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sysexguy on August 09, 2007, 04:42:00 PM
so Digikey 445-2613-ND looks like the best option (for the bypass caps) at $1.85ea for 25 (stocked and not $5+ea)? any other suggestions?

Andy
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Jed on August 09, 2007, 04:58:55 PM
Folks,

I posted the BOM and as I explained when I posted it, it’s there for review and editing. I’m quite certain there are errors, and now they are being found. I haven’t ordered anything yet and I don’t want to cause someone else any heartache for any mistakes I’ve made.

I’ll try to fix this error later today or tonight when I’ve got some time. I’ll also make some notes on the other posts so that folks know the BOM contains incorrect info.

Apologies,

Jed
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on August 09, 2007, 10:29:32 PM
Jed,
It's OK man. :thumb:
I know your trying to help.

My point is... EVERYONE getting involved in DIY at some point NEEDS to learn about the parts, lead spacings, values, types, etc...

Trust me guys... I was new at this too & still hate it but you will learn & it will go a LONG WAY.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Jed on August 11, 2007, 01:59:20 PM
Baleeted due to request from Kevin.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on August 11, 2007, 03:00:06 PM
Quote

For the .1uf ceramics, I note that Peter suggests polys could be used. There aren't many ceramics at mouser that fit that spot, so I'm looking at this part:
http://www.mouser.com/search/ProductDetail.aspx?R=BQ014D0104J--virtualkey58110000virtualkey581-BQ014D0104J

Would that work?


Heres the data sheet for those.
 Read the APPLICATIONS -
The first 2 on the list are SUPPLY DECOUPLING & FILTERING.
These are 2 things were doing here.
IF THE SPACINGS ARE CORRECT - These will work for almost ALL the caps. :thumb:

1uf, .1, .22, .47

http://www.avxcorp.com/docs/Catalogs/bf-bq.pdf

NOTE: These are like the PANASONIC Stacked Metal films I used from DIGIKEY... 50 OR 63V
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on August 11, 2007, 03:07:50 PM
Quote
I'm also a little shaky on the 47uF/25v lytics. I'm looking at this:
http://www.mouser.com/search/ProductDetail.aspx?R=EKME250ETC470ME11Dvirtualkey66100000virtualkey661-EKME250ETC470ME1

Thoughts? Additional suggestions?


I would use NICHICON PW or KZ series Or Panasonic FC, FM in those spots... including the 470uf spots


I'd stick with ceramic for the 22p (monolithic ceramic, COG or NPO)
VISHAY make them available @ Mouser. They also have .1's :wink:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: louder on August 11, 2007, 03:32:15 PM
Hi
regarding the psu:
or i`m looking at the wrong schm.,or the bom`s you`re showing miss some components,which are:
the two 2k2 resistors at the 317/337 com leg,and two 10uf lytics also at the 317/337 com leg.
these components are needed even if you don`t need the phantom section.
hope i could help.
best regards
pedro
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on August 11, 2007, 04:30:21 PM
Hi Louder

Thanks for spotting that, BOM is updated.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Jed on August 12, 2007, 03:56:41 PM
Also deleted.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Godders on August 12, 2007, 04:38:58 PM
Hi Jed,

I think the terminal block on the PSU should be 3 way (+V, -V & Ground).

Cheers

Nick
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Jed on August 12, 2007, 05:12:44 PM
Yeah, I think you could do it a whole bunch of ways. I was just going to drop in 2 two-way blocks and only use 3 of the slots...

In the off chance that I were to ever re-purpose the power supply I figure you could have easier access to the +48 that way.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Godders on August 14, 2007, 03:35:34 PM
Apologies for the basic question but can someone confirm that I've marked the correct components to leave out if 48v isn't required? I just want to be sure.

Cheers

Nick

(http://img.photobucket.com/albums/v518/godders1/DSC02648.jpg)
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: louder on August 14, 2007, 06:18:02 PM
Hi Nick
that`s correct.
i did mine just like that.
best regards
pedro
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Godders on August 14, 2007, 06:37:58 PM
Thanks Pedro.  :thumb:

Cheers

Nick
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on August 15, 2007, 03:33:36 AM
Godders

Looks good, should be a good guide for those not needing the 48v section.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Godders on August 15, 2007, 04:28:20 AM
Thanks Peter, yes I'll make sure the pic stays.

I think there's a minor error on the PSU BOM; it states 3x 2k2 resistors for 48v operation (2 for no 48v). I see only 2x 2k2 anyway (R1 & R5?).  :?:

Cheers

Nick
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: discobloud on August 18, 2007, 12:05:44 AM
Quote from: "khstudio"
Quote from: "MattiasC"
Is an 18-0-18v toroid acceptable for this or can I get by with a 15-0-15v?


I didn't like the 18v. The regs got VERY HOT.
15v works great & for some reason sounded better... less "Stressed" sounding to me. :?


just wondering ( cause i bought two 18v transformers ) if that "stress" was on a one channel or dual channel eq?  will my eq suffer/not be as good with the 18v?  i got the mouser 41FJ300...

stuffing 4 eq boards and 2 pwr supply boards as we speak.

thanks.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on August 18, 2007, 04:31:42 AM
Quote from: "discobloud"
Quote from: "khstudio"
Quote from: "MattiasC"
Is an 18-0-18v toroid acceptable for this or can I get by with a 15-0-15v?


I didn't like the 18v. The regs got VERY HOT.
15v works great & for some reason sounded better... less "Stressed" sounding to me. :?


just wondering ( cause i bought two 18v transformers ) if that "stress" was on a one channel or dual channel eq?  will my eq suffer/not be as good with the 18v?  i got the mouser 41FJ300...

stuffing 4 eq boards and 2 pwr supply boards as we speak.

thanks.


It was 2 channels.

It may have just been my preference but I built one unit with a 15v & a second with 18v tranny & I didn't like the new one as much... so I hooked it to the 15v tranny & it sounded better to MY ears. I'm not sure if it was regulator "Stress" or not.

It did not such... by NO means. Just use a  good HEATSINK!!!

i ALSO USED toroidals... iS THAT WHAT YOU GOT?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: discobloud on August 18, 2007, 03:24:03 PM
oh hey.  i'm using these http://www.mouser.com/catalog/631/1717.pdf transformers.  as suggested on one of the BOM's floating around.  Should I upgrade to the toroid like this one from digikey TE62053-ND ?  

also i still can't find the pushbutton switch anywheres... i bought the wrong one... again does anyone have a digi key number that works?

thanks

mark
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on August 18, 2007, 03:51:27 PM
Quote from: "discobloud"
oh hey.  i'm using these http://www.mouser.com/catalog/631/1717.pdf transformers.  as suggested on one of the BOM's floating around.  Should I upgrade to the toroid like this one from digikey TE62053-ND ?  

also i still can't find the pushbutton switch anywheres... i bought the wrong one... again does anyone have a digi key number that works?

thanks

mark


OK... That tranny will "WORK"

BUT

I would not recommend it :!:

TOROIDALs are designed to be quieter... Less HUMMMMMMMMMM.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on August 18, 2007, 04:01:35 PM
I have to comment here & mean NO disrespect.

I understand that some of you are trying to be helpful by making "PART LISTS" but if you're new & don't fully understand what your doing PLEASE Don't post a parts list... it will only further confuse others that don't understand.

Resistors are easy
Caps - IC's - Inductors - Switches - POTs have ALL been discussed in this thread.

Quote
digikey TE62053-ND


IS PERFECT  :thumb:
This is what I used.

You SHOULD be fine with 15VA or above
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: discobloud on August 18, 2007, 04:41:49 PM
hey kevin thanks for the info.  didn't mean to 'shine' light on the parts list issue.

i got excited with parts and totally jumped the gun and now have to pay for it...  EQ is the project i've been wanting most.

gonna upgrade and go for the toroids!  

thanks again.

mark
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Jed on August 19, 2007, 03:52:31 PM
Quote from: "discobloud"
didn't mean to 'shine' light on the parts list issue.


Mark, it was me, not you, being overzealous.

I'm gonna ride the pine until I'll get my skills up. Currently I'm more monkey wrench than useful input.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on August 19, 2007, 05:22:28 PM
Quote from: "Jed"
Quote from: "discobloud"
didn't mean to 'shine' light on the parts list issue.


Mark, it was me, not you, being overzealous.

I'm gonna ride the pine until I'll get my skills up. Currently I'm more monkey wrench than useful input.


Is OK man... I know you mean well.
I'm just looking out for everyone. :wink:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: idylldon on August 19, 2007, 08:50:33 PM
Quote from: "discobloud"
also i still can't find the pushbutton switch anywheres... i bought the wrong one... again does anyone have a digi key number that works?

thanks

mark


These should work:

Digikey Part #: 401-1223-ND
ITT Part #: F2UEE

Cheers,
--
Don
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Benny on August 22, 2007, 09:12:42 AM
Just finished the first half of my stereo night eq. Never heard one of those before and I must say I'm impressed...  :grin:  :grin:  :grin:
Just tested it on some vocals, 12strings, drum groups, etc. Really nice.
Especially the Air Band. Smooooooth.
Once again, a big thank you to Kevin and Peter. :thumb:  :guinness:  :sam:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Godders on August 23, 2007, 01:32:44 PM
Another PSU question.

I have polarised electrolytics for the 4 100nf caps but it doesn't say on the pcb which side should be positive? Are MKTs ok here? If not how do I position the 'lytics?

Cheers

Nick
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: louder on August 23, 2007, 03:44:59 PM
Hi Nick
If those are Peter`s psu,they are marked with +(for the lytics).
four 1000 mfd and two10mfd.
for the others caps,i used ceramics,but those mkt will do just fine.
best regards
pedro
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Godders on August 23, 2007, 04:03:58 PM
Thanks Pedro, in the BOM there is a mouser link to some 'lytics for the 0.1uf caps, that confused me a bit. I have some 0.1uf MKT so I'll just use those.

Cheers

Nick
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on August 23, 2007, 04:06:03 PM
Better to use MKT's for the 100nF caps.

I've never seen a low voltage .1uF electrolytic? Do they make such a thing?

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Slenderchap on August 30, 2007, 12:48:47 PM
The 470K rev log Omeg P20 pots with a centre ident (click) are now in stock (part number OM-01-066).

http://www.audiomaintenance.com/acatalog/potentiometers_carbon_20mm_diameter_single_gang.html  (bottom of the page)

 
Colin
www.audiomaintenance.com
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on September 04, 2007, 12:24:30 AM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: okgb on September 04, 2007, 12:39:08 AM
thanks again , Kev
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dissonantstring on September 06, 2007, 01:35:13 PM
thanks for posting those kevin!!
i may do a air-band only build after i finish the dual full band.
has the pcb layout you released a while back (i think it's v.3 or something) been tested?  i really should try it myself and see - but just wondering.

also, just wanted to thank colin for offering the omeg 470K rev. log pots with center detent.  i can't believe how fast they were delivered from the UK to the US (it only took 6 days!! :shock: ).  
not trying to promote anything here, but i ordered some parts for a triangle muff pedal i'm building for a friend from smallbear and ordered it 9 days ago and it still hasn't arrived.  i'm sure the 500K rev. log pots that smallbear is carrying (and has been reported to work well) are great for the price, but  have no fears if ordering the 470K rev. log pots from colin (AML) especially if you want the center detent option.  thanks so much colin!! :thumb:

regards,
grant
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on September 06, 2007, 03:49:45 PM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dissonantstring on September 06, 2007, 04:23:13 PM
cool! :thumb:
thanks so much kevin!
-grant
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: PimD on September 16, 2007, 03:08:17 PM
WOOHOO!!!
Just finished building/testing the EQ, me likey  :green:
Got the pots this week, again a fast one from AML  :thumb:

Unit sounds great, can't wait till i get the purusha case.

Cheers
Pim
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: PD on September 16, 2007, 08:45:05 PM
Pimd, how about some pictures.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: PimD on September 17, 2007, 05:12:34 AM
Will take some when i get a cam, and the case.
Title: true air only?
Post by: nielsk on September 18, 2007, 08:32:54 AM
I am looking to put a "true" air band only (no 2.5k shelf, only the switchable shelf band) into the output of a compressor path. As it is in circuit, I do not need inout or output amps, just single ended. It looks like the input stage (pre cap) can just be deleted, any ideas on the output? Can I just use the U5 block & leave out the U4 block? Or visa versa.....
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: 3nity on October 05, 2007, 11:39:35 PM
trying to find the 100uH inductors at Digikey but without results!! anyone??
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on October 06, 2007, 02:27:27 AM
Quote from: "3nity"
trying to find the 100uH inductors at Digikey but without results!! anyone??


I used these:

Mouser Part #:     542-78F101-RC
Manufacturer Part #:    78F101J-RC
Manufacturer:    J.W. Miller
Description:    Conformal Coated Chokes 100uH 5%
   Page: 818

I think they are available at DIGIKEY also.
Not sure what the difference of a choke & inductor are but they look like what was in my original unit & they are working... also, someone pointed me towards these early on in this project.

Still can't say if they're NEEDED or not. :?
The unit does seem to sound good without them too but I don't have dog hearing :green:
Title: Re: true air only?
Post by: khstudio on October 06, 2007, 02:39:24 AM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: gevermil on October 08, 2007, 09:43:24 PM
So are people using the slenderchap pots or the small bear .
ill bet the dented pot is nice
Im trying to put  my order together and its a pain .
Thanks KHstudio for this and peterc as well .
gary
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Slenderchap on October 09, 2007, 06:56:41 AM
26 people have opted for the centre detent version.... and for the people who have been waiting... they came back into stock yesterday.

Colin
www.audiomaintenance.com
Title: 100uh
Post by: nielsk on October 09, 2007, 08:22:56 AM
The 47.5 R resistor & the 100uH inducter form a zobel, it is there to keep long cable runs from oscillating. I do not see any need for it on a short cable run, but it probably can't hurt.....
I'll keep you posted on reduced versions
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on October 09, 2007, 08:36:43 AM
Not sure the Zobel-name applies here, but indeed, the cap-cable-load is held away from the last opamp for stability-reasons.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: fazeka on November 24, 2007, 03:56:49 PM
I've been reading these Nite EQ threads for a while and maybe I missed something as my eyes are tired...

My V2 boards have two R26: one 20k and one 3k3. Is this a mistake?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on November 24, 2007, 05:19:32 PM
Quote from: "fazeka"
I've been reading these Nite EQ threads for a while and maybe I missed something as my eyes are tired...

My V2 boards have two R26: one 20k and one 3k3. Is this a mistake?



It seems to be a mistake

BUT
                                                                                                                                                                                                                                                                                                          it is labeled correctly on the PCB... so no worries. :green:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: fazeka on November 24, 2007, 07:13:28 PM
Sorry!

Noticed this on Peter's BOM:

"Duplicate R26 - Next to Bypass SW - for LED"
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: louder on November 30, 2007, 06:58:08 PM
Hi
i have two questions before i finish these eq`s:
in the board there`s a hole marked 2-6,that i don`t know where to connect in the rotary sw.i think it goes in one of the inner poles,but i wanna make sure.
second one:for two channels,i`m gonna use a 635ma sb fuse:is it okay?.
sorry for these stupid questions.
best regards
pedro
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on November 30, 2007, 07:30:58 PM
Quote from: "louder"
Hi
i have two questions before i finish these eq`s:
in the board there`s a hole marked 2-6,that i don`t know where to connect in the rotary sw.i think it goes in one of the inner poles,but i wanna make sure.
second one:for two channels,i`m gonna use a 635ma sb fuse:is it okay?.
sorry for these stupid questions.
best regards
pedro


It connects on ALL, 2 THRU 6, on the (a) poll side.
Pin 1 is un-used on BOTH POLLS.

That fuse should be OK... If my math is correct, each card should be drawing less that 100ma.

250 - 300ma TOTAL (LEDs & all) should be enough for a stereo unit.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: louder on December 01, 2007, 12:18:43 PM
Hi Kevin
thank you for the help,and just to make sure:
one side of a wire goes to the hole marked 2-6,the other side goes to the five pins of the sw.
it doesn`t go to the inner pin.
best regards
pedro
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on December 01, 2007, 04:58:34 PM
Pedro

Have a look at this pic:
http://www.groupdiy.com/index.php?topic=19789&postdays=0&postorder=asc&start=450&sid=cb2bbd36507b2873337349e8c10c952f

Fisrt half of the rotary switch:
The hole marked 'a' goes to the inner pin of a 2 x 6way rotary. The hole marked '2-6' goes to the pins 2-6 (joined on the switch). Shown by the 2 white wires in this pic.

The second half of the rotary:
The hole marked 'b' goes to the other inner pin of the rotary. The individual wires marked 2 to 6 go to pins 2-6 on the switch. Shown by the coloured wires in the pic.

Peter
Title: air only
Post by: nielsk on December 01, 2007, 05:42:40 PM
when you say "REMEMBER:
I set up the AIR SHELVES - PARALLEL to a FULL bandwidth signal"
do you mean that the output of the air band (U1A) and the output of the "to all Q's" tie together at the "EQ Sum" point (adding the eq'd signal to the input signal)?

Niels
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on December 01, 2007, 06:39:22 PM
x
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: louder on December 03, 2007, 05:25:36 PM
Hi
it`s alive and well,and noise free,and as for the sound,after a quick listening,sounds very good.
tell you all after serious listening.
thank you all that made this happen.
best regards
pedro
Title: I hope this isn't too much to ask
Post by: funkdrmr on December 27, 2007, 03:24:39 AM
Could anyone verify that I have the correct capacitors sourced on the BOM link below?

Link:  http://www.satellitegrey.com/diy/night_eq/night_eq_caps.xls

*****THIS IS NOT VERIFIED!!!****PLEASE DO NOT USE AT THIS TIME AS A VERIFIED BOM!!! *****

(sorry...but I saw all the problems earlier in the thread when BOM's were posted!)

This is the first time I've had to source capacitors (first project, really!)...and I get a little confused with the different varieties available on Mouser's site.

I think I've gotten close, but I'd really appreciate if someone could verify for me.  I've put the mouser links in Column "L" on the row of their respective part, so you should be able to click the links & check real quick!

I've been reading this thread for about 5 hours now and it's helped a ton...I'd just really appreciate a second-check from anyone more experienced than I am (read....ANYONE else!)
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Godders on December 27, 2007, 01:58:40 PM
Link doesn't work for me.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: funkdrmr on December 27, 2007, 05:32:43 PM
Sorry about that...fixed the link!
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Godders on December 27, 2007, 07:40:07 PM
Those 22pf ceramic caps are SMD (surface mount) so are the wrong type. You want something like p/n 81-RPE5C1H220J1A1Y02.

The boxed metal films and nichicon lytics should be fine, up to you to make sure the lead spacings and values are OK though!

Cheers

Nick
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: funkdrmr on December 27, 2007, 09:02:38 PM
Thanks for the help, Nick!

The lead spacings is one of the harder things I had to search for.  I'm sure I didn't get it correct.

Thanks for letting me know I'm on the right track!
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: laiben on December 28, 2007, 09:13:22 PM
funkdrmr, the 470uf/63v capacitor maybe too big for the pcb, also as I remember the spacing of that capacitor is 5mm on the pcb. Pls measure it again.

laiben
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: funkdrmr on December 28, 2007, 09:56:20 PM
Thanks, laiben!

I've gotten together with Jed, so I'm using his "mouser" list along with the information I have.

Everything looks good so far.  I'm hoping it can be verified by someone here before I order but if not, I think it's close enough to order anyways and figure it out from there.

I'm hoping it will be something that can be shared & used by everyone else to make things easier.  Sourcing the parts seems to be such a difficult task when you're new at this stuff and I'd love to be able to give SOMETHING back for this project.

I appreciate all the help so far.....I'm sure I'll have more questions this weekend!
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: laiben on December 31, 2007, 10:12:18 AM
Here are my boards working in progress. The PSU board is the green preamp PSU board from peter.

The 470uf/63v cap is too tall for 1U rack!! I have to order some Panasonic cap from Farnell to replace them.

(http://i4.photobucket.com/albums/y136/laiben/DIY%20Night%20EQ/RIMG1616.jpg)

(http://i4.photobucket.com/albums/y136/laiben/DIY%20Night%20EQ/RIMG1620.jpg)

(http://i4.photobucket.com/albums/y136/laiben/DIY%20Night%20EQ/RIMG1621.jpg)

laiben
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on December 31, 2007, 02:16:07 PM
Looks good but damn those caps are BIG  :shock: .

 :green:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: funkdrmr on December 31, 2007, 03:05:09 PM
I found a small store here on Oahu that has nearly everything I need for this project!  They even have the resistors / caps separated and labeled, but not by brand name.

The 470uf/63v caps I found there are CONSIDERABLY shorter than what you have on your boards.  I can't tell what brand they are, though.

Is there any color scheme for the caps that I can use to tell what brand they are?  Maybe abreviations of the company name on the caps themselves?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: laiben on December 31, 2007, 06:29:46 PM
Those 'audiophile' caps (nichicon KZ muse, elna) are always oversized. :evil:

Next time I would rather get the Panasonic cap from Farnell if they are available.

laiben
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: funkdrmr on January 01, 2008, 01:39:08 AM
Sorry for the noob question here, everyone, but I've GOTTA ask.

I just got done stuffing all of the resistors, but noticed something I'm unsure about.

On the PCB there are some 22R resistor spots labeled RPSU.

I'm assuming 22ohm resistors go there....also, could someone tell me what RPSU stands for, or what these do in the circuit?

Thanks and Happy New Year!
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on January 01, 2008, 07:43:36 AM
I use RPSU to indicate a resistor from a power rail to the supply pin (usually on an opamp). It isolates the opamp from the supply line, in conjunction with a cap, usually labelled CPSU

They are usually 22R or so in value.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dagoose on January 01, 2008, 04:01:19 PM
My Nite EQ is up and running! well... i tested it and it works great! Now i need to order my frontpanel at schaeffer and it can be racked up :)
It sounds really sweet, i love the air section on 40khz, it freshens up the sound without getting harsh. Just did some quick tests but so far i'm really happy with the result, no hum, noise or what ever, just sweet EQ'ing.
Here is what mine looks like from the inside right now.
(http://www.dagoosemusic.nl/diy/nite/6.jpg)
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: funkdrmr on January 02, 2008, 03:53:24 AM
I'm getting stoked seeing everyone's progress.  I just stuffed all of the resistors yesterday & today and I think it's going ok for a first-timer!

No pics yet, but I do have another question.

My local parts store has both the 5532 and 5534 IC's in stock so I'd really like to purchase them there if I can.

HOWEVER....I'm unsure of the brand name at this time (going back tomorrow).  

Is there a preference, or a difference between T.I., ON Semiconductor, Fairchild 5532's and 5534's or is this a case that as long as it's a "5534 IC", it will be good to go?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: fazeka on January 02, 2008, 04:16:33 AM
Quote from: "funkdrmr"
My local parts store has both the 5532 and 5534 IC's in stock so I'd really like to purchase them there if I can.


IC Supply? Honolulu Electronics? Precision Radio?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: funkdrmr on January 02, 2008, 05:49:17 AM
IC Supply.

I couldn't find Honolulu Electronics, and didn't know Precision Radio existed and carried the type of stuff we can use.

Are you out here, fazeka?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Samuel Groner on January 02, 2008, 06:44:59 AM
Quote
The 470 uF/63 V cap is too tall for 1 U rack!

Which cap is this? Why does it need to be rated for 63 V?

Samuel
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: funkdrmr on January 02, 2008, 07:07:18 AM
Someone correct me if I'm wrong, but it looks like this cap is for C1, C14, and C15.  63v is specified for protection in case it's exposed to Phantom Power.

Hope that helps....I'm not sure what it does in the circuit, if that's the info you're after.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Samuel Groner on January 02, 2008, 09:39:05 AM
Quote
It looks like this cap is for C1, C14 and C15.

Indeed it does.

Quote
63 V is specified for protection in case it's exposed to phantom power.

Clever idea, but not well thought trough. C1 never sees mor than 18 V as U4 won't swing any higher than the rails. C14 and C15 won't see anything more than ~29 V due to R28 and R33 forming a voltage divider together with the phantom power resistors.

So: these caps can be 35 V (C1 even 25 V), which makes them substantially smaller and easy to fit in 1 U.

Samuel
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 02, 2008, 04:50:10 PM
NOTE:

Cin1 & Cin2 (labeled on PCB) were added for phantom protection by Peter.
The originals didn't have them.
I didn't load them in mine... just jumped them.

#2
I'm not sure how C14 & C15 got so large a voltage.  :?
The originals are 25v & that is what I used in my units as well.
I will fix this on the schematic... sorry.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 02, 2008, 05:36:52 PM
I Have updated my web site with the current Parts list, Schematic & Overlay

http://www.khstudio.us/DIY.htm

Just click on Nite EQ  :wink:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: funkdrmr on January 02, 2008, 06:01:07 PM
Thanks, Kevin!

Can you provide some insight on my NE5532 / NE5534 question above?  It seems my local store has the Fairchild model of these IC's in stock so I would like to pick them up.

I'm worried that there is a difference or preference between different brands like Texas Instruments, ON Semiconductor, Fairchild, etc...

Thanks again for all for this project.  It's my first one and I'm having a BLAST sourcing and soldering everything up.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 02, 2008, 06:16:08 PM
Quote from: "funkdrmr"
Thanks, Kevin!

Can you provide some insight on my NE5532 / NE5534 question above?  It seems my local store has the Fairchild model of these IC's in stock so I would like to pick them up.

I'm worried that there is a difference or preference between different brands like Texas Instruments, ON Semiconductor, Fairchild, etc...

Thanks again for all for this project.  It's my first one and I'm having a BLAST sourcing and soldering everything up.


ANY of the RIGHT "TYPE = 5532 or 5534, will work fine.

The original used JRC 5532D & Signetics NE5534AN.

I happen to like the JRC's... there cheap & available.

BUT, I would have NO problem using others like the TI's.

If you read back earlier in the thread I get into the IC discussion & preference in more detail.  :wink:

Good Luck  :thumb:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: funkdrmr on January 02, 2008, 06:40:05 PM
HAHA...I was JUST reading those posts when you replied.

Thanks!  I think I'm just gonna stick with the components you used.  I hope DigiKey shipping is fast!
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bluezplaya on January 05, 2008, 01:18:18 PM
I have a question regarding the pushbutton switch and the 500k pots. Are there any substitutes for these at Mouser or Digikey?

Adam
Title: Switch
Post by: funkdrmr on January 09, 2008, 07:14:18 AM
For the switch, I'm using P/N: 401-1223-ND from Digikey.
Title: Power Supply Questions
Post by: funkdrmr on January 09, 2008, 07:25:19 AM
I have everything pretty much stuffed except for the power supply.

I have a few questions about the P/S from Peter, so hopefully someone can help me out!

(http://www.satellitegrey.com/diy/peter_psu.jpg)

I think I ordered some incorrect caps, and I'm unsure about the value of some parts.

1.  For the 1000uF caps in the middle, are 1000uF/10v too small of voltage?

2.  For the 10uF cap in the lower right corner, is it okay to be 63v or does it need to be 35v?

3.  For the rest of the places marked in red, the writing on my board isn't clear.  Could someone let me know what values go in those slots?

4.  Are heat sinks a requirement for LM317 and LM337?

Thanks again for any help!
Title: Re: Power Supply Questions
Post by: radiance on January 09, 2008, 07:34:41 AM
Quote from: "funkdrmr"

I think I ordered some incorrect caps, and I'm unsure about the value of some parts.

1.  For the 1000uF caps in the middle, are 1000uF/10v too small of voltage?

2.  For the 10uF cap in the lower right corner, is it okay to be 63v or does it need to be 35v?

3.  For the rest of the places marked in red, the writing on my board isn't clear.  Could someone let me know what values go in those slots?

4.  Are heat sinks a requirement for LM317 and LM337?

Thanks again for any help!


1) should be 25V or higher. This is a 2 X 15V (or 2 X 18V) psu right?
2) in PSU's higher voltage is no prob, so yes...63V is ok.
3) I think they should be 100nF  (0,1uF)
4) running cool means longer life....
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on January 09, 2008, 10:05:38 AM
As Radiance sed.....

Thx

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: funkdrmr on January 09, 2008, 02:31:27 PM
Thanks Radiance & Peter....much appreciated!
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: funkdrmr on January 13, 2008, 08:36:40 PM
Some pics!

Sorry if they're grainy....my phone camera is all I've got right now.

(http://www.satellitegrey.com/diy/night_eq/main.jpg)

(http://www.satellitegrey.com/diy/night_eq/power_supply.jpg)

And of course....a QUESTION!

In the next pic, you can see one of the voltage regulator heat sink BARELY touching the 1000uF capacitor on the power supply board.

(http://www.satellitegrey.com/diy/night_eq/ps_heat.jpg)

Is this ok?  Do I need to bend the heat sink out a little bit to fix this?

Just waiting on the pots from the UK now and I can fire this thing up!
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on January 14, 2008, 12:54:16 AM
Funk

Check to see if the reg gets hot, if it does then either put a heatsink onto it or bend it away from the cap.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: CJ on January 14, 2008, 02:49:55 AM
Peter, I need some C, can you help[ me?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on January 14, 2008, 03:19:25 AM
:grin:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bluezplaya on January 14, 2008, 09:46:45 PM
I am stuffing the resistors on my boards righ tnow and was wondering about the *optional* 22R resistors. Can anyone explain what the options are?

Thanks,
Adam
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on January 15, 2008, 12:34:39 AM
Optional 22R?

I think the ones you are referring to are the ones that decouple the opamps from each other. You could leave them out without much difference, I think, although I have always had them in mine.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: jdbakker on January 15, 2008, 03:34:42 AM
...and by 'leave them out' I suspect Peter means 'short them out / replace them with a wire bridge'. These resistors are in series with the opamps' supply lines; if you just leave them open the circuit won't work.

JD 'correct me if I'm wrong' B.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on January 15, 2008, 03:48:16 AM
Quote
...and by 'leave them out' I suspect Peter means 'short them out / replace them with a wire bridge'.


Ooops :oops:

JD is correct.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on January 15, 2008, 03:48:40 AM
Quote
...and by 'leave them out' I suspect Peter means 'short them out / replace them with a wire bridge'.


Ooops :oops:

JD is correct. Thx JD
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 15, 2008, 04:11:22 AM
Quote from: "bluezplaya"
I am stuffing the resistors on my boards righ tnow and was wondering about the *optional* 22R resistors. Can anyone explain what the options are?

Thanks,
Adam



optional = means use or don't use.

The 22R resistors you're referring to are for the input of the POWER RAILs - \
They weren't in the Original Unit BUT are fine to install & are probably a good idea.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 15, 2008, 04:12:46 AM
Quote from: "peterc"
Quote
...and by 'leave them out' I suspect Peter means 'short them out / replace them with a wire bridge'.


Ooops :oops:

JD is correct. Thx JD


YES, this is correct.
If you leave them out you won't get any power to the board. :wink:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bluezplaya on January 15, 2008, 08:16:12 AM
:thumb:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bluezplaya on January 15, 2008, 12:43:51 PM
I am using Panasonics on these boards and I get to the 470uf/63v caps and they are too big for the solder holes. They are Panasonic FC's. Does anyone know another series of Panasonic that would have smaller caps of this value? I'm wanting to keep this build to 1U space rack.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 15, 2008, 01:10:09 PM
Those (3) 470uf caps DO NOT NEED to be 63v...

25v is fine.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bluezplaya on January 15, 2008, 04:18:12 PM
Does anyone have a P/N on the 100uH inductor? If not a P/N, a brand?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 15, 2008, 04:41:24 PM
Quote from: "bluezplaya"
Does anyone have a P/N on the 100uH inductor? If not a P/N, a brand?


Mouser:

J.W.Miller Conformal Coated Chokes
100uH 5%

P/N: 542-78F101-RC

If they don't have these in stock you can get the same thing in a slightly smaller or larger size (I forget which one) both will work & I've used both.
Just make sure it's 100uH :!:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bluezplaya on January 15, 2008, 05:08:50 PM
And one more thing I SWEAR  :roll:  what is the part number for the DPDT switch?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: funkdrmr on January 15, 2008, 06:06:56 PM
Quote from: "bluezplaya"
And one more thing I SWEAR  :roll:  what is the part number for the DPDT switch?


Here's the digikey p/n that I ordered.  I think Kevin provided it earlier in this thread as well.

401-1223-ND
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Neeno on January 16, 2008, 05:04:40 AM
Hi Guys !
I just received a dozen pots from Colin (thank you).
I have to say that the rotation feel is better than the pots I've got from Omeg before.

Yesterday i measured the resistance in the middle position of the small batch that i've got, 11 of them are around 54-57k but one is out of the ball-park and it measures 70k  :roll:

How can i proceed ?
Anyone knows how can I modify the circuit to get a Gain of 1 having 70k in the middle position of the pot ?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on January 16, 2008, 08:40:45 AM
Hi Neeno,

if you don't simply want to displace the knobmarker, have a look at  this Excel sheet  (http://www.hausverwaltung-heger.de/al_leck_trick/3D-EQ_PotTweaking.xls).

-Harpo
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Neeno on January 16, 2008, 09:07:42 AM
Thank you Harpo !
I've got those pots from Colin, displacing the knob would not be a problem but since they are center detented i'll try to tweak the ciruit...
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: laiben on January 31, 2008, 11:45:21 AM
my pots are the same... they are close to 60K instead of 47K..
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 31, 2008, 03:24:47 PM
Quote from: "Neeno"
Hi Guys !
I just received a dozen pots from Colin (thank you).
I have to say that the rotation feel is better than the pots I've got from Omeg before.

Yesterday i measured the resistance in the middle position of the small batch that i've got, 11 of them are around 54-57k but one is out of the ball-park and it measures 70k  :roll:

How can i proceed ?
Anyone knows how can I modify the circuit to get a Gain of 1 having 70k in the middle position of the pot ?


If your getting 54-57k, I'd say you're in good shape.
If you read back a little, HARPO mentions the Calculated (not exactly the original - which mine measured around 47-48k average) center point, the circuit SHOULD be... I think it's around 50k-51k.
I also think Peter said this to me in an email WAY back.
So, you can adjust your 5.6k resistors & be in very good shape.  :wink:

I'd say a CENTER POINT anywhere around 48k - 52k would be good.:idea:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: laiben on January 31, 2008, 10:02:08 PM
Quote from: "khstudio"
Quote from: "Neeno"
Hi Guys !
I just received a dozen pots from Colin (thank you).
I have to say that the rotation feel is better than the pots I've got from Omeg before.

Yesterday i measured the resistance in the middle position of the small batch that i've got, 11 of them are around 54-57k but one is out of the ball-park and it measures 70k  :roll:

How can i proceed ?
Anyone knows how can I modify the circuit to get a Gain of 1 having 70k in the middle position of the pot ?


If your getting 54-57k, I'd say you're in good shape.
If you read back a little, HARPO mentions the Calculated (not exactly the original - which mine measured around 47-48k average) center point, the circuit SHOULD be... I think it's around 50k-51k.
I also think Peter said this to me in an email WAY back.
So, you can adjust your 5.6k resistors & be in very good shape.  :wink:

I'd say a CENTER POINT anywhere around 48k - 52k would be good.:idea:


so if the center point is 60K, even the 5.6k resistor is removed, it is still too much resistance? is the difference audible?

 :roll:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on January 31, 2008, 10:37:38 PM
#1
I'm not so sure you can or SHOULD completely remove the 5.6k...
I'd at least put something low in there...10 or 12 ohms maybe.
Someone else with have to give you more technical reasons.

Not being fully centered will just give you a hair more (or less) volume at Center, compared to Bypassed... I wouldn't call it a big deal & IT WILL NOT effect the "sound" of the EQ AT ALL.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Sorr on February 01, 2008, 12:33:30 AM
Has anyone experimented with different EQ capacitors?
Any preferences?

Sorr
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MrZpliff on February 01, 2008, 02:46:55 AM
Quote from: "khstudio"
#1
I'm not so sure you can or SHOULD completely remove the 5.6k...
I'd at least put something low in there...10 or 12 ohms maybe.
Someone else with have to give you more technical reasons.

Not being fully centered will just give you a hair more (or less) volume at Center, compared to Bypassed... I wouldn't call it a big deal & IT WILL NOT effect the "sound" of the EQ AT ALL.


I've bypassed the resistors on some of my pots. Seem to work fine, though I've only tested it for about half an hour. Haven't had the time to rack it up yet  :sad:
There might be some reason not to bypass them completely though. But that's a little above my head  :?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on February 01, 2008, 06:44:31 AM
Hi MrZspliff,

you shurely have seen   this Excel sheet  (http://www.hausverwaltung-heger.de/al_leck_trick/3D-EQ_PotTweaking.xls) ?

This Resistor is Part of R in and sets the max.gain of this inverting summing stage, varying between -20dB to +20dB. Voltage gain -AV=56k2/(R potentiometer + 5k62) = R30 / (R42 + R43) for the 40Hz band, ... or R30 / (R38 + 39) for the 650Hz band. If you bypass this series resistor, you'll overload this summing stage, as the max.gain setting try to reach infinity, only limited by rail voltages.

-Harpo
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MrZpliff on February 01, 2008, 06:56:04 AM
Thank's for the information.  :thumb:
Is that a problem in reality ? I doubt I'll ever cut or boost more than about 5 dB with this EQ. Probably no mare than a few dB's...  :?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on February 01, 2008, 07:09:37 AM
Quote from: "MrZpliff"
Thank's for the information.  :thumb:
Is that a problem in reality ? I doubt I'll ever cut or boost more than about 5 dB with this EQ. Probably no mare than a few dB's...  :?

Might get a problem when boosted accidently by whoever else dials your potentiometers.
If all pots have nearly the same value at center, simply change the feedback resistor R30 to the resistor value at center ie. 65k or whatever yours have + the series resistor 5k62), giving 70k62 for previous example and change the resistor R48 for bypass to this same value.
-Harpo
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MrZpliff on February 01, 2008, 07:44:02 AM
Quote from: "Harpo"
Quote from: "MrZpliff"
Thank's for the information.  :thumb:
Is that a problem in reality ? I doubt I'll ever cut or boost more than about 5 dB with this EQ. Probably no mare than a few dB's...  :?

Might get a problem when boosted accidently by whoever else dials your potentiometers.
If all pots have nearly the same value at center, simply change the feedback resistor R30 to the resistor value at center ie. 65k or whatever yours have + the series resistor 5k62), giving 70k62 for previous example and change the resistor R48 for bypass to this same value.
-Harpo


Thank's again. I think I get it.
Need to check with the schematic.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: idylldon on February 01, 2008, 06:49:13 PM
Anyone using Peter's power supply board with the NightEQ?  Should I use an 18-0-18 transformer or a 15-0-15?  I know someone mentioned that running the 18 volt tranny made the regs run pretty hot.

Thanks,
--
Don
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on February 01, 2008, 07:13:33 PM
Quote from: "idylldon"
Anyone using Peter's power supply board with the NightEQ?  Should I use an 18-0-18 transformer or a 15-0-15?  I know someone mentioned that running the 18 volt tranny made the regs run pretty hot.

Thanks,
--
Don


I tried to use an 18v-0-18v tranny in mine & it DID make the regs hot.... not to mention it made the EQ "Sound" different... & not in a good way.
I used a 15-0-15 instead & it worked GREAT & even sounded better to my ears (+ my friend & the guy I was building it for)... go figure. :?

15v trannys look a little higher when unloaded (how much depends on how big or much current the tranny has to offer)
But 15v X 1.4v (diode Rectifier) you get = 21volts
Even loaded down a little this has worked well for me & should be fine to get a Regulated 18v DC!
If your worried, just knock your DC down a little... like 17v & you'll be fine.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: idylldon on February 02, 2008, 11:03:25 PM
Thanks, Kevin.  I'll go with a 15-0-15.

Cheers,
--
Don
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Grooveteer on February 05, 2008, 10:27:42 AM
I have so much to learn...  :oops:

I'm done stuffing the boards, and I must have done somehing wrong here. Both units pass audio but al a very low volume and it sounds as if I'm going trough a low-pass filter. Really boomy.  The EQ does work; but is unusable because of the issues above.  I'm a real noob at this, does anyone have a clue on where to start looking?  Could it be the wiring of the Lorlin?

Thanks so much.

Cheers,

G
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dagoose on February 05, 2008, 11:11:48 AM
Quote from: "Grooveteer"
I have so much to learn...  :oops:

I'm done stuffing the boards, and I must have done somehing wrong here. Both units pass audio but al a very low volume and it sounds as if I'm going trough a low-pass filter. Really boomy.  The EQ does work; but is unusable because of the issues above.  I'm a real noob at this, does anyone have a clue on where to start looking?  Could it be the wiring of the Lorlin?

Thanks so much.

Cheers,

G


Have you checked the balnced/unbalanced jumper together with the balnced/unbalbced connection? I had the same problem at first, distorted when i added a couple of DB of eq boost and very boomy and soft.
If you have the jumpers in for balnced, connect it balanced
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on February 05, 2008, 11:31:06 AM
Quote from: "Grooveteer"
Both units pass audio but al a very low volume and it sounds as if I'm going trough a low-pass filter. ... Could it be the wiring of the Lorlin?

Hi Grooveteer,

miswiring of the lorlin is unlikly, as this "air" stage is only adding.

Turn the unit to bypass and check, if volume loss and the boomy sound remains. If so, the error resulting in boom sound is probably the tiny c13 cap across the feedback resistor R30 of the summing amp U5. Should be 22pF, not nF or uF. Loss in gain when bypassed is probably caused by a wrong resistor value. Check correct value of R1,2,3,4,26,27,30,31,47,48.

Case the unit bypassed is ok, check correct values of the caps between op-amps inverting input and their output, each value labled .1uF (=100nF). If you missed the decimal dot in front of the 1, the according lpf cutoff frequency will be 10 times lower than its hpf cutoff point in the same amp stage, resulting in boomy sound and about 15dB loss in gain.

-Harpo
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Grooveteer on February 06, 2008, 02:00:25 PM
Harpo: You mean that 0.22 uF cap that I had there?  :oops:    Problem solved. Thanks man!  :guinness:

To add further to my shame: Da Goose was right too. I forgot the jumpers for balanced / unbalanced.  Made no difference though. (still had the wrong cap at C13, maybe that's why I could't hear the difference)

Need to do some more listening, but so far I like what I'm hearing.

Cheers,

G (Happy, happy camper)
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: ilikeit on February 06, 2008, 02:57:10 PM
hi
me too i have started a nite eq but i have a little problem
i don't know how to link the rotary switch for the AIR frequency
q 5-6 B 1 2 3 4 5 6
???
can you help please!
thanks a lot
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on February 06, 2008, 06:45:01 PM
Quote from: "ilikeit"
hi
me too i have started a nite eq but i have a little problem
i don't know how to link the rotary switch for the AIR frequency
q 5-6 B 1 2 3 4 5 6
???
can you help please!
thanks a lot

Hi ilikeit,
have a look at the schematic.  :wink:
The Lorlin switch is a 2 pole (center terminal A+B), 6 position (1-6 for pole A, 7-12 for pole B) switch. If you're not shure because of other brand or different labeling, just ohm it out.
Lorlin center terminal 'A' connects to PCB 'Q', leading to op-amp pin 1, outer Lorlin terminals 2,3,4,5,6 of section 'A' are all joined and connect to PCB '2-6', leading to the potentiometer R34, terminal 1 is not connected (for off position).
Lorlin center terminal 'B' connects to PCB 'B', leading to R6 and outer Lorlin terminals 2,3,4,5,6 of section 'B' lead to the according '2', '3',...,'6', leading to the frequency setting caps. Again terminal '1' is not connected (for off position).
This is shurely (and probably better) explained in a previous post.
-Harpo
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: ilikeit on February 19, 2008, 01:51:11 AM
hello,
I began the manufacture of my nite eq before putting my cheap I wanted to test the power I have definitely + /-18V but all my 22 ohm resistence smokes
 somebody has  had this probleme?
 however after examination my PCB is clean
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on February 19, 2008, 02:24:18 AM
Quote from: "ilikeit"
hello,
I began the manufacture of my nite eq before putting my cheap I wanted to test the power I have definitely + /-18V but all my 22 ohm resistence smokes
 somebody has  had this probleme?
 however after examination my PCB is clean


You definitely have something wrong!!!
The board works.

carefully recheck everything until you find it.
You could also post some DETAILED Pictures so we can see what's going on.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on February 19, 2008, 05:19:23 AM
If all the 22R resistors are smoking, it sounds like a dead short across the supply rails.

Disconnect the PSU & measure the resistance from the + rail to ground & the - rail to ground.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: ilikeit on February 19, 2008, 02:15:03 PM
it s very strange...
all my resistor make 22 ohm
when I weld them on PCB, they make no more than 18 ohm
but it parried normal
when I welded all my RPSU and that I measure I acquire 32 ohm between +18 and - 18V (I took away feeding)however I have definitely look and all my soldering is clean
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on February 19, 2008, 07:17:57 PM
Quote from: "ilikeit"
it s very strange...
all my resistor make 22 ohm
when I weld them on PCB, they make no more than 18 ohm
but it parried normal
when I welded all my RPSU and that I measure I acquire 32 ohm between +18 and - 18V (I took away feeding)however I have definitely look and all my soldering is clean

Hi ilikeit,

as Kevin already posted, a pic could help to narrow it down, so a little flying blind. Anyway, step by step..,
disconnect your supply, pull all your (maybe blown) op-amps, replace the burnt 22R resistors (32R across +/-18V rails would pull 1,125A and require >40 W rated resistors to survive) and measure resistance again between +18V connector and socket pin-8 of the dual op-amps NE5532 as well as pin-7 of the single op-amp NE5534 below the 470uF cap C15. Should read about 22R each. Same to the negative rail between -18V connector and socket pin-4 of NE5532 as well as NE5534. Case not, locate the short following the rail traces.
Between +18V and -18V connector I'd expect a value between 1M and infinity, same between +18V connector and gnd. Between -18V connector and gnd eighter a value above 1M/infinity or about 3k3, depending on position of the bypass-switch, caused by current limiting R for the LED.
Reconnecting your supply and powering up, you should check your +/-18V rail voltages at op-amp sockets pin-4 and pin-7/pin-8. If all seems OK, power down again.
Next step, check if your op-amps survived. Measure resistance between op-amp pins-8/4 for all NE5532's and between pins 7/4 for the NE5534, reading some Mohm. Case not, this op-amp is probably blown, so replace it by a new one.
Hopefully final step will be to put the the op-amps back into their sockets. Take care of the right direction and the different chip in the middle.
-Harpo
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: ilikeit on February 21, 2008, 06:12:37 AM
hi Harpo and thanks for you answer
i re checked my PCB
i have 19ohm between the +18V rail and the pin of different NE
it's identical between the -18V and the other pin
i have checked too my cheap
everything is ok
but i have always 32ohm between the + and the - 18v
i don't want plug the PSU before looking for the probleme
all idea are welcome
regards
greg
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on February 21, 2008, 06:44:53 AM
Take out the opamps, & measure the resistance between pins 8 & 4 on the 5532 & pins 4 & 7 on the 5534. They should be open cct or high resistance. Measure between 8 & gnd, 7 & gnd & 4 & gnd on the various opamps, should be fairly high resistance, above 15k or so.


Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: discobloud on February 27, 2008, 08:57:22 PM
Quote from: "ilikeit"
hello,
I began the manufacture of my nite eq before putting my cheap I wanted to test the power I have definitely + /-18V but all my 22 ohm resistence smokes
 somebody has  had this probleme?
 however after examination my PCB is clean


I'm having a similar problem.  I built 4 channels(2 units) and used a 15-0-15 tranny with Peter PSU and one of the channels burns the 22R resistors.  The board is clean and not sure what do to.  I changed the resistors, rechecked all the connections and it burnt them again.  

I'll take some photos later.  Is there something I should be looking to change/replace, the other channel didn't burn.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on February 28, 2008, 01:19:14 AM
Disco

Do the resistors burn when the IC's are taken out?

Take the IC's out of both of the channels & then do some DC voltage checking on the pins of the opamp sockets.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: ilikeit on February 28, 2008, 03:07:49 AM
hi
peterc has right
i checked  all my IC with a metrix
everything was alright
but when i placed it on the PCB i haved  22 ohm between the pin of PSU
i place one  after one the IC on the PCB and each time  i have checked my metrix
and i find one IC was dead
now my nite eq is good!!
 :grin:

(sorry for my english :oops: )
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: discobloud on February 29, 2008, 03:51:31 PM
I figured it out.  Thanks so much for the help.  I'll post photos of the finished builds later.

[edit later that eve]

(http://img444.imageshack.us/img444/5228/img3912bg4.th.jpg) (http://img444.imageshack.us/my.php?image=img3912bg4.jpg)

(http://img168.imageshack.us/img168/2356/img3915uw7.th.jpg) (http://img168.imageshack.us/my.php?image=img3915uw7.jpg)

thanks to Kevin, PeterC, Purusha and everyone else involved.  Great sounding EQ.  

is this the same EQ http://electrical.com/item.php?page=5&pic=pictures/5-0.jpg

nice description

mark
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: ChuckD on March 03, 2008, 03:54:56 AM
Here's my latest build. Did it as a favor for a producer friend here in LA. He's helping me with my latest record.


(http://www.pillarsofnein.com/diy_projects/Night_EQ/Photos/chuck_3dEQ1.jpg)
(http://www.pillarsofnein.com/diy_projects/Night_EQ/Photos/chuck_3dEQ2.jpg)
(http://www.pillarsofnein.com/diy_projects/Night_EQ/Photos/chuck_3dEQ3.jpg)
(http://www.pillarsofnein.com/diy_projects/Night_EQ/Photos/chuck_3dEQ4.jpg)


I squeezed it into an old Alessis box and used parts laying around. Probably the cheapest build ever!

Not a bad EQ at all. The Air is a really cool set of bands

-ChuckD
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: discobloud on April 04, 2008, 03:41:29 PM
I'm having s small problem with one of the channels.

When I turn up the SUB pot to about 1 o'clock, the channel distorts and if i keep turning the EQ, the signal vanishes.  I changed all the op amps and changed the pot in question too.  Not sure what else I should be looking for.  The board is clean and I checked all the solder joints too.

Also when I put it in bypass, then switch it back, it takes a 1/4 second to kick in.

photo of the build
http://img444.imageshack.us/img444/5228/img3912bg4.jpg

Thanks

Mark
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: vertiges on April 05, 2008, 01:23:13 PM
dicobloud & ChuckD, nice work guys !!  :thumb:

I have to finish mine, I have to finish mine !!!  :green:

ed)))
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: matta on April 22, 2008, 06:01:58 AM
Hi Guys,

I'm trying to wrap up a Night EQ build and have a couple questions. Obviously I'm aware that the pots need to be tailored to the circuit esp. if they are center deteneted and I have Harpo's GREAT spreadsheet (thanks again, you are spreadsheet king!).

The first board is done and it seems on paper to work well (not tried it in practice), sadly though on the 2nd channel one pot measures 470K but the center is pretty high at 79.1K!!!

Here are my pot values and center points

Sub = R45 = 472K = 60.31K
40 Hz = R43 = 489K = 58.83K      
160 Hz = R41 = 441K = 56.35K   
640 Hz = R37 = 470K = 79.10K   
2.56 kHz  = R37   = 442K = 57.73K

Punching the numbers into the spread sheet I get the following results.

Sub = R45 = 26,700K
40 Hz = R43 = 28,180K      
160 Hz = R41 = 30,660K      
640 Hz = R37 = 7,910K      
2.56 kHz  = R37   = 29,280K      

Replace R30 and R48 with 87,010

Does that look right? So all my once 5K62's now jump to over 25K?

Also I notice the spreadsheet doesn't cater for the the 'AIR' band? What is done here with the series resistors RE trying to center the gain pot? Does it not effect the rest of the bands like the others do, for in the case of the above example it seems that any change in the center point will effect the resistors around them?

Thanks in advance!!!!

Matt
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on April 22, 2008, 07:21:30 AM
Hi Matt,

your numbers seem right, but I don't think you'll get lucky with your 79k1 pot at center for 640Hz, resulting in about 10dB less boost for the remaining bands. (if you can't exchange it with another pot, a 330k in parallel to this pot might be a better compromise, so value of this pot/rheostat at center would be 63k8 for 193k9 total resistance).
The air band is only adding (no -dB), so a center detented pot doesn't make much sense in this place, though it won't hurt. You may try to exchange this pot as a replacement for your 640Hz band pot.
-Harpo
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: matta on April 22, 2008, 10:06:41 AM
Thanks Harpo,

As always, you rock! You know I didn't even spot the AIR band was only ADDITIVE... pays to look doesn't it! Well I'll prob do just that swap out one of the remaining 2 pots I have for the 640hz and use the 79K1 for the 'AIR' band.

Thanks again!

Matt
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: laiben on May 03, 2008, 10:54:46 AM
Hi,

I just got one of the channel of my Night EQ completed and it doesn't work!

The voltage on the IC socket is okay (I use +/- 15V) but some how it only produce very weak sound in bypass mode and have no sound at all when the EQ is switched in. I would like to verify the signal path but I found that the schematic by kevin (Thanks for the hard work!) is only part of the circult on Peterc's PCB (Thanks for the pcb work too!).

Is there any full schematic of the PCB including the PSU parts and some bypass caps?

Thanks
laiben
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on May 04, 2008, 01:31:24 AM
Quote from: "laiben"
Hi,

I just got one of the channel of my Night EQ completed and it doesn't work!

The voltage on the IC socket is okay (I use +/- 15V) but some how it only produce very weak sound in bypass mode and have no sound at all when the EQ is switched in. I would like to verify the signal path but I found that the schematic by kevin (Thanks for the hard work!) is only part of the circult on Peterc's PCB (Thanks for the pcb work too!).

Is there any full schematic of the PCB including the PSU parts and some bypass caps?

Thanks
laiben


Post a link to some "Close up" pics & I'll take a look.

I've built a few of these with no problems.
The Schematic really isn't missing much at all.

Did you install the jumpers???
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: laiben on May 04, 2008, 12:05:30 PM
Quote from: "khstudio"
Quote from: "laiben"
Hi,

I just got one of the channel of my Night EQ completed and it doesn't work!

The voltage on the IC socket is okay (I use +/- 15V) but some how it only produce very weak sound in bypass mode and have no sound at all when the EQ is switched in. I would like to verify the signal path but I found that the schematic by kevin (Thanks for the hard work!) is only part of the circult on Peterc's PCB (Thanks for the pcb work too!).

Is there any full schematic of the PCB including the PSU parts and some bypass caps?

Thanks
laiben


Post a link to some "Close up" pics & I'll take a look.

I've built a few of these with no problems.
The Schematic really isn't missing much at all.

Did you install the jumpers???


do you mean the balance/unbalance jumper? yes. I short the jumpers like this for balanced output:
(http://i4.photobucket.com/albums/y136/laiben/DIY%20Night%20EQ/RIMG2063.jpg)

BTW I will wire the other channel to see if it works.. Thanks for looking Kevin!

laiben
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: idylldon on May 04, 2008, 12:13:27 PM
A quick question:

Right below R26 is a jumper labeled "OR link."  Is this used instead of R26 in some instance or do both of them have to be in place?

Cheers,
--
Don
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: laiben on May 04, 2008, 12:32:42 PM
Quote from: "idylldon"
A quick question:

Right below R26 is a jumper labeled "OR link."  Is this used instead of R26 in some instance or do both of them have to be in place?

Cheers,
--
Don


As I understand if you do not short the "OR link" below R26 the bypass LED will not work.

BTW there are two R26s in the PCB, I am talking about the one next to the switch.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: keefaz on May 04, 2008, 12:38:13 PM
I think 0R means 0 ohm resistance, no ?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: idylldon on May 04, 2008, 01:41:27 PM
Thanks, guys!  Yeah, I noticed the other direct links were also labeled 0R, which, as you suggest means a "zero ohm" jumper.  I guess it was a bit of a "duh" moment for me!

Cheers,
--
Don
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bluezplaya on May 06, 2008, 04:00:03 PM
I'm trying to wire the bypass LED's to the boards and was curious how to do that. I see 4 holes but have only 2 legs on the LED. Can anyone clarify?

Thanks,
Adam
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: laiben on May 06, 2008, 09:50:19 PM
Quote from: "bluezplaya"
I'm trying to wire the bypass LED's to the boards and was curious how to do that. I see 4 holes but have only 2 legs on the LED. Can anyone clarify?

Thanks,
Adam


Check the trace on the PCB. You can just install one LED and leave the other two holes open. I have no idea why it design like this, maybe the designer think some builder want two bypass LEDs? BTW check the voltage of the bypass LED, don't burn it.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on May 07, 2008, 05:56:30 AM
I think I left that in just to confuse everyone..... :wink:


I can for the life of me remember why I did that. As Laiben says, just use 2 holes.

Regards
Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: idylldon on May 10, 2008, 04:41:32 PM
EDIT:  Ah, a boneheaded move on my part.  I had missed the correct value for R48 by one decimal point!  I'll leave this posted as it might help someone as absentminded as I've been lately.  I lost my mother a couple of months ago and just haven't been tracking too straight since then.  It's a hard weekend as it would've been her birthday as well as Mother's Day.

Well, I finished up my build and am having a small problem, which is most likely something I've connected wrong.  Here it is:

When the EQ is engaged the bypass LEDs are lit, but the EQ works and sounds excellent.  (EDIT:  On further inspection, it appears the LEDs are supposed to be lit when the EQ is engaged and dark when bypassed--correct?)

When I move the bypass switches to "bypass" mode, the gain goes through the roof and I get a completely distorted sound.  I've tried reversing the wires going to the outside poles of the DPDT toggle switch, but it's still the same problem

I have the same problem on both boards and I'm using it unbalanced (links in place) wired into my Neotek's patch bay, which runs at +4 unbalanced.

Here's a pic:

(http://home.mindspring.com/~idyll/NightEQinside.jpg)

Any ideas?  

Cheers,
--
Don
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: idylldon on May 10, 2008, 11:19:06 PM
Just wanted to give Kevin and Peter kudos for such a great project.  Now that it's done and hooked up to my console, I can see that it will get a lot of use.  I've been looking for a good EQ for mixdowns for quite a while, but have been hindered by the high price tags.  This project fit the bill perfectly and I saved a ton of money.

Also, thanks to Harpo for the spreadsheet.  It was a piece o' cake to plug in the numbers and adjust the resistors for each pot.  When everything is centered and I switch between in/out, there is no audible difference at all.

Cheers,
--
Don
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: W DeMarco on June 08, 2008, 09:31:46 AM
I installed a w005 brige rectifier in my green psu.  Im sure it will be fine but I hav noticed that most of the posted pics of finished units seem to use a much beefier Bridge rectifier.  Right above idylidons pic looks like a much larger BR.  I have a 500 volt BR but that sounds like overkill.  Would there be a reason not to use the larger,  Shoud I stick with the w005, which I believe is a 50 volt BR?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: W DeMarco on June 10, 2008, 06:56:42 PM
I quess what Im asking is first, are there additional benefits to using a larger bridge rectifier, for example heat dissapation?  Im assuming a 500 volt bridge rectifier handles UP TO 500 volts and rectifies lower voltages as well.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on June 10, 2008, 08:31:52 PM
Quote from: "W DeMarco"
I quess what Im asking is first, are there additional benefits to using a larger bridge rectifier, for example heat dissapation?  Im assuming a 500 volt bridge rectifier handles UP TO 500 volts and rectifies lower voltages as well.


I'm sorry I can't give you a "Definite" answer but a higher rated rectifier shouldn't be a problem. I use 1n1003 - 1007's on my PSU's all the time & the voltages are low... 12v - 60v max. I'm pretty sure these are 200 - 1000v rated parts.

:::EDITED:::  :oops:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on June 10, 2008, 08:46:08 PM
Quote from: "W DeMarco"
I installed a w005 brige rectifier in my green psu.  Im sure it will be fine but I hav noticed that most of the posted pics of finished units seem to use a much beefier Bridge rectifier.  Right above idylidons pic looks like a much larger BR.  I have a 500 volt BR but that sounds like overkill.  Would there be a reason not to use the larger,  Shoud I stick with the w005, which I believe is a 50 volt BR?

Depending on your transformer it might work (didn't look up the datasheet, so assuming yours is 50V/C?). With a 2x15VAC or center tapped 30VAC secondary and for safety 10% line overvoltage this BR will see ~47V (30V * 1,1 overvoltage * 1,414 for peak). Close, but maybe or better hardly enough. The safety margin for 20-50% line transients is still missing. Your transformer secondary may be lower. A 2x18VAC transformer will sure be too much.
Another part is the surge current when powering up. Have a look at OnSemi's Linear & Switching Voltage Regulator Handbook (http://www.onsemi.com/pub/Collateral/HB206-D.PDF).
I'd probably use a BR with more beef (or 4x 1N400x). YMMV
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: rob_gould on June 24, 2008, 04:37:06 PM
I'm trying to sort out resistor values to use 12 position rotary switches to make a 'mastering version' Night EQ.

It's my intention to make 1db steps from -5 to +6.  If these 1dB steps seem too steep in use, I have a second set of boards to do 1/2 dB steps :wink:

I've used the spreadsheet that Harpo kindly supplied to work out the R total, R centre and R series values that I need, but I'm really out of my depth in determining the formula that will calculate the resistor values for my 1dB steps.

Can anyone chime in here and give me a hand?  Am I even heading in the right direction with what I've got so far?

Here's what I've worked out using the spreadsheet:

(http://www.jinxproductions.co.uk/table1.jpg)

thanks :thumb:

Rob
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on June 24, 2008, 06:57:49 PM
Hi Rob,

something like this excel sheet  (http://www.hausverwaltung-heger.de/al_leck_trick/3D-EQ_Stepped_Pot.xls) :wink:

regards
-Harpo
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: rob_gould on June 25, 2008, 04:12:04 AM
Quote from: "Harpo"
Hi Rob,

something like this excel sheet  (http://www.hausverwaltung-heger.de/al_leck_trick/3D-EQ_Stepped_Pot.xls) :wink:

regards
-Harpo


Hi Harpo,

That's fantastic thanks!  Was this already available or did you put it together last night?

Either way, many thanks.   :sam: for that man :grin:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on June 25, 2008, 05:49:47 AM
my pleasure. The hardest part in excel is optical polishing and making it foolproof. This sheet for shure is ugly and without any safety belts. :green:
As you substitute the rev.log 470k and R-series with the calculated values for your switched thingy, you could lower the feedback resistor R30 to something like 10k to 20k. (Make R48 the same value for bypass.) Using a non shorting switch may help the otherwise ~+6dB increasing level between step position.
-Harpo
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: rob_gould on June 25, 2008, 06:29:00 AM
Excellent - more great information.  This looks pretty foolproof even for me!

Non-shorting switches it is.

Thanks Harpo

:sam: again!
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on June 25, 2008, 08:53:58 AM
Hi Rob,

thanks for the  :sam: . Just uploaded a 2nd chart if you also like to limit the max.cut between switching, otherwise the frequency range of the switched filteramp would be missing for the blink of an eye. ..for what its worth.  :green:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: rob_gould on June 25, 2008, 10:36:24 AM
Ah OK - that addition makes sense.

A couple of questions:

What effect will lowering the value of feedback resistor R30 have on the circuit?  

The table gives a total value for RV + Rseries.  Does this mean I should just jumper all the Rseries positions on the boards and use one resistor for each step that combines both values.  Does this make sense?

Thanks,

Rob
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on June 25, 2008, 12:03:58 PM
Quote from: "rob_gould"
What effect will lowering the value of feedback resistor R30 have on the circuit?

lower resistive noise, as also Rin (=RV+Rseries) get lower by the same factor.
For your desired +6dB boost and Rfeedback 10k, Rin will be in the same range as the original version at full boost, but resistive noise is about 80% lower. No idea, if you will notice the difference.

Quote from: "rob_gould"
The table gives a total value for RV + Rseries.  Does this mean I should just jumper all the Rseries positions on the boards and use one resistor for each step that combines both values.

Yes. If you want to keep your Rseries, subtract its value from the chart value. If you lower Rfeedback, your Rseries will also have a different/lower value. The drawing in the excel-sheet (http://www.hausverwaltung-heger.de/al_leck_trick/3D-EQ_Stepped_Pot.xls) should explain it.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dagoose on September 16, 2008, 03:59:11 PM
Hi there!

I have my nite eq running for a while now and still love it!
The only thing is it's not running at unity gain.. In normal use it's no problem but i just build a switch box for my mastering with 3 eq inserts (extended pultec, sontec and nite) and when switching to the nite eq the level drops about 3 db.
What resistor should be changed to what value?
Have checked this thread but couldn't find it and before i just flip in different resistors for experimenting it might be worth checking out before doing that.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on September 16, 2008, 06:20:59 PM
Quote from: "dagoose"
.. the nite eq the level drops about 3 db.
What resistor should be changed to what value?..

There are various spots to tweak this.
Measure the exact level drop, giving maybe -3.18dB. Flip the sign as you want to boost your signal by this amount, giving +3.18dB. Convert this dB reading to an AV-factor =power(10;(3.18/20)), giving 1.4421.
In case you have constant level with all freq.pots centered and air-band in off-position, compared to bypass position, it would be easiest to increase R3 and R4 from 4k99 to (4k99 x 1.4421) =7k196 for the example above.

Next possible spot is increasing the feedback resistor R30 and bypass resistor R48 by this same factor.
Next possible spot is the voltage divider R24/R25.
Next ... :green:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on September 16, 2008, 06:44:56 PM
Quote from: "dagoose"
Hi there!

I have my nite eq running for a while now and still love it!
The only thing is it's not running at unity gain.. In normal use it's no problem but i just build a switch box for my mastering with 3 eq inserts (extended pultec, sontec and nite) and when switching to the nite eq the level drops about 3 db.
What resistor should be changed to what value?
Have checked this thread but couldn't find it and before i just flip in different resistors for experimenting it might be worth checking out before doing that.


This doesn't sound normal... are you SURE you have the jumpers installed correctly :?: They not only lift pins for Bal or Un-Bal operation but they also change the GAIN!

Or is it your "Center point" of the pots your referring to???
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dagoose on September 17, 2008, 03:01:47 AM
Quote from: "khstudio"
Quote from: "dagoose"
Hi there!

I have my nite eq running for a while now and still love it!
The only thing is it's not running at unity gain.. In normal use it's no problem but i just build a switch box for my mastering with 3 eq inserts (extended pultec, sontec and nite) and when switching to the nite eq the level drops about 3 db.
What resistor should be changed to what value?
Have checked this thread but couldn't find it and before i just flip in different resistors for experimenting it might be worth checking out before doing that.


This doesn't sound normal... are you SURE you have the jumpers installed correctly :?: They not only lift pins for Bal or Un-Bal operation but they also change the GAIN!

Or is it your "Center point" of the pots your referring to???


OK, will check the jumpers, it's been some time that i've build it so i'm not sure if they are in ok then.
I'm running it all balanced BTW.
The center points are set correctly, i did it the hard way; check every band with RMAA untill it was flat and then centered the knob, took me about 1 to 2 hours but it's completly flat when set to the center position.

I'll keep you posted! Thanks.  :thumb:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dagoose on September 17, 2008, 07:44:29 AM
ok... checked the jumpers but they are all set correctly (balanced) and still have about 6db of gain loss which looks like it is indeed connected unbalanced (6db)
Any idea?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: radiance on September 17, 2008, 08:05:10 AM
Do you also have 6dB lower gain when the EQ is in bypass mode?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dagoose on September 17, 2008, 09:49:12 AM
Quote from: "radiance"
Do you also have 6dB lower gain when the EQ is in bypass mode?


Yep, it's not a hard bypass so it still goes through the circuit then.
Must be something in the summing (5532/5534) so i guess it's just a matter of changing resistors but sure which and what value.

http://www.khstudio.us/DIY%20PICs/Alternate%20output%20view.bmp[/url]
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dagoose on September 22, 2008, 03:00:07 PM
Nobody?  :sad:

Ok... i'll drop my nite eq then and go for this option: http://www.bteaudio.com/products/PEQ3/PEQ3.html  :wink:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on September 22, 2008, 03:16:36 PM
I'm not having this problem so I'm not sure how to help you.  :?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on September 22, 2008, 03:55:04 PM
Not really a fix but a work-around:

Try increasing the 56k2 (R30) resistor to 68k or 82k, this should give a few db boost overall.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on September 22, 2008, 03:55:56 PM
Quote from: "dagoose"
Quote from: "radiance"
Do you also have 6dB lower gain when the EQ is in bypass mode?


Yep, it's not a hard bypass so it still goes through the circuit then.
Must be something in the summing (5532/5534) so i guess it's just a matter of changing resistors but sure which and what value.

http://www.khstudio.us/DIY%20PICs/Alternate%20output%20view.bmp[/url]

so your loss is not ~-3dB but -6dB. Most probably not in the summing stage. (your connecting cables are wierd ballanced for shure?) Doublecheck value of R1, R2, R3, R4, R26, R27, R47 and for no short between U4 Pin6-7 (this is U6 Pin 6-7 on pcb). Case all these are OK and you don't want to search further for a maybe mislabled resistor, you can fix this following my previous posting.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: radiance on September 23, 2008, 05:56:53 AM
Quote from: "dagoose"
Nobody?  :sad:

:


Sorry, forgot to check this post lately...but answers have been given yet.

Your problem is most likely found in  R30, R1, R2, R3, R4, R26, R27 or R47.

How's the crush & blend progressing btw?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dagoose on September 23, 2008, 06:28:49 AM
Quote from: "radiance"
Quote from: "dagoose"
Nobody?  :sad:

:


Sorry, forgot to check this post lately...but answers have been given yet.

Your problem is most likely found in  R30, R1, R2, R3, R4, R26, R27 or R47.

How's the crush & blend progressing btw?


I'm going to check that tonight or tomorrow, must indeed be something with resistors tough i'm almost sure i have the right ones in there.
Might change some resistor values as stated in some post before (r3 / r4) which i missed in some strange way, my mistake  :oops: .

C n B is also on my todo list but still waiting for some free time..
i need longer day's or shorter nights..  :green:

BTW: how about that nite VST?  :shock:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on September 23, 2008, 07:35:49 AM
Quote from: "dagoose"
..., must indeed be something with resistors ...

not neccesarily. With signal present measure AC-voltage at your jumperd for ballanced xlr-output. Between xlr-pin3 and 0V should read the same value as between xlr-pin2 and 0V (flipped polarity doesn't matter). Case not, remove the short at U6 Pin6-7 (this is U4 Pin6-7 on schematic).

-Harpo
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: radiance on September 23, 2008, 11:04:44 AM
Quote from: "Harpo"
remove the short at U6 Pin6-7 (this is U4 Pin6-7 on schematic).


Is this a usual suspect for F*@K ups?


Don't see no short on the scematic.....
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dagoose on September 23, 2008, 11:29:11 AM
Quote from: "radiance"
Quote from: "Harpo"
remove the short at U6 Pin6-7 (this is U4 Pin6-7 on schematic).


Is this a usual suspect for F*@K ups?


Don't see no short on the scematic.....


i don't get it either, do you mean there is a fault on the board or something?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on September 23, 2008, 11:44:10 AM
Quote
i don't get it either, do you mean there is a fault on the board or something?


The board should be fine, no-one has reported a fault with it.

Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on September 23, 2008, 12:33:50 PM
There is no fault on the board and no short in the schematic.
The summing amp out connects to xlr out via J2-pin3, operating as designed and giving the inverted signal voltage.
If you accidently have soldered a short between pin 6-7 (it can be a little tight between IC-pins and from murphys law 'if sh*t can happen, it will'), this would be a zero R in parallel with the 10k (2x 20k in parallel) feedback resistors, giving a total of zero R as feedback resistor. This is an inverting gain stage with Rin 10k and will result in voltage gain of 0 instead of -1. This stage then goes to your xlr out via J2-pin2 with a constant 0V instead of your re-inverted signal voltage.
Connecting it ballanced (between xlr pin 2-3), you get signal on output, but with a 6dB loss.  :wink:
If the jumpers were set for unballanced operation in this case, output would be - silence.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: king-rb on September 26, 2008, 01:56:45 PM
i will do a night eq with boost only!

so is it right that i can use 50k rev lin pots for this=?

then +-0 is on the full left and i can boost linear up to the max (+20db)

on the air band i will use 500k rev lin pots ... this should give me more place to handle the dbs...

is this right=?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on September 26, 2008, 03:40:24 PM
yes. btw. pots are rev.log (rev.lin wouldn't make much sense:-) ).
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: king-rb on September 26, 2008, 06:54:22 PM
hmmm but if i want linear boost then lin would be nice or not=?
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on September 26, 2008, 07:13:00 PM
Quote from: "king-rb"
hmmm but if i want linear boost then lin would be nice or not=?


You're not understanding... it's not that simple.

If you use a Lin. Pot, then most of the range will be bunched up at one end... you won't like it. It will be hard to dial it in.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: king-rb on September 27, 2008, 06:11:37 AM
coool thx... will check it out!
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: king-rb on September 27, 2008, 06:37:21 AM
hmm second option.. if i want to smaler the gain rage to.. around +-5 db what can i do..
add a resistor in serie and use potis with smaler resistance=?

sieries resistor around 25k and 250k rev log pots.. is my idea
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on October 01, 2008, 09:18:01 PM
Quote from: "king-rb"
hmm second option.. if i want to smaler the gain rage to.. around +-5 db what can i do..
add a resistor in serie and use potis with smaler resistance=?

sieries resistor around 25k and 250k rev log pots.. is my idea

Hi Ludwig,

with series resistor 25k and a 250k rev.log.pot the feedback- and bypass resistor would have to change to 50k in order to get about 0dB with pot centered, giving a range from -14,8dB to +6dB.

The series resistor is setting the max gain. For your wanted +5dB this will be a voltage gain of 1.78. The rev.log.pot in series to this resistor, when dialed full ccw is setting the min gain. For your wanted -5dB this will be a voltage gain of 0.56. You want the summing amp to operate within these margins, so with the actually given feedback resistor 56k2, the series resistor would be (56200/1.78) 31k6 and the pot would be (56200/0.56 - 31600) 68k3 with a value of about 24k6 at its center position. I doubt, you can source such a pot. You may play with the feedback resistor value to get a better availiable pot, but keep in mind the pot value at its center position (about 10% of its value).
For a stepped +/-5dB gain solution have a look at the excel sheet from this topic, page 43.
-Harpo
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: king-rb on October 02, 2008, 09:50:43 AM
thx harpo great!
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on November 11, 2008, 08:55:14 AM
Just wondering, does anybody have a copy of the manual of the EQ3D ?
And would want to share a scan ?
Apologies if I have missed it, but I don't think I've seen it so far.

Thanks  :thumb:

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on November 11, 2008, 02:14:57 PM
Quote from: "clintrubber"
Just wondering, does anybody have a copy of the manual of the EQ3D ?
And would want to share a scan ?
Apologies if I have missed it, but I don't think I've seen it so far.

Thanks  :thumb:

  Peter


Hey Peter,
Mentioned it a couple times but it's prolly lost in the ocean of posts. :green:

I never could find one... only general info when searching on the net.
There WAS a site that was still up but I'm sure it's gone now... wish I saved it.   :mad:
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on November 11, 2008, 05:37:09 PM
Quote from: "khstudio"
Quote from: "clintrubber"
Just wondering, does anybody have a copy of the manual of the EQ3D ?
And would want to share a scan ?
Apologies if I have missed it, but I don't think I've seen it so far.

Thanks  :thumb:

  Peter


Hey Peter,
Mentioned it a couple times but it's prolly lost in the ocean of posts. :green:

I never could find one... only general info when searching on the net.
There WAS a site that was still up but I'm sure it's gone now... wish I saved it.   :mad:

Hi Kevin,

Thanks for answering, oops, must have missed that or who knows your answer got lost in my own ocean of little grey malfunctioning stuff  :wink:

Anybody else perhaps ? Just wondering... always potentially interesting to read what the designers had in mind.

Bye,

  Peter
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on November 11, 2008, 06:13:07 PM
Wow... I just found the info & specs I copied from the web & the NTI website.
Quote

The AirBand™ EQ
The EQ3-D

$995.00   
Technical Manual for the EQ3-D
$5.00   
Informational Brochure for the EQ3-D
$FREE   

"The Magic Is In The Air"
________________________________________
The EQ3-D is a six-band, two-channel dimensional equalizer with separate channel controls for each of the six bands. It is a true stereo system with total channel-independent electronics and Filters. Each of the First five bands is 2.5 octaves wide with potentiometers that allow For a maximum adjustment of ± 15 dB. The sixth band is the AirBandTM and includes the Veri-Air Feature allowing an adjustable elbow frequency on the AirBandTM shelf of between 2.5 kHz and 40 kHz. The sixth band allows for a maximum gain of 20 dB. The EQ3-D has headroom of 25 dB. It provides support for balanced or unbalanced XLR inputs and outputs.   
________________________________________

SPECIFICATIONS - EQ3-D
________________________________________
Frequency Response   
10Hz 125kHz   ±0.5 dB
5Hz - 330kHz   -3 dB
      
Input/Output   
Input Impedance   20 K
Input level at output clip   43.8VP-P
Output Impedance   50S
Output clipping level   41.3V, P-P
Voltage gain(+) loss(-) bypass/Flat   -0.5dB
Maximum output   +25 dBm
      
Signal-To-Noise   
Bypass   90.0 dB
Flat   89.9 dB
Hum   Unmeasurable
      
Signal-To-Crosstalk
(30 kHz low-pass)   
Bypass   No crosstalk
Flat   No crosstalk
      
THD (30 kHz low-pass)   
Bypass   0.005%
Flat   0.005%
      
Phase Shift   
Normal operating range   10 Deg.
Maximum   30 Deg.
      
Line voltage   100 - 250 VAC, 50-60 Hz
      
2 channels, 6 bands per channel (5 + AirBandTM)   
      
Dimensions   
Front panel   1.75" x 19"
Rack depth   7.5"
Rack weight   7 lbs.
________________________________________

________________________________________
What makes the EQ 3D a Spectrum Rectifier®?
________________________________________
The EQ3D does a combination of 14 things that no other piece of equipment in the world can accomplish. This is why we had to invent a new the word spectrum rectifier tm. The following 14 things make the EQ3D a spectrum rectifiertm !
 
Virtually No Phase Shift
All of the Nightpro products create virtually no phase shift in the signal -- Even at full boost!
 
10hz to 40,000hz Adjustable Bandwidth
The EQ3D allows users to control the spectrum all the way from 10hz to 40,000hz, a control feature no other sound enhancement tool can match.
 
The "Air Band"
The EQ3D allows variable control of the highest end of the frequency spectrum. This patented technology provides a clarity and sense of intimacy to your mix.
 
Universal Power Supply
The EQ3D contains a power supply that can be used anywhere in the world without power adaptation.
 
40db Control Range
The EQ3D allows a control range of 40db on each band.
 
Lightweight Design
The EQ3D uses a light weight power supply to achieve the needed component requirements with a much lighter weight than required by conventional power supplies of similar outputs.
 
Single Rack Space
The EQ3D has created a single rack space unit that provides the same great sound quality as it larger products with similar analog processing capabilities.
 
Broad Design Slopes
The EQ3D's bands are designed with an extremely wide Q. This approach yields a more natural change in frequency content than a traditional equalizer.
 
Truly Flat Frequency Response
Unlike an equalizer the EQ3D has a completely flat frequency response whenever each band is at the same level-- the response is even flat when each band is turned all the way up!
 
The Worlds Most Musical Sound Enhancement System
The EQ3D's natural sound quality has made it the worlds most musical sound enhancement system.
 
Picture Perfect Square Waves
Even during equalization, the EQ3D can process a square wave with perfect accuracy. Try it for yourself!
 
Completely Dolby Pro-Logic Compatibility
The EQ3D's absence of phase shift allows it to process Dolby encoded signals without deterioration of the encoded signal.
 
The EQ3D can Rectify Your Spectrum
For more information contact us at:
Nightpro International
1680 West 820 North
Provo, Utah 84601
Tel. 801.375.9288 - Fax. 801.375.9286
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on November 11, 2008, 06:15:45 PM
And other INFO I found (I think from SOS?)

Quote

NTI NIGHTPRO EQ3D
DUAL-CHANNEL EQUALISER
 
High-quality equalisers have the magical property of allowing you to tweak tonal content, while themselves remaining practically invisible to the ear. HUGH ROBJOHNS checks out a contender from an American company new to the UK market.
 
The NTI Nightpro EQ3D is an equalizer -- a dual-channel, 6-band equaliser. Those few words might appear dull enough to encourage you to turn the page in search of something with lots of flashing lights, pages of set-up menus or a MIDI port, but in this case, that would definitely be your loss!
The EQ3D is not just an ordinary equaliser; it offers something a little unusual in the way of equalisation: sheer musicality. This EQ manages something that few others achieve, intended to serve as a mastering equaliser, allowing gentle 'sound tailoring' to breathe some top-end life back into a tired mix, or give a gentle bloom and weight to the low end. What it won't do is cure a honking PA system, or notch out the hum from a guitar amp.
It has often been said that a really good equaliser cannot be heard. I'm not sure I completely support that point of view, but certainly it's possible to apply extraordinarily large amounts of EQ with the EQ3D before it becomes obvious. The inclusion of Nightpro's 'AirBand' high-frequency shelf section also produces far better results than cheap enhancers when it comes to putting the brilliance back into a recording.
MECHANICALS
The EQ3D is housed in a 1U rackmounting box which is a slim 195mm deep. The top and bottom panels can be removed (after releasing a multitude of screws) to provide access to the internal circuitry and a couple of configuration jumpers.
The rear panel is extremely simple: just a pair of male XLRs for the outputs, a pair of female XLRs for the inputs, and an IEC socket for the mains electricity. The EQ3D features a switched-mode power supply which can accommodate both 110V mains or the UK 240V rating.
The unit is shipped with the audio connections configured for unbalanced operation, but it's a simple matter to move a couple of jumpers inside to provide full electronic balancing of inputs and/or outputs, as necessary. The majority of my testing was carried out with the unit in balanced mode, but there was virtually no practical difference between the two formats in terms of audio performance.
Internal construction is to a very high standard, with components mounted on three circuit boards: one for each audio channel, and a third for the switched-mode power supply. Components are of good quality, and the active audio electronics appear to be made up entirely of the industry-standard NE5532 operational amplifiers. The supplied specifications claim an overall bandwidth of 5Hz-330kHz (-3dB points), a signal-to-noise ratio of 90dB, and total harmonic distortion of 0.005% -- all of which is very respectable indeed.
The front panel is painted a very attractive electric blue colour, with silver labelling and graphics. A rocker-style power switch is placed at the extreme right-hand side, and there are two complete sets of colour-coded controls (one set for each channel), with independent bypass buttons in the centre of the unit. There's no provision for accurate stereo linking between channels, and I would not recommend the EQ3D be used on stereo material. I found it hard to match settings between channels (especially with more extreme settings) and the inevitable result of this is blurring and instability in the stereo image.
SPINDLES WITH KNOBS ON
Each channel boasts five independent EQ bands (all offering up to 15dB of boost or cut), plus the AirBand, which is boost only. Each section has a low Q-factor (to minimise phase shifts -- a key part of the sound quality of the EQ3D), resulting in a broad bandwidth of about 2.5 octaves. This wide bandwidth of each section, combined with their frequency spacing, ensures that they overlap each other nicely, and will interact smoothly to produce many different and musical tonal variations.
The leftmost control for each channel is the 'sub-band', which is centred on 10Hz and has a black knob. The adjacent bands (with blue, green, and red knobs respectively) are centred on 40Hz, 160Hz, and 650Hz, and these all have bell-shaped symmetrical responses. The next band is centred on 2.5kHz, with an orange control knob, and this has a high-frequency shelf response (ie. everything about the turnover point is lifted or reduced).
Unfortunately, none of these controls has a centre detent to define its unity gain position, although the scale around each knob is clearly marked from 5 to zero and back to 5 -- zero being the unity gain position. However, the manual points out that because only very small amounts of boost or cut are normally needed, a centre detent on the knobs would be a hindrance rather than a help. After using the machine, I think I would agree with this philosophy.
Just to the right of the 2.5kHz control is a red peak overload LED which illuminates when the circuitry runs out of steam! In practice, you have to abuse the unit pretty severely to warrant illuminating it, and the EQ3D seemed to have more than enough headroom for realistic settings.
The last band is the AirBand, which also has a high-frequency shelf response. Its yellow boost control is marked 0 to 10 (although it still only provides a maximum of 15dB boost), and the adjacent blue switch determines the turnover frequency. This last switch control is called VariAir and has six positions, which offer turnover frequencies of 2.5, 5, 10, 20 and 40kHz (plus an off position).
PLACES TO PLAY
The EQ3D is a useful tool which brings benefits in a variety of applications. The most obvious one is in recording and tracking, where the unit can be patched between the microphone preamp (or inserted into the mixing desk's signal path) and the recorder. The manual also recommends using the EQ3D in mastering, broadcast, post-production, live sound and home listening systems. I have a few reservations with these last applications -- not because the unit wouldn't enhance the sound quality, because it almost certainly would have a beneficial effect -- but because there is no stereo linking facility on the controls, as mentioned earlier.
I found the EQ3D worked best at the mastering stage, where I could tweak the overall sound character of a mix in a very subtle but surprisingly effective way. In cases where I would normally have plugged in a multi-band compressor to thicken a mix up a little, I found the EQ3D could be used to produce similar results, but with a more open and transparent, and a less artificial, feel.
Using the EQ3D during mixing is a rewarding experience too. With careful setting up, the box really does help to open up the sound, and seems to capture a lot more 'life' than is normally possible with run-of-the-mill microphones and preamps. With top-end mics processed through the best mic preamps, I didn't feel the need to use the EQ3D during recording or mixing, but with more modest equipment the EQ3D was a real help and probably added about 50% to the apparent cost of the front-end!
My favourite controls were those at the extremes of the frequency ranges -- the 10Hz and the AirBand set to either 20kHz or 40kHz -- but you need to be very careful, especially if you're recording onto DAT or a hard disk recorder (anything digital, in fact). The point to bear in mind when tweaking the frequency extremes is that you need to be able to hear what you are doing, and monitoring on limited bandwidth nearfield speakers can be very misleading.
Pulling up the bottom octave with the 10Hz control can add a beautiful warmth and weight on the right material, but can also produce speaker-destroying rumbles on poorly recorded sources. A mix which initially sounded OK on a pair of nearfields shook my living room apart when auditioned on a pair of big transmission-line speakers!
Excessive boost at the top end, particularly with the AirBand set to 20 or 40kHz, can cause all sorts of horrific problems with digital recorders -- especially the earlier ones with baseband analogue anti-alias filtering. Tracks which sounded bright, crisp and full of life on the monitors during the mix often sounded absolutely terrible on replaying the DAT, because of aliasing distortions. This was caused by relatively inefficient anti-alias filtering letting a small amount of the high-level HF signals into the recorder. This breaks the Nyquist rule prohibiting audio above half the sampling rate, and the result is anharmonic distortion of the most unpleasant kind. I found an old first-generation Sony DTC1000 machine suffered the most from this phenomena, but a Sony R500 was very good in an identical situation. Modern A/D converters use a form of oversampling technology and accurate digital filtering to produce much more efficient anti-alias filtering, and the R500 proved just how much better it is!
The moral is that you should be extremely cautious with the frequency extremes. Use only very modest amounts of boost at the low end, and if your monitors don't cover the full frequency range, err towards too little! Clues to look for are meter indications that seem too loud or don't appear to relate directly to the audible programme, and loudspeaker amplifiers that get surprisingly hot or run out of steam earlier than they should. As far as the top end is concerned, the same rules apply; monitoring through your digital recorder will reveal any aliasing problems.
The four middle frequency controls initially appear to be grouped at the bottom of the spectrum, but this is actually where the bulk of the audio energy lives and, in practice, the controls are very well chosen indeed. The range of subtle tonal variation that can be achieved is marvellous and always completely musical, apparently always working in harmony with the instruments. The bands work well together, and careful manipulation of adjacent bands makes an enormous range of control possible, allowing the desirable qualities and characteristics of most instruments to be drawn out.
SUMMING UP
This is without doubt a very useful tool which would inhabit the 'polishing and shining' drawer rather than the 'big hammers' drawer of the sound engineer's tool bench. It works best on material which has been very carefully and cleanly recorded, bringing out the very best qualities and making the whole mix sparkle and shine in a very pleasant manner. It will not make a lousy recording great, but it might make it less objectionable! Being something of an anarchist when it comes to sophisticated signal processing, I would much rather use the EQ3D to sweeten a mix than resort to enhancers and heavy multi-band compression, and I think the end results would be better too. You will have to make up your own mind, of course, but I would thoroughly recommend you try it out.

INVISIBLE MENDING: THE AIRBAND
It may be unusual to see an EQ knob calibrated to 40kHz, but because the EQ3D uses bands which are 2.5 octaves wide, setting the AirBand to the 40kHz position with a lot of boost or cut will still affect audio components as low as 15kHz or so, and will therefore have an audible effect. If you subscribe to the theory that we can perceive frequencies above the nominal 20kHz that our ears are said to respond to, you'll love being able to experiment with the AirBand. If you don't subscribe to this theory, let's just say that you might want to re-consider your views -- I found it an interesting experience anyway!
 
pros & cons
NTI NIGHTPRO EQ3D £1056
pros
• Balanced or unbalanced operation.
• Excellent sound quality.
• Easy to use.
• Very effective.
cons
• Lack of stereo linking.
summary
A very well built and well designed equaliser. The extreme
top and bottom bands are surprisingly effective, and the
middle bands are perfectly placed to draw out the fundamentals
and major harmonics of any musical instrument or voice. Great
for polishing a mix and giving it a professional sound quality.
Title: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on November 11, 2008, 06:21:40 PM
Hi Kevin,

Thanks, yep, that second one is from SOS, but the first section you posted was new to me, thanks  :thumb:
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: clintrubber on November 12, 2008, 06:16:24 AM
Uhhhh, the word 'patented' above made me have a look...

... if it wasn't known or mentioned before already*...

... if this little file was known back then the tracing might have been a bit easier !  8)

http://www.pat2pdf.org/patents/pat5805716.pdf (http://www.pat2pdf.org/patents/pat5805716.pdf)

(describes the full circuit, including component-values - seems to be the last version,
succeeding a few prev. patent-#'s))

... & stay tuned, that Mr C. Maag has patented more stuff....

here's more:
http://www.pat2pdf.org/patents/pat5712591.pdf (http://www.pat2pdf.org/patents/pat5712591.pdf)

and what seems to be a digital version of the idea (someone should write a VST-plugin!):

http://www.pat2pdf.org/patents/pat5892833.pdf (http://www.pat2pdf.org/patents/pat5892833.pdf)


Bye,

  Peter

*: which would surprise me; there will probably be a few patent-# being mentioned on the case or in the manual
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: SaMpLeGoD on November 12, 2008, 10:15:30 PM
Hello!

I finally finished my dual Night Eq, and I builded a little peak indicator for each channel.
Well... I'm trying to realize we're should I connect the peak Indicator to see what's happening with the Input Signal.
Right in the "Hot" (Pin 2) of the Input XLR? after the R25? Right before the R25?
Need help with this!!!

Cheers!!!

Eddie  ;D
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on November 13, 2008, 01:10:03 AM
Eddie

After the first opamp in the circuit. Not sure of the numbers.......

Another option is to connect it on the output, then you will get the signal amplitude with the EQ boost.

Peter
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: SaMpLeGoD on November 13, 2008, 06:19:02 AM
Hello Peter,

Yeah!!! as I suspect... before the R25, after the first opamp's output cap! I'll try not to put at the output, because I'm sure the signal will easily overload when I start to boost the frequencies! so, I'll miss what's really coming thought the EQ's Input!
Thanks a lot for the help!!!

Cheers,

Eddie  ;D
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: W DeMarco on November 17, 2008, 04:07:36 PM
I brought my eq3d into the studio to test her out and brought her right home.  Havin some probs.  Voltages are fine.  In bypass and un bypassed I get a lot of distortion as well as a very low level.  Still happens without the pots connected.  I can also hear the frequency changes when not bypassed and turning the pots.  Two things might be affected but I thought they wouldnt hurt. 

1 I used the air switch in reverse but all of the connections are still relevant to each of the poles.  A went to B and A2-6 went to Bs 2-6 on the board...  B went to A and Bs 2-6 went to As 2-6 on the board. 

Also I connected the solder tabs on my 500k pots together instead of sending all 3 tabs to the board.  in other words two of the pots tabs are connected together with 2 interconnects going to the board.  Anyone having this problem as well?

It doesnt seem like the two things above would affect anything, the prob still occurs bypassed.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on November 17, 2008, 04:29:05 PM
I brought my eq3d into the studio to test her out and brought her right home.  Havin some probs.  Voltages are fine.  In bypass and un bypassed I get a lot of distortion as well as a very low level.  Still happens without the pots connected.  I can also hear the frequency changes when not bypassed and turning the pots.  Two things might be affected but I thought they wouldnt hurt. 

1 I used the air switch in reverse but all of the connections are still relevant to each of the poles.  A went to B and A2-6 went to Bs 2-6 on the board...  B went to A and Bs 2-6 went to As 2-6 on the board. 

Also I connected the solder tabs on my 500k pots together instead of sending all 3 tabs to the board.  in other words two of the pots tabs are connected together with 2 interconnects going to the board.  Anyone having this problem as well?

It doesnt seem like the two things above would affect anything, the prob still occurs bypassed.

I'm willing to BET you don't have the "JUMPERS" installed correctly for Bal or Un-Bal (+4 or -10) operation. ;)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: W DeMarco on November 17, 2008, 06:34:07 PM
Right on, I thought this might be the prob.  Figured it was safer to ask those who were successful with their builds tho! :)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: mitsos on November 17, 2008, 07:07:51 PM
Hi Kevin, did you ever, or do you plan to, make some form of air-only PCB available?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: W DeMarco on November 24, 2008, 10:04:05 AM
sO i MADE THE JUMPER changes and it worked out well.  I think the left channel is a bit quieter than the rght.  Im wondering if there is a resistor or two I can match better?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Dr nEon on February 04, 2009, 06:50:51 AM

Hi guys!

I'm starting to think about putting together one of these night eq's, after reading this enitre thread..looks like a great project!

I'm trying to understand the circuit , and would like to know how crucial is it to adhere to the very specific resistor values..

On the nice BOM , many resistors are given ALT values , which I'll probably go for as I have most of those "alt"'s in stock... but can anyone explain what will be the result of using alternate values?

Also, I see there are some resistances which are not given alt values... ie 5k11 . Does this mean that these values have to be strictly adhered to , if no alt is given. Would 5K1 not suffice?

I wouldn't normally fret to much about this kind of thing , but this eq circuit is very different to other projects I've done .

Another question..I see a lot of "times 10" going on...  I assume that if you were to select 2k in place of 2k05 , then you should also select 20k in place of 20k5 ...... would this make sense?

I'm imagining that all the alt values probably just shift the centre frequencies a little , but that's just me guessing!

Cheers in advance!

nEon.






Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on February 04, 2009, 09:32:29 AM
Neon

I have used the less precise values like 20k & 5k1 with no problems at all.

Peter
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Dr nEon on February 04, 2009, 05:20:16 PM

Ok , glad to hear that , Peter ! :)

Many thanks

nEon.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: okgb on February 15, 2009, 09:24:13 AM
Manual if anyone is interested

http://cgi.ebay.com/NIGHTPRO-EQ-3D-DIMENSIONAL-EQUALIZER-user-MANUAL-rare_W0QQitemZ160315545926QQihZ006QQcategoryZ23788QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: lonesomehank on February 19, 2009, 02:28:36 AM
Mouser is completely out of stock on the Lorlin switches (Part #10WA165) and won't have any more in stock for roughly 12 weeks......can anyone recommend a suitable replacement that i could order from Digikey?........also having a hard time finding the Digikey part # for the larger Molex 3pin 'power' connectors as well as a part # for the appropriate heat sink...i need to go through Digikey as they actually deliver the next day here in Montreal and don't nail me with outrageous brokerage fees....
.......yup......my very first build.....guess it shows......any help greatly appreciated.......super excited to get this eq up and running.......such an amazing project!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MikoKensington on February 19, 2009, 09:20:56 AM
You can find the same jazz from E-Switch. 
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=EG1954-ND
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: gar381 on February 19, 2009, 11:19:36 AM
Nice Find Miko !

GARY
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: lonesomehank on February 19, 2009, 03:55:39 PM
You can find the same jazz from E-Switch. 
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=EG1954-ND


thanks!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: pedroplanet on February 19, 2009, 08:09:02 PM
I'm trying to reach Peter but he's not replying, does anybody has spare PCBs for this project?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: pedroplanet on February 21, 2009, 09:59:17 AM
or maybe a Night EQ PCB layout for etching?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MikoKensington on February 21, 2009, 12:28:47 PM
Peter sometimes has trouble with his email.  My work email couldn't get through to his.  But my gmail account worked fine.  If you have another account, try it.  He's also a busy fella. 
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Dr nEon on February 26, 2009, 09:54:31 AM

Hi guys!

Just a quick question about how is the best way,sonically, to implement the bypass switch.

I see the pcb accommodates an alps pcb mount push switch. nice and direct .

However,on purushas front panel , the two toggle switches are centred on the panel...much nicer and convenient for in out stereo a/bing . But presumably ,this means that length of the wiring to the pcbs is different for each channel .

i.e the wiring to the left board will be very short , whereas it will be a full boards length to the same spot on the Right channel.

just wondering if anyone has investigated this.  In practice, is the difference negligible?

I'd like to go for the centred toggle idea , but sonic integrity is king , and I'll happily go for the pcb pushbuttons if it is ultimately cleaner. I'd be hand matching every component , to match the stereo as best I can ,within my control , so I guess the bypass lead length becomes an issue..

Sorry if it sounds pedantic...it's not meant to !

cheers!

nEon.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Dr nEon on February 27, 2009, 04:40:52 AM
Hi again!


In addition to the above question , it occurs to me now that those folks using purusha's case have the pcbs mounted on the base , with all pots on flying leads ,anyway...so the issue of bypass switch wiring is probably academic.

However , this leads to another question re mounting the night eq...

Has anyone out there done a version where the pots are soldered onto the pcb , and the whole thing is panel mounted , so that the entire card is hanging from the pots , in the same way that the calrec eq is mounted.

I ask because I don't know yet how heavy the populated pcbs are gonna be , and whether or not the strength of the pot connections will be able to cope over the long term ,  without the board sagging.  In the case of the calrec , the dual ganged pots give a certain strength to the arrangement,helping support the boards , and spread the load,as it were...  but the night eq is onlysingle gang pots...not so rigid,maybe?

Any stories anyone , or pics of night eq's ?

cheers

nEon
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: kb on March 03, 2009, 10:18:07 AM
I've read this topic for a long time very interesting but anyway....Anybody have an original manual in pdf file?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Dr nEon on March 08, 2009, 03:09:59 PM

..One Final Question!


 Would it be a good idea to use a dpdt switch on each channel , to select the bal/unbal jumper positions ?


I can see myself using the night eq in a couple of ways in my studio..either on channel insert via my unbalanced patchbay...or sometimes over the mix bus , using short balanced leads to run into a mix compressor . So I'd need to have the flexibility of selecting bal or unbal modes ,rather than committing to one or the other by soldering those jumpers.

Maybe someone has already tried this , or can verify that this idea makes sense...

Cheers!

nEon.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on March 08, 2009, 03:47:27 PM
Not new but working idea (mine is wired this way). See schematic (2nd link from the 1st post @ pg1 from this thread).
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: [silent:arts] on March 08, 2009, 04:14:35 PM
best way is to use an output stage where this doesn't matter ...
not the best idea if YOU (or ME) have to think about it in witch position a switch is set.
I would either go balanced with a balancing chip, or a cross coupled pair output.
(same way for some other projects here)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Dr nEon on March 09, 2009, 06:13:22 AM

 Thanks guys,

Harpo , that schematic is the one that got me thinking , since it's drawn as a switch ,but I'd only seen people doing it a wire link jumpers. So it's good to hear you have done it as a switchable thing.

I would put the switches on the back of the unit.  I presume you had to keep the cable length as short as possible.


I've had to implement 0dB / +6dB switches on my other stuff  too .  I always put xlrs on the back , altho' the gear spends half it's life in my home studio , where the soundcraft2400 p/bay is unbalanced..unfortunately!

Cheers

nEon
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Dr nEon on April 23, 2009, 03:58:23 AM

 Hey everyone!

 New question re the night eq..

 After tweaking the various resistor values , using the excel calcuator for accurate pot centres, it looks as though I have to change the 22pF capacitor down to 18pF , since my R30 has now become 64,000..

 I don't have np0/c0g type in that value , which the bom calls for , but I do have standard 18pF ceramic disc in stock , or  polystyrene (or ,rather,a combination of styrene to get the correct value..).

 Would either of these be ok to use in this position?

 Or do I really need to find a c0g/np0 cap?

cheers
 
nEon.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: keefaz on April 23, 2009, 04:53:32 AM
C13 with R30 form a lowpass filter with -3db point at 118kHz with 22pf cap and at 144kHz with 18pf cap
Now if you can hear a difference in sound with -3db attenuation at thoses frequencies, you're not an human  :D
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Jed on May 16, 2009, 08:06:20 PM
Hey, does anybody have a photo showing how the lorlin is wired?

I think I understand, but the photo from the link here (http://www.groupdiy.com/index.php?topic=19789.520) seems to be gone...

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: giltmastering on May 23, 2009, 12:49:52 AM

i just found this thread for the first time.  i've wanted to build one of these as well.  we have an original 3ru  NTI EQ3 here at the studio.  this unit sounds amazing.  i don't know the differences between this and the 3d but we can use ours to figure it out.
i opened it up to post some pictures here. sorry the quality sucks, it's off my phone.   


(http://i122.photobucket.com/albums/o243/lugemusic/005.jpg)
(http://i122.photobucket.com/albums/o243/lugemusic/009.jpg)
(http://i122.photobucket.com/albums/o243/lugemusic/011.jpg)
(http://i122.photobucket.com/albums/o243/lugemusic/009.jpg)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Anthropic on May 23, 2009, 04:32:05 PM
Those are some rare pictures!  Thanks for posting them!  Anything you can do to find out more would be fantastic (especially concerning any input or output transformers).  If you can get some clearer/closer pictures, that would be fantastic also.  This is what we've been waiting for, in relation to this particular EQ project.  Thanks again.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: giltmastering on May 23, 2009, 06:33:03 PM
i'm ready to help with this project.  i would love to build one myself.  this unit belongs to a friend in the studio here and he's willing to let me dissect his unit. i don't see any input and output transformers near the XLR connectors. the might be elsewhere hard to see.  i will look again.  i will try to post better pictures.  he also has a mic pre that he loves.  it has the air band as well.


Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: okgb on May 23, 2009, 07:53:04 PM
the schematic kev made has no signal xfmrs
but what are the concentric pot functions
on the pix you posted
gain & what ?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on May 24, 2009, 08:19:44 PM
but what are the concentric pot functions
on the pix you posted
gain & what ?

Yes... what are they for?

The 3RU's basic circuits aren't any different (from what I've been told) but as you can see they use the POWER ONE's for the power supply as opposed to the "Switching PS" in the smaller unit + all those Grayhill switches for "Recall"... which is nice but doesn't make the circuit or "sound" different. I do think the better PS would help the sound though.

That second pic you posted is the Pre, which I've never used.


Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: briomusic on May 25, 2009, 05:35:58 AM
I am currently trying to breadboard just the switchable shelf part of the night eq and it's not working too well, yet  :(
The circuit is passing audio, but it sounds very thin, and the pot acts as a level control.
I have basically just used the top row of this schematic:
http://www.khstudio.us/DIY%20PICs/3D%20EQ%20-%20FULL.bmp - ignoring the bypass arrangements and making the shelf fixed at 5khz (I don't mind switching the capacitors/frequency manually while this is on the breadboard)

Do I need to have all the sub circuits going to get a full frequency signal?

Thanks in advance!

(edited as I respect Kevin's decision to hold back air eq schematic)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on May 25, 2009, 06:12:43 AM
I am currently trying to breadboard just the switchable shelf part of the night eq and it's not working too well, yet  :(
The circuit is passing audio, but it sounds very thin, and the pot acts as a level control.
I have basically just used the top row of this schematic:
http://www.khstudio.us/DIY%20PICs/3D%20EQ%20-%20FULL.bmp - ignoring the bypass arrangements and making the shelf fixed at 5khz (I don't mind switching the capacitors/frequency manually while this is on the breadboard)

Do I need to have all the sub circuits going to get a full frequency signal?

It would help to have a look at the air eq schem (as opposed to the full 3d eq) but unfortunately I get a "permission denied" error when following this link:
http://www.khstudio.us/DIY%20PICs/3d%20%20AIR%20EQ.bmp

Would anyone be willing to share the air eq schematic with me?

Thanks in advance!
You'll need R48 in parallel with the air band amp and the R24/R25 common attenuator in front ('bypass' at R48 now connects to 'to sum' instead of 'bypass' at sw7), so the air band can add up to your (actually missing) program signal.
Another way is, to build a derived lowpass from program and air band to also make boost/cut for the air band possible.
Just my 2ct.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on May 25, 2009, 06:26:10 AM
I am currently trying to breadboard just the switchable shelf part of the night eq and it's not working too well, yet  :(
The circuit is passing audio, but it sounds very thin, and the pot acts as a level control.
I have basically just used the top row of this schematic:
http://www.khstudio.us/DIY%20PICs/3D%20EQ%20-%20FULL.bmp - ignoring the bypass arrangements and making the shelf fixed at 5khz (I don't mind switching the capacitors/frequency manually while this is on the breadboard)

Do I need to have all the sub circuits going to get a full frequency signal?

It would help to have a look at the air eq schem (as opposed to the full 3d eq) but unfortunately I get a "permission denied" error when following this link:
http://www.khstudio.us/DIY%20PICs/3d%20%20AIR%20EQ.bmp

Would anyone be willing to share the air eq schematic with me?

Thanks in advance!

Sorry but I asked everyone to NOT share the "AIR" schematic. Not very many even have it.
I shared the FULL version with everyone

You can't just build the hi shelf sections... you won't get any other (or Lower) frequencies except the hi shelves.
What I did wasn't too difficult. But I did spend some time tweaking & listening.

Try making one of the other bands - FULL Band.

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: briomusic on May 25, 2009, 06:33:36 AM
Hi Kevin,

thanks for your response, I completely respect your decision re: the air eq.
since posting the above, I have had a read through the patent application someone posted earlier in the thread, and I understand the circuit much better now

I also appreciate your little hint - glad I am still on breadboard at this stage  ;D

Very curious about your air eq product, make sure to let us all know!

Thanks for your help, I am going to edit the schem request out of my original post.

Harpo, just saw your message, I tried your first solution, but then the air band control didn't seem to have any effect. Now moving on to the "everything-BUT-air"-band approach, which I think both you and Kevin alluded to.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: briomusic on May 26, 2009, 07:04:42 PM
Hmmm, after two more days of experimenting I am closer, but not quite there yet.
I have tried the "bypass-wire + air" method as well as the additional "full-band with its own opamp" approach, and everything sounds great and seems workable after juggling some resistor values around, but there are still some operational hangups...

First of all, is the air band supposed to be boost only? I noticed the scales on the faceplate are +/-5 for most pots, but 0-10 for the airband, what gives?

ETA: just read the SOS review...so boost only it is :)

Secondly - for me (fully) boosting the airband results in a +5dB boost for the entire frequency spectrum down to 500Hz (and below), then at about 2.5Khz I get a 7dB boost and finally a 15dB boost @ 20kHz (this is with the .47uF cap for '20kHz' air).

I am not sure if the latter problem is connected to my struggle with the "program" band, but I observed this phenomenon in both of the setups mentioned above.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on July 12, 2009, 08:04:43 PM
Hi,
I'm just starting to gather the parts to build my Night EQ project.

I read this full thread, so I know that Kevin used 15V rails instead of 18V.

I would like to ask what are all you guys using, 15V or 18V?

anyone else noticed a sound difference?

is that I can't really think , of why it would sound better at 15v, it seems to me that technically it should sound better with higher voltage.

thanks

and Congratulations to Kevin, for all the hard work in bringing this project,
and Peter C also for the PCB's.



Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on July 12, 2009, 08:33:55 PM
Hmmm, after two more days of experimenting I am closer, but not quite there yet.
I have tried the "bypass-wire + air" method as well as the additional "full-band with its own opamp" approach, and everything sounds great and seems workable after juggling some resistor values around, but there are still some operational hangups...

First of all, is the air band supposed to be boost only? I noticed the scales on the faceplate are +/-5 for most pots, but 0-10 for the airband, what gives?

ETA: just read the SOS review...so boost only it is :)

Secondly - for me (fully) boosting the airband results in a +5dB boost for the entire frequency spectrum down to 500Hz (and below), then at about 2.5Khz I get a 7dB boost and finally a 15dB boost @ 20kHz (this is with the .47uF cap for '20kHz' air).

I am not sure if the latter problem is connected to my struggle with the "program" band, but I observed this phenomenon in both of the setups mentioned above.


I think your observations are correct concerning the boosting of lower frequencies when boosting the AIR... YES it's boost only (for that section) & it does reach pretty far down = large/smooth shelf.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on July 12, 2009, 08:43:46 PM
Hi,
I'm just starting to gather the parts to build my Night EQ project.

I read this full thread, so I know that Kevin used 15V rails instead of 18V.

I would like to ask what are all you guys using, 15V or 18V?

anyone else noticed a sound difference?

is that I can't really think , of why it would sound better at 15v, it seems to me that technically it should sound better with higher voltage.

thanks

and Congratulations to Kevin, for all the hard work in bringing this project,
and Peter C also for the PCB's.


You may have gotten confused... I'm using 18v rails!
What I may have mentioned is liking a LOWER AC voltage TX, going into my PS.
To me, when I used an 18-0-18 TX (which measured more like 20-0-20) the sound of the unit was "Stiffer", which I Personally didn't like.
It was subtle but there, for me at least... When I used a 15-0-15 (which measured more like 16-0-16) the sound was less restrictive.

Keep in mind this could have been due to the larger current/Amps TX I used & I would NOT sweat it too much.

To be safe... the rule is to use an AC TX with the same output voltage as your regulated DC output.

Running the rails anywhere from 15v to 18 volts will be fine.
The original unit was 17v rails.

Good Luck.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on July 12, 2009, 11:43:15 PM
oh Kevin,
thanks for clearing that out.

I understood that you were using a 15-0-15 transformer, but I thought that you had your rails also +15v and -15v.

So do your rails measure + and - 18 even though you are using an 15-0-15 transformer?

thanks
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: khstudio on July 13, 2009, 12:29:30 AM
Quote
So do your rails measure + and - 18 even though you are using an 15-0-15 transformer?

YES... & this is what's important!!!

You NEED enough headroom for the Regulators to work properly & I'm on the edge I'm sure.

Remember, me AC out of my TX was higher than 15v.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: SALSA on July 13, 2009, 03:32:58 AM
Hi Whoops,

You might want to check out this very useful tool of Samuel

http://www.groupdiy.com/index.php?topic=21307.0 (http://www.groupdiy.com/index.php?topic=21307.0)

Cheers,

Mike
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: outoftune on July 13, 2009, 12:03:42 PM
sorry if this have been covered already, but...i have many questions. i built one of these myself and am finishing up 3 for a friend! very interested in this circuit and I really like the sound of it.

i've seen pics of this one ( http://www.electrical.com/item.php?page=5&pic=pictures/5-0.jpg )and a few other eq3's with different faceplates, just wondering if they are all the same internally? is the eq3 the same circuit as the eq3d, except with stepped pots? any other magic going on inside those?

has anyone here attempted to build one with the stepped gain controls?

i know khs said the mid point of his pots measured 47k, just wondering if this is with the pots in the circuit or disconnected?

also, regarding opamp selection for the eq3d: i know KHS said it uses JRC 5532's for the lower bands, and signetics for the 2.5k/air & the 5534. i have only been able to find NJM 5532's, no one seems to sell the JRC ones. are these essentially the same thing? i have TI 5532's in there now, but im interested to try something else. anyone have some JRC5532's they'd be willing to sell me?

one last thing, anyone happen to have a scanned copy of the manual for this? i would love to have a look.

and finally THANKS TO KHS, PETER C AND EVERYONE ELSE FOR THIS PROJECT!!! it sounds great, the air band is on all my vocal tracks! i've also had success with using this for some DIY mastering. even with the fixed bands, it can definitely help to clear things up.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on July 13, 2009, 04:45:47 PM
Quote
So do your rails measure + and - 18 even though you are using an 15-0-15 transformer?

YES... & this is what's important!!!

You NEED enough headroom for the Regulators to work properly & I'm on the edge I'm sure.

Remember, me AC out of my TX was higher than 15v.
Hi Whoops,

You might want to check out this very useful tool of Samuel

http://www.groupdiy.com/index.php?topic=21307.0 (http://www.groupdiy.com/index.php?topic=21307.0)

Cheers,

Mike

Thanks a lot for the information and for the link.

I was not even aware of regulators headroom.
I always assumed that if you wanted, for example + and - 18V, you needed a transformer with the secondaries 18-0-18.

I going to study more this subject now, and learn a bit.

thanks a lot
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: outoftune on July 19, 2009, 04:36:25 PM
sorry if this have been covered already, but...i have many questions. i built one of these myself and am finishing up 3 for a friend! very interested in this circuit and I really like the sound of it.

i've seen pics of this one ( http://www.electrical.com/item.php?page=5&pic=pictures/5-0.jpg )and a few other eq3's with different faceplates, just wondering if they are all the same internally? is the eq3 the same circuit as the eq3d, except with stepped pots? any other magic going on inside those?

has anyone here attempted to build one with the stepped gain controls?

i know khs said the mid point of his pots measured 47k, just wondering if this is with the pots in the circuit or disconnected?

also, regarding opamp selection for the eq3d: i know KHS said it uses JRC 5532's for the lower bands, and signetics for the 2.5k/air & the 5534. i have only been able to find NJM 5532's, no one seems to sell the JRC ones. are these essentially the same thing? i have TI 5532's in there now, but im interested to try something else. anyone have some JRC5532's they'd be willing to sell me?

one last thing, anyone happen to have a scanned copy of the manual for this? i would love to have a look.

and finally THANKS TO KHS, PETER C AND EVERYONE ELSE FOR THIS PROJECT!!! it sounds great, the air band is on all my vocal tracks! i've also had success with using this for some DIY mastering. even with the fixed bands, it can definitely help to clear things up.

anyone?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: SALSA on July 20, 2009, 01:52:11 PM
profusionplc.com for JRC's

Cheers,

Mike
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on August 17, 2009, 10:55:11 PM
Hi,
did anyone ever finished the Night EQ using stepped switches instead of Pots?

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: rob_gould on August 18, 2009, 11:23:20 AM

Nope but it's on my list!  I was going to use 1x12 Lorlins with 1db steps. 

The issue here is that using Elma / Grayhill 1 x 24 switches would just be too expensive for this project.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on August 18, 2009, 11:44:45 AM

Nope but it's on my list!  I was going to use 1x12 Lorlins with 1db steps. 

The issue here is that using Elma / Grayhill 1 x 24 switches would just be too expensive for this project.

yes I know.
I would like to do mine with 0,5dbs steps.

I've read the whole thread on this project but I still get a bit confused with the Pot subject.

If I use the 470 rev log pots from Audiomaintenance, I have to adjust the center value (0dbs) changing some resistor values, is that right?

Has anyone done this successfully?

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MrZpliff on August 18, 2009, 05:08:48 PM
I changed my pots to 12 step lorlins.
that way I get around 5dB +/- for each freq.
I did match the pots with resistors, but I want to use it as a stereo EQ, mastering style.

Got 12 pots with center click for sale :P
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on August 18, 2009, 05:25:15 PM
I changed my pots to 12 step lorlins.
that way I get around 5dB +/- for each freq.
I did match the pots with resistors, but I want to use it as a stereo EQ, mastering style.

Got 12 pots with center click for sale :P

Thant's really nice,
what resistor values did you use for the steps?

do you have any docs or info you could provide that could help us?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on August 18, 2009, 07:02:36 PM
Stepped gain could be calculated using my ugly excel chart (http://www.hausverwaltung-heger.de/al_leck_trick/3D-EQ_Stepped_Pot.xls)
good luck
-Harpo
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on August 18, 2009, 07:27:43 PM
Stepped gain could be calculated using my ugly excel chart (http://www.hausverwaltung-heger.de/al_leck_trick/3D-EQ_Stepped_Pot.xls)
good luck
-Harpo

Thanks a lot Harpo,
unfortunatly I'm a newbie and although your document looks great I don't know how to use it.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on August 18, 2009, 08:56:52 PM
less great than ugly, but its not that hard to do. See the little wiring sketch on the right side. The resistors for each step position at the switches are listed in the green cells, with a resistor in parallel (value in the orange cell) to get it less jumpy between switch positions. Each of these building blocks substitute a 470K rev.log. pot (RV36, RV38, .., RV44) with its 5.62K series resistor (R37, R39, .., R45) for each freq.band gain setting part of the summing amp.

Maybe you want to use a 12 pos. lorlin type switch instead, limited to 11 pos. for a center position at step 6, so you just replace the default value '23' with '11' for 'step positions' in the yellow cell. Maybe you want a different cut/boost range (within limits), so replace the default values '5.5' and '-5.5' with maybe '5' and '-12.487' for 'max.boost' and 'max.cut' in the yellow cells. Each time you update a value in the yellow cells for your needs, the whole chart is recalculated and resistor values picked for the closest E96 value to match your plan.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on August 18, 2009, 09:49:50 PM
Thanks a lot Harpo for explaning
it makes totally sense now.

I think 12pos are a little bit limited, but the 24 pos switches seem too big to fit into a 1U rack case.

If I use the 470k rev log pots with center ident,
what's the process that I have to do to make sure the center is correct?




Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on August 19, 2009, 06:20:19 PM
some pages back (~01/2008) my pot tweaking chart (http://www.hausverwaltung-heger.de/al_leck_trick/3D-EQ_PotTweaking.xls) might help you.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on August 19, 2009, 06:56:11 PM
some pages back (~01/2008) my pot tweaking chart (http://www.hausverwaltung-heger.de/al_leck_trick/3D-EQ_PotTweaking.xls) might help you.

Oh my God,
are you the real Harry Potter?

thanks harpo
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on August 26, 2009, 09:50:32 PM
Hey, does anybody have a photo showing how the lorlin is wired?

I think I understand, but the photo from the link here (http://www.groupdiy.com/index.php?topic=19789.520) seems to be gone...



I'm also having problems in wiring the switch, and I've read this full thread and all the explanations.
The Photo is gone also.

My Lorin Switch has 2 Pins in the middle.
A and C

around those theres 12 Pins, marked from 1 to 12


SO:

"A" (Board) should connect to "A"  (center Pin)

B (Board) should connect to  "C" (center Pin)

2 to 2
3 to 3
4 to 4
5 to 5
6 to 6

How about 2-6 ? how should I connect this?

Pins 1 , 7 , 8 ,9 ,10, 11 and 12 are not connected at all?

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on August 27, 2009, 02:39:21 AM
From the old post (edited):

First half of the rotary switch:
The hole marked 'a' goes to the inner pin of a 2 x 6way rotary. The hole marked '2-6' goes to the pins 2-6 (joined on the switch). Shown by the 2 white wires in this pic.

The second half of the rotary:
The hole marked 'b' goes to the other inner pin of the rotary. The individual wires marked 2 to 6 go to pins 8-12 on the switch. Shown by the coloured wires in the pic.

So the first thing to do is to make sure the switch is a 2x6 way. Then check against the circuit diagram.....

I will try & find the pic on my other PCs

Peter
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on August 27, 2009, 08:44:08 AM
Thanks Peter,
that makes much more sense.

The Switchs are 2 x 6 Lorin

if you can find the picture and post it I'm sure no one will ask this question anymore

best regards
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on August 27, 2009, 08:47:33 AM
one last thing, anyone happen to have a scanned copy of the manual for this? i would love to have a look.

anyone?

I think the manual or some similar document was posted in one of the Night Eq threads,
it was just text you could copy and paste into word.
I can't find it right now

Anyone remembers this?

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Brolik on August 31, 2009, 12:23:27 PM
Time for another uninformed question... I've noticed that R29 and L1 are switched on the V2 silk screen, but I don't see it discussed anywhere in this thread. I've also seen them installed both ways on finished unit pics. I assume it's because it doesn't matter whether they are switched (also judging from the traces and schematic). I just want to make sure that I'm not crazy before I precede with this vaguely informed notion. Any help? Thanks.

~Matt Sommer
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on August 31, 2009, 02:29:03 PM
No , you're no crazy.

I noticed the same thing, and by the traces I also assumed that it didn't matter if they were switched.

probably the inductors are not even doing anything at all in this circuit
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on August 31, 2009, 03:35:21 PM
Quote
..I've noticed that R29 and L1 are switched on the V2 silk screen..
R29 and L1 are not switched but always connected to in-phase/hot output.

R32 and L2 are either jumpered between balanced mode or left floating/not connected in unbalanced mode and 0V instead jumpered to out-of-phase/cold output.
The other jumper (you're probably refering to) switches R47 in parallel to R26 in unbalanced mode to make up the otherwise 6dB loss.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: ytsestef on October 06, 2009, 05:20:56 PM
Chimin' in...

Hello everyone. I thought it would be a very interesting project, and when I tried searching for PCBs , Peter told me the Night EQ PCB is out of production. Anyone knows why? Lack of interest? Was it illegal? Are there any gerber files available so one can etch his own? Or do I have to rediscover the whole thing if I want to build one? Maybe someone else still makes them in the forum. What happened there??

I'll try searching around a bit more, then maybe I'll do as advised by Peter and post some "wanted" ad. This is sad, nonetheless, what a pity. All this effort gone to waste and such a brilliant eq out of production  :( :( :(

Cheers
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Slenderchap on October 07, 2009, 02:21:55 AM
Just "for a laugh" I put the Nite EQ in a 500 series module last year;

(http://www.audiomaintenance.com/downloads/5003d_overview.jpg)

Faceplate looks like this;
http://www.audiomaintenance.com/downloads/5003d_front.jpg

and I even did a transformer output option PCB;
http://www.audiomaintenance.com/downloads/5003d_eq_transformer_option.jpg

It worked just fine, but slightly differently from the original in that when you boost a band it brings the "out of band" level down as well so it makes it difficult to overload (consequently the "Sub" band has the effect that the signal gets quieter when you increase the level..... because the "out of band" is basically every thing audible)...

There was one very small error on the PCB which I have now corrected.... but did not get any made.... I was thinking about getting a few boards made and then sending the gerbers to Gustav.....

... does anyone want these ?

Colin
www.audiomaintenance.com
 
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: joe-electro on November 07, 2009, 09:54:53 AM
Beautiful work Colin!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Slenderchap on November 08, 2009, 01:24:38 PM
For anyone who is interested..... I have done the small corrections to the PCB (although I haven't yet built one).

Here is the info;

www.audiomaintenance.com/downloads/prodigy_nite500_electrical.zip
Schematic, parts list, PCB layouts, Gerbers etc.

www.audiomaintenance.com/downloads/prodigy_nite500_mechanical.zip
Faceplate (simplified) and sideplate in FPD format

{The sideplate is purely cosmetic as all the pots are bracketed}

If there is enough interest I'll start stocking the pots and rotary switch etc....

I'm sure the Gustav will be more than willing to make the boards if there is interest.

The information has not been checked.... as I have not as yet built one from these gerber files.... although I presume they are correct, I have known Gerber generation errors to occur when  output from EasyPC

Colin
www.audiomaintenance.com


Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Gustav on November 08, 2009, 03:33:31 PM


I'm sure the Gustav will be more than willing to make the boards if there is interest.


Thanks for the mail Colin.

Ill gather interest and see if its enough to do a run. Ive only been able to sell a few of the 9k 500 series boards, but perhaps people are holding out a bit because they are waiting for the 500 series frames from Volker.

Gustav
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Dirty Gear Pimp on November 16, 2009, 05:00:05 PM
id be interested in 1 or 2 of these eq kits in the 500 format. about how much for a complete kit with board and faceplates ?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: spacecho on December 08, 2009, 06:30:41 AM
hey guys,

i'm nearing completion of this eq and using the power boards provided with the boards (from the green pre (green psu)

have searched everywhere for the schematic to this design can only find the bom.

The bom says that the 1000uf caps are rated for 10v (mouser part number points to a 10v part) - is this correct? i thought it would at least have to be higher than the voltage of the transformer taps (15v)

if not what would a good voltage rating be? i was thinking at least double would be appropropriate? (35v)

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on December 08, 2009, 07:02:36 AM
35v would be fine for those caps.

Peter
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on January 05, 2010, 09:26:42 PM
Hi,
I would like to do a version of the night EQ where instead of having separate controls for the channels, I would only have one control for each band, controlling both left and right channels at the same time.

I was thinking about Dual Gang 470K Rev Log Pots, audiomaintenance has them.

http://www.audiomaintenance.com/acatalog/om-01-055_extended_info.html

Even if the "Air" control and "Vari" switchhad to be independent, it would be great to have only one control for the "Sub" , "40hz", "100hz", "650hz" and "2,5K"

Do you think it's possible ?

thanks
my best regards
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: ytsestef on October 12, 2010, 07:16:45 AM
Thread resurrection! ;D

I'm about to finally start building a stereo pair and I have some questions:

1) Can this thing be powered from the SSL9k PSU? (uses 7818/7819 regs)
Why is the Green PSU a better choice?

2) Due to the facts it's going to be stereo, I want to use gainswitches instead of pots. Is this possible? How should I wire them to the board?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on October 12, 2010, 08:04:24 AM
SSL 9k psu will be fine

In the thread there are MANY posts about using stepped gain
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: ytsestef on October 12, 2010, 09:01:26 AM
Thanks Peter. Ok, then 9k psu it is :D Also, can I get away with 15VA transformer, or should I go for 30VA? I'll power 2 channels. I don't know how many mA each channel consumes...

I read my stuff on the gainswitches, too (should have done that before asking)...

I will use it mainly for bus eq, so I might as well use 12-position switches only, ranging from -5 to +6 dB in 1dB steps OR ranging from -7.5 to 9dB in 1.5dB steps. Should be enough for bus eq, has enough precision and it has fixed frequency/bandwidth anyway, so, I guess it will be wiser to use it for colouring rather than correction... What do you guys think? I could actually do other stuff like boost in 1.5 dB steps and cut in 1dB steps... Any thoughts on that kind of stuff from people who have actually heard this thing?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: ytsestef on October 15, 2010, 06:42:05 AM
What needs to be done in the "boost only" hi-shelving band if I'm using switches? Do I just use Harpo's .xls file with the gainswitch calculator and select only boost values or what?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: gruzina on December 21, 2010, 03:53:28 AM
Hi all can you please send me the full schematic and files too  [email protected]

thank in advenced ari
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: gruzina on December 29, 2010, 09:48:28 PM
please i want to buy the pcb where can i buy it peter or someone help [email protected]
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: earthsled on March 07, 2011, 09:26:50 PM

Many thanks to khstudio, harpo, peterc, and everyone else who has contributed here!

I wonder if anyone is still keeping up with this 5-year-old post???

Okay - here goes -- I'm currently working on a two-layer PCB version of the EQ3D for a rackmount unit (non-500-series).

I've decided to include the clipping circuit on my PCB, and because of this, I've run into a few snags that I was hoping to get some help with...

1. What's the value of C200 and is it necessary? It's not on the schematic, but it appears to connect between pins 5 and 8 of U6... http://www.twin-x.com/groupdiy/albums/userpics/U-4-5-6.JPG (http://www.twin-x.com/groupdiy/albums/userpics/U-4-5-6.JPG) Judging by the color, I would guess that it's the same value as C13 (22pF) -- can anyone verify this?

2. How many watts is R202? This resistor appears much larger than the surface-mount units, but it's difficult to tell if it's more than a 1/4W... http://www.twin-x.com/groupdiy/albums/userpics/Switch___Led.JPG (http://www.twin-x.com/groupdiy/albums/userpics/Switch___Led.JPG)

3. How many volts is C201? I'm assuming 25V or 35V - but the clipping circuit was omitted from the Nite PCB BOM - so, I just wanted to double check.

4. This is question about DC power (rather than the clipping circuit) -- The Nite PCB appears to split the +/-18V DC into 2 sets of rails -- one set powers U1, U2, U3 and the other powers U4, U5, U6. I'm wondering if there is an advantage to this setup versus having all ICs linked to a single +/-18V rail.

Thanks in advance for your help!

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on March 08, 2011, 08:10:35 PM
1. What's the value of C200 and is it necessary? It's not on the schematic, but it appears to connect between pins 5 and 8 of U6... http://www.twin-x.com/groupdiy/albums/userpics/U-4-5-6.JPG (http://www.twin-x.com/groupdiy/albums/userpics/U-4-5-6.JPG) Judging by the color, I would guess that it's the same value as C13 (22pF) -- can anyone verify this?
not verified, but 22pF should fit. Might be omitted, as voltage gain of NE5534 is set for 4.3, so opamp should run stable.

Quote
2. How many watts is R202? This resistor appears much larger than the surface-mount units, but it's difficult to tell if it's more than a 1/4W... http://www.twin-x.com/groupdiy/albums/userpics/Switch___Led.JPG (http://www.twin-x.com/groupdiy/albums/userpics/Switch___Led.JPG)
With +/-18V supply NE5534 might swing +/-16V. Subtract 2 diode drops from 1N4148 rectifier and maybe 2V forward voltage from a red LED / 680R, giving ~19mA current thru LED and a resistor rating of at least 0.24W needed for a worst case continuous constant overload scenario. 1/3W seems sufficient.

Quote
3. How many volts is C201? I'm assuming 25V or 35V - but the clipping circuit was omitted from the Nite PCB BOM - so, I just wanted to double check.
use 35V rating.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: earthsled on March 08, 2011, 08:38:39 PM
Harpo -- thank you so much!

In fact, I've been looking at your spreadsheets and I'm planning to use rotary switches in place of the antilog pots. -- Could you tell me if the calculations from the 3D-EQ_Stepped_Pot.xls will work for the AIR boost control as well as the other frequencies? Also, it seemed like you were recommending 10K for R30 (and R48) when using stepped controls, is this correct?

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on March 08, 2011, 09:25:51 PM
Could you tell me if the calculations from the 3D-EQ_Stepped_Pot.xls will work for the AIR boost control as well as the other frequencies?
simple calc of an inverting opamp stage. Be aware that the 'filter' stages aren't filters but bandwidth limited non-inverting gain stages, so voltage gain doesn't fall below 1.

Quote
Also, it seemed like you were recommending 10K for R30 (and R48) when using stepped controls, is this correct?
Could bring resistive noise down a little, but requires other changes as well. Finaly I modded mine for a non-inverting summing stage, resulting in a totaly different behaviour that was more to my taste.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: earthsled on March 08, 2011, 11:22:33 PM
Quote
simple calc of an inverting opamp stage. Be aware that the 'filter' stages aren't filters but bandwidth limited non-inverting gain stages, so voltage gain doesn't fall below 1.

Hmmm... I'm a little confused what you mean about the voltage gain - the default spreadsheet shows the voltage gain ranging from 0.53 to 1.88 (for -5.5dB to +5.5dB).

I ask about the "air" band because it's only boosting - rather than cut & boost, yet it originally used the 500K reverse-log pot like the other bands. For instance, if I calculate resistances for -10dB to +10dB -- would this translate to a range of 0 to +20dB for the "air" band?

Quote
Could bring resistive noise down a little, but requires other changes as well.

Perhaps it would be best to stay with the original value of 56K2 -- just to keep it simple.

I appreciate your help!

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: earthsled on March 10, 2011, 11:09:21 AM

Would this circuit work for an alternative "pot-to-switch"?
(image attached)

Also - I'm still unsure if a rotary switch will work for the "air" boost control. Has anyone tried this?

Thanks.

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Nobru on March 11, 2011, 04:54:10 AM
Hi there! Is there somebody who would share the schems for this unit with me or any pcb??? this eq can be magic  ;D I would love to play around it.
Thx
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: earthsled on March 11, 2011, 07:07:19 AM
This link should have all you need...
http://www.khstudio.us/EQ3D.htm (http://www.khstudio.us/EQ3D.htm)

Cheers!


Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Nobru on March 11, 2011, 08:54:14 AM
Many thx! ;D
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: earthsled on March 16, 2011, 10:50:23 AM
If anyone is interested in using the "series-string" switch configuration (pictured above), here are my calculated resistance values for an 11-position rotary switch with 2 dB steps (+/- 10 dB for each cut/boost control) --

step 1 to 2 = 36k5
step 2 to 3 = 28k7
step 3 to 4 = 23k2
step 4 to 5 = 18k2
step 5 to 6 = 14k7
step 6 to 7 = 11k5
step 7 to 8 = 9k09
step 8 to 9 = 7k32
step 9 to 10 = 5k76
step 10 to 11 = 4k64
step 11 to sum = 17k8 (replaces R37,39,41,43,45)

Lorlin CK1589 switches...
http://www1.mouser.com/ProductDetail/Lorlin/CK1589/?qs=sGAEpiMZZMsqIr59i2oRcnKZ3G9keN4Q2tT6qRGPIX4= (http://www1.mouser.com/ProductDetail/Lorlin/CK1589/?qs=sGAEpiMZZMsqIr59i2oRcnKZ3G9keN4Q2tT6qRGPIX4=)

From what I understand, using this switch configuration as the air-boost control will result in 1 dB steps -- but Harpo points out that the air-boost technically does not start with 0 dB because it sums with the 2.5k section once it's turned on.

Enjoy!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: ytsestef on March 18, 2011, 10:32:48 AM
If anyone is interested in using the "series-string" switch configuration (pictured above), here are my calculated resistance values for an 11-position rotary switch with 2 dB steps (+/- 10 dB for each cut/boost control) --

step 1 to 2 = 36k5
step 2 to 3 = 28k7
step 3 to 4 = 23k2
step 4 to 5 = 18k2
step 5 to 6 = 14k7
step 6 to 7 = 11k5
step 7 to 8 = 9k09
step 8 to 9 = 7k32
step 9 to 10 = 5k76
step 10 to 11 = 4k64
step 11 to sum = 17k8 (replaces R37,39,41,43,45)

Lorlin CK1589 switches...
http://www1.mouser.com/ProductDetail/Lorlin/CK1589/?qs=sGAEpiMZZMsqIr59i2oRcnKZ3G9keN4Q2tT6qRGPIX4= (http://www1.mouser.com/ProductDetail/Lorlin/CK1589/?qs=sGAEpiMZZMsqIr59i2oRcnKZ3G9keN4Q2tT6qRGPIX4=)

From what I understand, using this switch configuration as the air-boost control will result in 1 dB steps -- but Harpo points out that the air-boost technically does not start with 0 dB because it sums with the 2.5k section once it's turned on.

Enjoy!


Well done, erthsled, thanks for reviving the thread. I have left my build unfinished because of my lack of knowledge on how to make gainswitches work on the air-band. So with the above configuration the switch will be 1dB Boost to 11dB Boost, right?

I also wonder whether it would be possible to make "range switches" for the other bands so that each band would have a switch next to it that switches Rshunt and give less range, but more precise control (for example switch between +/-5dB in 1dB steps and +/-10dB in 2 dB steps)... Could be quite useful, but I don't know if it's possible.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: earthsled on March 18, 2011, 01:28:10 PM
Quote
So with the above configuration the switch will be 1dB Boost to 11dB Boost, right?

To be honest, I'm not sure how many dB it will be. Perhaps Harpo would be kind enough to comment on this matter?

Quote
I also wonder whether it would be possible to make "range switches" for the other bands so that each band would have a switch next to it that switches Rshunt and give less range, but more precise control (for example switch between +/-5dB in 1dB steps and +/-10dB in 2 dB steps)... Could be quite useful, but I don't know if it's possible.

That's a great idea, but it won't work by changing 1 resistance value. Rseries (aka R37,39,41,43,45) sets the maximum boost level, while the total resistance of the pot (or series-string switch) sets the maximum cut. -- If you wanted to get fancy, you could use a switch with 2 decks (each with a different set of resistors) and another switch to select between the decks.


Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: ytsestef on March 18, 2011, 03:37:49 PM
If you wanted to get fancy, you could use a switch with 2 decks (each with a different set of resistors) and another switch to select between the decks.

Yeah, I thought it wouldn't be that simple. Getting dual gand switches for all the bands of each channel and all those weird resistor values doubled would raise the cost much too high over the original revlog pots, plus the overwhelming amount of work to wire all this stuff...  :-\
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: earthsled on March 22, 2011, 10:57:49 AM
Hi all - Does anyone have recommended fuse values for 115VAC and 230VAC operation? Or, better yet, does anyone have a good way to calculate a mains fuse in general for audio equipment and linear power supplies?

I'm planning to use a 25VA toroid transformer with an LM317/337-based power supply to power 2-channels of EQ3d. The PSU will have a voltage selector for both 115VAC and 230VAC input.

khstudio mentioned this in November of 2007...
Quote
If my math is correct, each card should be drawing less that 100ma.
250 - 300ma TOTAL (LEDs & all) should be enough for a stereo unit.

There's some info here, but many of the links are inactive...
http://www.groupdiy.com/index.php?action=printpage;topic=27493.0 (http://www.groupdiy.com/index.php?action=printpage;topic=27493.0)

On a related topic - I noticed the LED for the Bypass circuit uses a 3K3 resistor for current limiting. -- This seems like a high resistance value to me - limiting the LED to about 5mA. Would using the same value be appropriate for a power-indicator LED connected to the +18VDC rail?

Thanks!


Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: ytsestef on March 22, 2011, 11:03:17 AM
I think most transformers pretty much indicate the recommended fuse value and type straight away in their label or specsheet. Mine (50VA) uses T 315mA...
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: earthsled on March 22, 2011, 12:52:04 PM
Funny - I've used toroid transformers from Avel Lindberg, Triad, and Antek, and none of the spec sheets or labels seem to have fuse recommendations - just rated current on the secondaries. ???  Plus, I'd like to choose fuse ratings that will not only protect the transformer, but also the EQ circuit itself - so I'm thinking it would be a lower value than for the transformer.

Out of curiosity, what brand are you using? Do they have specs for 115V vs. 230V operation?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: ytsestef on March 22, 2011, 01:36:40 PM
Funny - I've used toroid transformers from Avel Lindberg, Triad, and Antek, and none of the spec sheets or labels seem to have fuse recommendations - just rated current on the secondaries. ???  Plus, I'd like to choose fuse ratings that will not only protect the transformer, but also the EQ circuit itself - so I'm thinking it would be a lower value than for the transformer.

Out of curiosity, what brand are you using? Do they have specs for 115V vs. 230V operation?

I used to use Multicomp toroidals for the previous projects (gssl,ssl9k), but this time I bought one that is made here (Greece), the brand name is "T. Giatras". It is rated 225V / 50Hz.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: earthsled on March 22, 2011, 09:17:19 PM

I decided to email Triad Magnetics and I'm glad I did. Their engineering manager responded quickly with this information...

"Since the VPT36-690 transformer is rated at 25VA (Volts times Amps), the theoretical input current would be 25VA / 115V = 0.217A or 25VA / 230V = 0.109A.  However, this does not include the magnetizing current or inrush currents – so we generally recommend the fuse be rated at 1.3 to 1.6 times the theoretical input current.  It is very important that a Slow Blow (time delay) fuse be used to allow for inrush currents that exceed the fuse rating to prevent nuisance fuse blowing."

This seems like a very good guideline for fusing the transformer.

Accounting for the actual draw of the DC circuit is considerably more complex -- I'm probably going to just stick with the guidelines above.

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: ytsestef on April 08, 2011, 08:24:00 AM
Finished mine  ;D ;D Thanks a lot everyone!
http://www.groupdiy.com/index.php?topic=43855.0 (http://www.groupdiy.com/index.php?topic=43855.0)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sneakthief on May 07, 2011, 10:42:31 AM
My minimalist user-interface approach:

(http://sneak-thief.com/sneak-eq3d-finished.jpg)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: kato on May 07, 2011, 06:11:35 PM

Love it!

Cool knobs. And different colored LEDs for each band looks cool. Always on I suppose?

Nice job. First minimalist job I've seen that looks inspired minimalist, rather than lazy minimalist. :)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sneakthief on May 07, 2011, 06:58:48 PM
Thanks :)

The LED's for each channel are always on as long as the respective EQ is engaged.

I searched for a while to find decent knobs - I scored them here: http://www.banzaimusic.com/Dial-knob-DKN-113-NUM.html

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: kato on May 07, 2011, 09:30:50 PM

I searched for a while to find decent knobs - I scored them here: http://www.banzaimusic.com/Dial-knob-DKN-113-NUM.html


And they're pretty cheap too. Nice.

When I started in DIY, I thought knobs were the dumbest thing to spend money on. Now, I think it's a nice finishing touch to find some unique knobs that fit the overall look of the piece.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: blue_lu on June 03, 2011, 09:46:48 AM
so is there any way to get my paws on some more pcbs or is it all diy for the pcbs by now...  ???

thanks guys!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: tomcat on June 03, 2011, 03:46:45 PM
Maybe i have a stereo set for you, have to check this weekend.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: leadbreath on June 03, 2011, 04:26:37 PM
hey

im also interested in a pcb if any are left!!??

cheers
mick
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sonicwarrior on June 04, 2011, 04:05:35 PM
Does anyone know where I can get the 100 uH inductors from?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: tomcat on June 04, 2011, 04:55:11 PM
Mouser 70-IR4-J-100 should work
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: seavote on June 04, 2011, 06:09:17 PM
looks like a very self "etchable" PCB . was ther ever artwork available for this project
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: statzern on June 05, 2011, 01:41:35 AM
I have also been looking for some pcbs for a long time for this project! An etch file would be enough, though I would like to buy them if I can.

If anybody has any boards to spare: [email protected]

Thanks!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sneakthief on June 05, 2011, 10:33:23 AM
Is the PCB overlay file from here usable?

http://www.khstudio.us/EQ3D.htm

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: ytsestef on June 05, 2011, 04:19:40 PM
I don't think so, you need only the traces and the pads.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Nele on June 05, 2011, 04:33:15 PM
if you can work with illustrator it's pretty easy to edit the pdf to have only the traces..
I would post it here but I don't know if Peter and Kevin are ok with that..
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on June 06, 2011, 03:29:03 AM
Hi all

Seems to be a bit of demand, so I will put up the track pattern over the next few days.

Peter
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: detonator on June 06, 2011, 12:12:04 PM
Please check the groups gmail account
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bieckmusic on June 08, 2011, 09:32:32 AM
I'd love the self etch files or boards!!!   ;D ;D ;D
this looks like an awesome project!
major thanks to it's designers 8-)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on June 08, 2011, 10:33:42 AM
Detonator

Thanks for putting up those files, all who want to do their own boards the track pattern is there.

Please no mass production (other than for your own Personal purposes) using my PCB design.

Peter
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: detonator on June 08, 2011, 10:39:26 AM
Detonator
Thanks for putting up those files, all who want to do their own boards the track pattern is there.
Please no mass production (other than for your own Personal purposes) using my PCB design.
Peter
These files were sent only for educational or private purposes. Anything else is prohibited.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: mitsos on June 08, 2011, 03:01:38 PM
Not sure if people have seen this, but looks like they're back in production for the 500 rack:

http://maagaudio.com/index.php?main_page=products_all&zenid=0ff1ba91d40bae5136464d6c596a2cad
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sonicwarrior on June 09, 2011, 03:51:09 PM
Are 16 mm Alpha pots ok? I've heard they are not as good as the 24 mm ones but until now I've only used the bigger ones myself.
500K Rev Logs are not available as 24 mm Alphas.
The source is Banzai:
http://www.banzaimusic.com/Alpha-16mm-FS-500k-REV-log.html
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: tomcat on June 09, 2011, 07:38:46 PM
Well, you have no center detend (einrastende Mittelstellung) on the Alphas!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sonicwarrior on June 10, 2011, 01:33:02 PM
Damn, well then I have to buy the ones from Audiomaintenance.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bieckmusic on June 11, 2011, 05:37:41 PM
does anyone have a mouser or digi-key b.o.m?  having trouble figuring out which parts will fit...  Also, is there a self-etch image for the power supply too.  Thank you for posting the traces for the main PCB!!

thanks to everyone
 :)   greg
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sonicwarrior on June 12, 2011, 06:52:00 AM
I have attached the BOM I use(d). It has the spacings of the capacitors which makes it easy to source them at any parts supplier.

Edit: There are only three 20K resistors!!! The R26 is only mentionend above the red marked R26 because there are two resistors called R26 on the board.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bieckmusic on June 12, 2011, 06:28:29 PM
thanks, I'm getting ready to make my online B.O.M  8-)   I didn't understand the pin spacing.  the b.o.m. says 5/7.5/10mm.  do you mind explaining what that spacing refers to?  On the mouser site it seems you can only pick one number like 5 mm or so on?   Sorry for the questions!! 

best, Greg
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: signalflow on June 12, 2011, 06:44:16 PM
thanks, I'm getting ready to make my online B.O.M  8-)   I didn't understand the pin spacing.  the b.o.m. says 5/7.5/10mm.  do you mind explaining what that spacing refers to?  On the mouser site it seems you can only pick one number like 5 mm or so on?   Sorry for the questions!! 

best, Greg


That means you can use a 5mm or a 7.5mm or a 10mm spaced capacitor for those parts on the board.  Take a look at the footprint on the board for the specific parts and you will see what I'm talking about.

-Casey
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bieckmusic on June 12, 2011, 08:28:50 PM
thanks Casey!!  so simple I missed it 8-)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: signalflow on June 12, 2011, 09:52:25 PM
No problem.

-Casey
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: tomcat on July 31, 2011, 08:34:59 PM
What value did you use on R9? The BOM says it should  be 64R9 or 64R. Both i cannot get here, i can do some serializing of values to come close. How close should it be?

22R +43R = 65R should be fine (1%) !? Otherwise i have to go the 20+20+24 route.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sonicwarrior on August 01, 2011, 01:43:01 PM
Sent you an email.  :)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bieckmusic on August 05, 2011, 10:46:14 AM
Hi everyone!    :) After several months I'm ready to order my parts and the press and peel blue paper to make the self etch boards. But, I was wondering if anyone had the self etch file for the power supply board?  Am I correct, you need 3 pcbs the two eq channels and a power board.  I got the eq file off the group email buy can't find the power supply file. 

I've never done a self etch so I'm a little nervous.  Sorry for my questions, this eq looks awesome!!

Greg
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: ytsestef on August 05, 2011, 11:11:03 AM
I used the SSL9k PSU. Any +/-18V will do ;)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: choolder on August 25, 2011, 03:26:26 PM
Hi everyone,

This is my first DIY project and I'm struggling a little bit with finding all the right parts.

Would this rotary switch work for selecting the high frequenties?
http://www.audiomaintenance.com/acatalog/LO-03-002_extended_info.html

And I would like to replace the other switches with stepped pots, with 11 steps or even 21 steps. Anybody has a link for this kind of switch?

Thanks in advance guys :-)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: earthsled on August 26, 2011, 09:18:23 PM
Hi there,

I used Lorlin CK1459 for the frequency selector, and Lorlin CK1589 for 11-step cut/boost switches. Both should be available from Mouser in the U.S. -- They are U.K.-made switches so there must be a source for them there too.

The one you have a link to on AML will do fine for frequency select -- it's the PCB pin version so the tabs are a bit small for soldering wires, but it will work.

More info can be found here: http://www.lorlin.co.uk/PDF/CK.pdf (http://www.lorlin.co.uk/PDF/CK.pdf)

Hope this helps!


Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: nielsk on August 26, 2011, 10:00:26 PM
Has anyone posted response plots of their build? I can't find any, I recently ran Smaart on mine & see pretty much no cut, only boost on all the bands...
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: earthsled on August 27, 2011, 12:00:23 PM
I ran some sweeps last night with FuzzMeasure --- I'm getting boosts and cuts, but the dB level seems to be more subtle than intended. I'm using stepped switches rather than the pots, so the error may be in my math. Strangely, the Air band on my unit seems to be working as planned.

Attached are the results of sweeps I ran through each band "maxed out" at -10 and +10...
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: nielsk on August 27, 2011, 03:19:13 PM
Interesting. I can't see what could cause this behavior on mine...
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: earthsled on August 27, 2011, 06:36:14 PM
Are you using stepped switches or the reverse-log pots? From my understanding, the total value of the pot/switch (resistance for RV36,38,40,42,44 will set your maximum cut, while the value of R37,39,41,43,45 will set the max boost. Can you tell how many dB of boost you're getting?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bieckmusic on September 05, 2011, 12:48:16 PM
For the power supply, will the mnats VARIABLE + PHANTOM POWER SUPPLY work instead of the SSL9k?  Also, Any idea which transformer to use.  I usually use avel-lindberg torroidal in my other projects and loved it!!  I was thinking using this one from avel-lindberg Y236006, it's 15VA and secondaries are 25v but the mnats board says 24vac in.

Also, I did searches and couldn't find a cheap source of the copper board to use for self etch with press and peel blue.  The cheapest I found was $15 for 9"x12".  If any one has a great source of self-etch board and a great price that would be awesome!!!

any thoughts would be greatly appreciated!! 

thanks!!
Greg
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: earthsled on September 05, 2011, 11:16:11 PM
The mnats V+PPS probably isn't the best choice, it only provides +24V and +48V. You'll need both -18V and +18V rails. I used the JLM ACDC and omitted the phantom power. I'm having trouble finding info on the SSL 9K, but it will probably work if it provides positive and negative voltage rails. Your transformer will ideally have 18V secondaries - and don't skimp on the VA. The A-L Y236104 is a good choice, or Mouser has this one... 553-VPT36-690

Sorry, I can't help with the copper board - I'm not a self-etcher.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bieckmusic on September 06, 2011, 02:53:07 PM
Thanks for that Earthsled!

I was able to find a .pdf with the BOM and schematic for the SSL9k.  Also, they're were several forums in the lab, including one topic just dedicated to the power supply.  I have located almost all of the parts and then thought maybe the mnats would be better.  But, I'll stick with the ssl 9k power supply.

Have a great day!
greg
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: earthsled on September 27, 2011, 06:01:29 PM
nielsk: I've just worked up a second version of my EQ3D build. This time I used potentiometer/rotary switch resistance values that were very close to the original spec. I thought you'd be interested to know that I too am seeing a "boost" that is disproportionately large compared to the "cut" with this config. For instance, my 650Hz band will boost about 14.5dB while it only cuts about 4dB. This seems very similar to what you were experiencing. Attached are graphs...

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on September 27, 2011, 10:37:45 PM
nielsk: I've just worked up a second version of my EQ3D build. This time I used potentiometer/rotary switch resistance values that were very close to the original spec. I thought you'd be interested to know that I too am seeing a "boost" that is disproportionately large compared to the "cut" with this config. For instance, my 650Hz band will boost about 14.5dB while it only cuts about 4dB. This seems very similar to what you were experiencing. Attached are graphs...

Did you use this document?

(change the extension of the document from DOC to XLS , as it is an excel file)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: earthsled on September 27, 2011, 11:39:26 PM
I used the "stepped-pot" rotary switch version...
www.hausverwaltung-heger.de/al_leck_trick/3D-EQ_PotTweaking_2.xls (http://www.hausverwaltung-heger.de/al_leck_trick/3D-EQ_PotTweaking_2.xls)
...and modified it for a series-string config. but, essentially, yes.

Using 1% value resistors my switches came out to be...
RV total = 553300 ohms
RV center = 50300 ohms
R series = 5620 ohms

Harpo suggests that the bands of the EQ actually interact with each other...
"Simply speaking, boost will work within parts/rail voltages limits; cut to more than -~5dB will work, if adjectant bands levels are dialed in for cut as well."

Perhaps this response is what the circuit was designed to do?
Anyone have sweeps for the original Nightpro unit???
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on October 24, 2011, 07:41:31 PM
I started a feeler thread on the Black Market for a new batch of Night Eq PCB from Peter.

If anyone would like some PCBs please visit this thread:

http://www.groupdiy.com/index.php?topic=46244.msg580026#msg580026
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on October 25, 2011, 11:24:17 AM
Night EQ Project - Docs

SCHEMATIC

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on October 25, 2011, 11:27:53 AM
Night EQ Project - Docs

PARTS LIST
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on October 25, 2011, 11:28:12 AM
Night EQ Project - Docs

PARTS LIST 2
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on October 25, 2011, 11:28:57 AM
Night EQ Project - Docs

PCB Overlay
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on October 25, 2011, 02:15:05 PM
As for Pots with centre ident you can get them here:

http://www.audiomaintenance.com/acatalog/om-01-066_extended_info.html
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bieckmusic on November 08, 2011, 10:10:01 AM
Hello again friends,   :)

is this 5534
http://www.mouser.com/ProductDetail/Texas-Instruments/NE5534AP/?qs=sGAEpiMZZMtCHixnSjNA6CumnoLUElGjy%2feFGFMqIic%3d

 compatible for the eq3d project.  I'm not sure???  Does anyone have a good source for the 5534s?  I found the JRC 5532's are available inexpensively fortunately!!

thanks :)  Making progress, got my resistors stuffed on my home etched boards...

best, Greg
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: earthsled on November 08, 2011, 10:20:02 AM
I used the JRCs in mine. Mouser has them... 513-NJM5532D and 513-NJM5534D ...I think JRC 5532s were used in the original version, not sure about the 5534s (see attached)...
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bieckmusic on November 08, 2011, 10:45:00 AM
Awesome, thanks!  I just ordered them  :)

Cool, I've never seen a picture of the original unit.  Thanks for the help!

 :)
Greg
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Davo on November 15, 2011, 10:12:42 AM
......
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bieckmusic on December 12, 2011, 10:13:44 PM
It's done, and it sounds AMAZING!!!  :) :) :) Great frequencies...  What a great project, big thanks to Kevin and everyone who contributed to this project.  I had to switch my jumpers and check solder joints but other than that this was a pretty straight forward project.  The most time I spent was researching and ordering parts.  I used an ssl 9k power supply for the project.

Also, this was the first time I ever did a self-etch which was interesting... 

I've attached a photo.  I'm going to make some graphics for the front panel at a later date. 
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bieckmusic on December 12, 2011, 10:16:57 PM
one more picture....

Here's the inside of the project.  I'm going to clean things up later, but it's very quiet and smooth sounding.   :)

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Rellister on December 13, 2011, 07:41:05 AM
Excellent work bieck :D
How did you end up series-resistor-wise?
Just BOM values or calculated?



Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bieckmusic on December 13, 2011, 08:55:27 AM
Hi Thank You Rellister!   :)

I used the BOM values for all of the resistors.  I just followed everything as close as I could, including all of the inductors, etc...

All pots neutralized sounds almost perfectly flat, I'd like to scope it to check there might be a slight bass decrease, I can't tell.  All the pots from audio maintenence measured around 50k and 60k at center point so I decided not to mess with swapping resistors values. 


 :)

Greg
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: earthsled on December 31, 2011, 04:50:32 PM
Hi all --

I'm noticing my peak indicators seem to light up at signal levels well below audible distortion. I'm feeding the EQ a 1K tone at about 0.9V RMS and the LEDs begin to glow. Does this seem like the right level? Could the peak circuit me modified to have a trim-pot adjustment?

Thanks!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on January 01, 2012, 10:52:23 AM
make R201 a rheostat to dial in less sensivity. Voltage gain of this inverting stage is R201/R200.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: wave on January 07, 2012, 10:37:08 PM
Hi Thank You Rellister!   :)

I used the BOM values for all of the resistors.  I just followed everything as close as I could, including all of the inductors, etc...

All pots neutralized sounds almost perfectly flat, I'd like to scope it to check there might be a slight bass decrease, I can't tell.  All the pots from audio maintenence measured around 50k and 60k at center point so I decided not to mess with swapping resistors values. 


 :)

Greg

Greg,
Do you have a Mouser cart for this project you can share?

Wave
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bieckmusic on January 08, 2012, 12:58:20 PM
Hi Wave,

Sure no problem.  I need to edit a few things on there and consolidate two mouser orders into 1, then I can pass it on to you.
best,
greg
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: wave on January 08, 2012, 02:49:42 PM
Hi Wave,

Sure no problem.  I need to edit a few things on there and consolidate two mouser orders into 1, then I can pass it on to you.
best,
greg

You totally rock!!

EDIT: My 100th post!!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bieckmusic on January 08, 2012, 04:36:02 PM
Here's what I used for my EQ3d project.  I preface this by saying, it's not guaranteed or a professional BOM in any way.  It's just what I used for my eq  8-)

Also, a few of the power supply electrolytic caps I used are too tall for a 1 rack space eq. 

The parts listed here are for the SSL 9k power supply which is what I used to power the project.  I built my unit as a self-etch and didn't have access to the standard EQ3d power supply board.  If you are not using the SSL 9k power supply you will have to ignore this BOM.
There are two sets of inductors on the BOM, I'm not sure which ones I used, probably the cheaper ones  ;D

BOM for 1 channel EQ (1 board, for stereo order 2)
http://www.mouser.com:80/ProjectManager/ProjectDetail.aspx?AccessID=332e141d2d

op amps for 2 boards
http://www.mouser.com:80/ProjectManager/ProjectDetail.aspx?AccessID=01f16ca11a

SSL power supply
http://www.mouser.com:80/ProjectManager/ProjectDetail.aspx?AccessID=370e48c7ce


Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: earthsled on January 13, 2012, 11:10:53 PM
make R201 a rheostat to dial in less sensivity. Voltage gain of this inverting stage is R201/R200.

Ah! I think I found the issue with my clipping indicators... The schematic shows R200 with a value of 4K46. From the attached pic, it looks like the value should have been 46K4 instead.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bieckmusic on January 29, 2012, 01:28:09 PM
Hi earthsled,

How did you go about making your clipping indicator.  Did you breadboard it just by referencing the schematic??  Or did you design a circuit board and etch it?  I'm thinking of trying to build one by referencing the schematic just to develop some skills...    Thanks, hope you don't mind my asking...

have a great day!

best,
greg
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: earthsled on January 29, 2012, 11:23:30 PM

I made my own PCB for the EQ and included the clipping circuit. For this, I referenced the schematic, original layout, etc. I didn't etch -- I ordered the boards from Advanced Circuits (check out their "BareBones" and "$33 each" deals). http://www.4pcb.com/index.php?load=content&page_id=129 (http://www.4pcb.com/index.php?load=content&page_id=129)

If you're on a Mac - I'd also recommend OsmondCocoa for PCB design software. http://www.osmondpcb.com/ (http://www.osmondpcb.com/)

You could totally build the circuit on a breadboard though. Like you said, it's good practice!

Cheers!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bieckmusic on January 30, 2012, 07:01:06 AM
Awesome, thanks for the tip!   :) :) :)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: e.oelberg on February 14, 2012, 12:18:45 PM
I just finished my nite eq, with some little changes different opamps and different balancing amp.
Noisefloor -101dB RMS eq switched on

Nicholas
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: e.oelberg on February 15, 2012, 01:51:37 PM
btw I used 50 k rev log pots... easier to find and less resistor noise than 500k you have to change all 5K62 resistors to 562  also the 56K2 resistor have to be replaced with 5k62. sound is exactly the same, just maybe less noise.

 ;)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: e.oelberg on February 16, 2012, 11:13:19 AM
btw I used 50 k rev log pots... easier to find and less resistor noise than 500k you have to change all 5K62 resistors to 562  also the 56K2 resistor have to be replaced with 5k62. sound is exactly the same, just maybe less noise.

 ;)

I just measured it. Now I have -106 dB rms ... so it makes a difference
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on February 16, 2012, 12:37:31 PM
No Center Detent-Ident on the pots makes this project much less interesting.

The Pots with the right value and center detent are easily available from audiomaintenence , theres no reason to use any other value.


btw I used 50 k rev log pots... easier to find and less resistor noise than 500k you have to change all 5K62 resistors to 562  also the 56K2 resistor have to be replaced with 5k62. sound is exactly the same, just maybe less noise.

 ;)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: e.oelberg on February 16, 2012, 03:17:53 PM
level matching is not that easy with that project and the curve it did with the center ident pots looked like a snake,
I prefer having no ident, and check visually for center. And the benefit of 50k vs 500k resistor noise is also worth
to consider. I had one board with 50k pots and one with 500k pots and I didn't hear a difference, just the noise floor is lower.
 I might work on a pcb with lorlin switches for a stepped version.

I have a set of 12 audiomaintanace 500k rev log pots center ident for sale !
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on February 20, 2012, 11:45:36 AM
level matching is not that easy with that project and the curve it did with the center ident pots looked like a snake,
I prefer having no ident, and check visually for center. And the benefit of 50k vs 500k resistor noise is also worth
to consider. I had one board with 50k pots and one with 500k pots and I didn't hear a difference, just the noise floor is lower.
 I might work on a pcb with lorlin switches for a stepped version.

I have a set of 12 audiomaintanace 500k rev log pots center ident for sale !

yes Level matching is quite easy, just use the excel file attached, and actually the level matching will always be a problem even if you use center ident or not.

Have a center ident pots and using the excel file to calculate the resistors to attain level matching is just a matter of making it as best as possible instead of making a poor build.

I would like to buy the pots from you,
send me a pm

Thanks

(delete ".doc" from the extension, this is a RAR file)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: whomper on February 25, 2012, 12:39:57 AM
Hi,

Is there a front panel file that could be shared? Am working now to design my front panel and would be happy to use an already made one.

Thanks,

Whomper
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Rellister on February 25, 2012, 12:30:13 PM
I think Purusha still has cases, If that´s an option for you.

Cheers

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Rellister on February 26, 2012, 06:49:03 PM
Hi,
Can anyone help me understand something strange;
I tied my XLR pin 1´s to star ground. When I hook up the boards to the PSU, the neg. rail drops down to about -1,5V and the toroid makes a buzzing noise. It seems like the neg. rail get shorted somehow and the toroid can´t handle it. When I remove the grounding from the xlr´s everything goes back to normal, all voltages measure as they should.
Haven´t tried passing sound through it yet.
This might be something trivial, I´m not experienced enough to figure it out, but maybe someone who understands the circuit better than me can explain it?
All help appreciated!

Thanks
Rune


Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: whomper on February 26, 2012, 09:10:15 PM
I think Purusha still has cases, If that´s an option for you.

Cheers

Thanks, he does seem to offer a case plus front panel, but due to weight,vthismwillvcost me a fortune with shipping.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Rellister on March 06, 2012, 10:34:42 AM
Hi,
Can anyone help me understand something strange;
I tied my XLR pin 1´s to star ground. When I hook up the boards to the PSU, the neg. rail drops down to about -1,5V and the toroid makes a buzzing noise. It seems like the neg. rail get shorted somehow and the toroid can´t handle it. When I remove the grounding from the xlr´s everything goes back to normal, all voltages measure as they should.
Haven´t tried passing sound through it yet.
This might be something trivial, I´m not experienced enough to figure it out, but maybe someone who understands the circuit better than me can explain it?
All help appreciated!

Thanks
Rune

bump...

Checked all my opamps, they seem fine, measure +/- 6Mohm between pins 4&8.
Res. between +/- rails & opamp pins also fine, 22ohm.
Resistance between +/- rails seems a bit low, about 1,5-2K? Beats me.
Using a mnats PSU with regulators mounted to chassis, but with mica insulators. Could the issue be here anyway?
I get continuity from regs to chassis ground, is that the issue? Still, voltages are fine at psu output.

Voltages at opamp pins are correct. +/- 18V here.
The issue is, there seem to be some voltage potential at PSU ground, and if i tie it to chassis(star) ground there is a short.
I´m a afraid to damage someting else if I hook it up, so I´d like to get to the bottom of this first!

Cheers
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on March 06, 2012, 01:49:18 PM
Quote
The issue is, there seem to be some voltage potential at PSU ground, and if i tie it to chassis(star) ground there is a short.

Could just be spurious AC. Try using a 10R resistor to tie the PSU ground to chassis, if there is a problem, that will burn out or the fuse will
blow first.

Peter

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on March 06, 2012, 03:21:40 PM
Using a mnats PSU with regulators mounted to chassis, but with mica insulators. Could the issue be here anyway?
I get continuity from regs to chassis ground, is that the issue? Still, voltages are fine at psu output.
There might be a sharp edge at the drill hole pushing thru your mica insulator on the negative rail regulator (or you also missed to use insulation washers). Regulators heatsinks are internally connected to the regulators center pin, being at neg.raw DC input voltage for the 337 and pos.regulated DC output voltage for the 317. There shouldn't be continuity but infinity resistance between chassis and both regulators heat sinks.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Rellister on March 06, 2012, 05:49:26 PM
There might be a sharp edge at the drill hole pushing thru your mica insulator on the negative rail regulator (or you also missed to use insulation washers). Regulators heatsinks are internally connected to the regulators center pin, being at neg.raw DC input voltage for the 337 and pos.regulated DC output voltage for the 317. There shouldn't be continuity but infinity resistance between chassis and both regulators heat sinks.

That´s it. A sharp edge from my drill hole was shorting the neg. regulator to chassis. Just filed the edge down a bit and problem solved. Guess one have to be more careful when insulating regs to chassis. Lesson learned!

Time for some eq´ing!

Thanks!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: cjs2k on March 11, 2012, 01:25:05 AM
Check these out.

 http://www.pedalpartsplus.com/mm5/merchant.mvc?Screen=PROD&Store_Code=PPP&Product_Code=7524&Category_Code=Pot16R
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: hitchhiker on March 19, 2012, 12:15:47 PM
Great price there! Anyone know the price of the center detent pots from Audiomaintenence ?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Zachery on March 21, 2012, 04:49:49 AM
Sorry I am a DIY noob and just have a few questions, if anyone can help me. I'm making my first PCB etch just for this board, and the question is, is the PCB overlay on page 41 of this thread, the PCB overlay for the etch? And if so, how does the red lines not get in the way of the regular lines? Can anyone explain this to me or how I avoid the red lines when making the etch?

Second, can someone point me to the direction for instructions on the psu??
Like a pcb overlay or a psu I can use from another project?

Any help would greatly be appreciated, I'm still teaching myself a lot of these processes.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Timothytitus88 on March 21, 2012, 08:10:40 AM
I don't think there is the self etch artwork for this project available - someone correct me if I am wrong, I would love to make a couple of these!

The PCB overlay is looking from the top of the board (to show where all of the components go) - the grey tracks would need to be mirrored to be the right way around, and yes the red lines are in the way anyway.

If you are etching, perhaps the audioX studer eq would be a better first project, and the PCB artwork is available (called copper mirror) - http://www.groupdiy.com/index.php?topic=33996.0

Cheers,

Tim
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bieckmusic on March 21, 2012, 12:49:43 PM
Hi Zachery,

If you read back through the thread there is self-etch info posted, or at least there was.  It was posted on the group internet account.

I used the night eq for my first self-etch and it's a pretty simple circuit to build.  The traces are far enough apart on the circuit board that my sloppy soldering was not a problem.   :)  I found it actually easier than several other kits.  I used the ssl 9k pre power supply which works perfectly, and there is a self etch available for it on the group diy site.  It's an amazing sounding eq.

best,
Greg
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Zachery on March 21, 2012, 01:30:38 PM
Thank you guys so much for your quick replies, that what I was talking about self etch artwork just didn't know the terminology. I figured the pcb overlay was just for placement of components, thats why I wanted to ask. I'll have to look through this thread and other sites for the self etch artwork because I have read numerous times is was an easy first self etch and I've always dreamt about one of these.

Thank you very much, I've read about people using the Ssl power supply for this, and. I just wanted to clarify that before I went forward. If I find the self etch for this project I'll repost, for easier access. It seems that is the only info missing on page 41.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: WNStudios on March 21, 2012, 02:10:51 PM
I've been looking like a madman and the files should be on the Gmail account, but as that one is closed it doesnt seem like the files are anywhere to be found.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on March 21, 2012, 03:37:54 PM
Hi all

Files placed on Twin-x, check here:

http://twin-x.com/groupdiy/thumbnails.php?album=485

Peter
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Timothytitus88 on March 21, 2012, 07:29:29 PM
Fantastic!

Thanks Peter.

Time to pull out the chemicals and source the pots!

Tim
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: wave on March 21, 2012, 07:47:18 PM
Fantastic!

Thanks Peter.

Time to pull out the chemicals and source the pots!

Tim
Speaking of the pots, I can't get to the page on audiomaintenece anymore.

Dave
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Zachery on March 22, 2012, 02:03:30 AM
Thank you so much! You're a life saver Peter! I'll post a detailed process in a thread when I start!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on March 23, 2012, 08:39:21 AM
Fantastic!

Thanks Peter.

Time to pull out the chemicals and source the pots!

Tim
Speaking of the pots, I can't get to the page on audiomaintenece anymore.

Dave

Audiomaintenance probably run out of stock,
I contacted Colin to see if they were placing a new order to Omeg soon.

It's critical in this project that you have Center Ident pots for all the Frequencies , except the Air, otherwise you will not be able to have a zero boost in the middle and also Left and Right channels will be way off.


Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: wave on March 23, 2012, 01:36:49 PM
Fantastic!

Thanks Peter.

Time to pull out the chemicals and source the pots!

Tim
Speaking of the pots, I can't get to the page on audiomaintenece anymore.

Dave

Audiomaintenance probably run out of stock,
I contacted Colin so see if they were placing a new order to Omeg soon.

It's critical in this project that you have Center Ident pots for all the Frequencies , except the Air, otherwise you will not be able to have a zero boots in the middle and also Left and Right channels will be way off.

Thanks!

Dave
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: detonator on March 24, 2012, 07:04:13 PM
Another source for pots http://www.banzaimusic.com/Alpha-16mm-FS-500k-REV-log.html (http://www.banzaimusic.com/Alpha-16mm-FS-500k-REV-log.html)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: spase on March 24, 2012, 08:48:58 PM
Another source for pots http://www.banzaimusic.com/Alpha-16mm-FS-500k-REV-log.html (http://www.banzaimusic.com/Alpha-16mm-FS-500k-REV-log.html)

but this ones are not center ideneted,but they can work.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: cstella on March 25, 2012, 01:06:25 PM
I also asked Colin about when the pots would be available again and he said mid April.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on March 25, 2012, 04:36:40 PM
I also asked Colin about when the pots would be available again and he said mid April.

Thats really cool
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sedit1 on April 08, 2012, 01:17:17 AM
Hi guys!

This is my first eq build that I'm doing with stepped switches and I read the whole thread and didn't have a clear answer.
Can you use harpos xls sheet to calculate the air band resistors? Afterall it's the same it's the same value if you use pots?

Thanks!

Edit...Answer to my own question: Seems to be working just fine :)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: supiarmando on April 11, 2012, 12:22:22 PM
Are there still some PCBs available? I would like to build a stereo version!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sedit1 on April 14, 2012, 12:23:36 PM
Hi, I need some help  :)

I have some gain problems in my unit, I cheked the previous posts concerning about gainloss but didn't help.

So when the unit is bypassed the gain is normal but when I put the eq on the gain drops about 10db's, it's the same with both channels and it doesnt matter if i use balanced or unbalanced jumpers.

I have a stepped version using harpos xls values and the only thing different is that I'm using green pre psu with +-15v rails.

I just have cheked all my caps, they are the right value no errors there, also cheked solder bridges, all fine.
And measured all the ic pins and +-15v were on the right spots, I'm using JRC 5532d/5534d's


Do you have any pointers that I should check?

Edit...I also checked all the resistors with colour charts, all fine there and measured the ic:s hey were fine also.

So I'm litlebit confused and I was thinking that did I made some mistake using the rotary switches? I used Harpos xls v1 to calculate the pot values(no parallel resistor), I used 11 step lorlins and the center is normal 56k2 the rest of the build is done exactly by the bom. Did I made somekind of mistake, do I need to change some other parts to make the switched version to work normally?

Thanks!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: leafcutter on April 15, 2012, 03:07:54 PM
Quick sanity check:

Do you think that this: http://uk.farnell.com/multicomp/mcta060-18/transformer-60va-2-x-18v/dp/9530444

would be ok to power 4 channels of Nite Eq via Green PSU board?

also anyone know if any of those Audio Maintenance switches are the right pin spacing for the Nite Eq board?

Cheers,

John.

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on April 16, 2012, 02:20:43 AM
John

That transformer will work, but is a lot bigger than you actually need. A 30VA 2 x 15v transformer will work just as well and be a tad cheaper.

This one would be good: MCTA030/15

http://www.farnell.com/datasheets/79607.pdf

Peter
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: leafcutter on April 16, 2012, 04:05:05 AM
Thanks Peter,

Is the Green PSU shown here set up for +/- 15 or +/- 18. Am I right in thinking that to get +/- 18 I'd need a 2 x 18v transformer?

Cheers,

John.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on April 16, 2012, 05:20:21 AM
With a 2 x 18v trasnformer, the rectified voltage will be +-((18 x 1.414) - 1.4v) = +-24v.

With a 2 x 15v trasnformer, the rectified voltage will be +-((15 x 1.414) - 1.4v) = +-19.8v

Regulators need 3v to work properly, so the 2 x 18v transformer is good for +-18v.

Having done these calcs, I dont like running projects at +-18v. The gain is dynamic range  is in the region of 2dB, and most times I have used 17.5v  on the projects, something has gone up in smoke..... This is using max +-18v opamps like the TL074



Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sedit1 on April 17, 2012, 12:30:39 PM
Nobody?  :(

Could it be the Ic's? They all measured 40/50k between pins 4-8/7.

First I doubted cap values but they are correct. What could possibly cause the gainloss? Just cheked the gainloss is 14db's. Otherwise everything works great and the sound is good.


Hi, I need some help  :)

I have some gain problems in my unit, I cheked the previous posts concerning about gainloss but didn't help.

So when the unit is bypassed the gain is normal but when I put the eq on the gain drops about 10db's, it's the same with both channels and it doesnt matter if i use balanced or unbalanced jumpers.

I have a stepped version using harpos xls values and the only thing different is that I'm using green pre psu with +-15v rails.

I just have cheked all my caps, they are the right value no errors there, also cheked solder bridges, all fine.
And measured all the ic pins and +-15v were on the right spots, I'm using JRC 5532d/5534d's


Do you have any pointers that I should check?

Edit...I also checked all the resistors with colour charts, all fine there and measured the ic:s hey were fine also.

So I'm litlebit confused and I was thinking that did I made some mistake using the rotary switches? I used Harpos xls v1 to calculate the pot values(no parallel resistor), I used 11 step lorlins and the center is normal 56k2 the rest of the build is done exactly by the bom. Did I made somekind of mistake, do I need to change some other parts to make the switched version to work normally?

Thanks!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Hank Dussen on April 17, 2012, 03:25:20 PM
Hi, I need some help  :)

I have some gain problems in my unit, I cheked the previous posts concerning about gainloss but didn't help.

So when the unit is bypassed the gain is normal but when I put the eq on the gain drops about 10db's, it's the same with both channels and it doesnt matter if i use balanced or unbalanced jumpers.

I have a stepped version using harpos xls values and the only thing different is that I'm using green pre psu with +-15v rails.

I just have cheked all my caps, they are the right value no errors there, also cheked solder bridges, all fine.
And measured all the ic pins and +-15v were on the right spots, I'm using JRC 5532d/5534d's


Do you have any pointers that I should check?

Edit...I also checked all the resistors with colour charts, all fine there and measured the ic:s hey were fine also.

So I'm litlebit confused and I was thinking that did I made some mistake using the rotary switches? I used Harpos xls v1 to calculate the pot values(no parallel resistor), I used 11 step lorlins and the center is normal 56k2 the rest of the build is done exactly by the bom. Did I made somekind of mistake, do I need to change some other parts to make the switched version to work normally?

Thanks!


If everything is working fine and it's just a 14dB gain loss it's more likely there's a wrong resistor somewhere. Double check the resitors around U4 and U5.
Sometimes reading color-codes can be really tricky. White looking like grey etc...
The color-code, for example, of a 10K reistor looks really alike 100K...
Try measuring the resistors. Though it might not always read the correct value when there's another resistor or cap in parallel but it could give you a clue...
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sedit1 on April 18, 2012, 11:33:06 AM



If everything is working fine and it's just a 14dB gain loss it's more likely there's a wrong resistor somewhere. Double check the resitors around U4 and U5.
Sometimes reading color-codes can be really tricky. White looking like grey etc...
The color-code, for example, of a 10K reistor looks really alike 100K...
Try measuring the resistors. Though it might not always read the correct value when there's another resistor or cap in parallel but it could give you a clue...
[/quote]

Thanks good advice!
I triple cheked the resistors but nothing. Everything correct. Here's two pictures if you can see something that I don't.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sedit1 on April 18, 2012, 11:34:10 AM
Second. The pcb shot.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sedit1 on April 20, 2012, 01:16:09 AM
Thanks good advice!
I triple cheked the resistors but nothing. Everything correct. Here's two pictures if you can see something that I don't.

Any more pointers?
Getting really confused, because I have checked all the resistor/cap values many times and I don't think it's soldering error because the two channels are identical and behaving the same. Can a broken opamp cause something like this?

Or can it be something to do with the rotary switches? The switch values are about 660k/switch. And when I measures the bypass resistor, when unit bypassed it showed about 15k resistance and when eq on it was 56k2.

Please help me  :)

Thanks!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on April 20, 2012, 10:08:21 AM
Sedit1

Did you actually measure the resistors suggested above? I know I have a batch of 1% resistors where the 100k looks exactly like a 10k, i.e. the red stripe looks like an orange stripe and vice versa......

Peter
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sedit1 on April 20, 2012, 10:59:45 AM
Sedit1

Did you actually measure the resistors suggested above? I know I have a batch of 1% resistors where the 100k looks exactly like a 10k, i.e. the red stripe looks like an orange stripe and vice versa......

Peter

Thanks Peter, yes I measured them twice and were hoping that that would have been the solution because thats the most obvious, but no.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on April 20, 2012, 09:36:37 PM
Sedit1

Did you actually measure the resistors suggested above? I know I have a batch of 1% resistors where the 100k looks exactly like a 10k, i.e. the red stripe looks like an orange stripe and vice versa......

Peter

Thanks Peter, yes I measured them twice and were hoping that that would have been the solution because thats the most obvious, but no.

Hard to understand, its strange that its the same in both channels.

You should do a signal tracer cable, and follow the schematic, tracing the circuit and figure out at which point does the sound drop. 
I would also guess its a wrong resistor value on the same place in both channels
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sedit1 on April 21, 2012, 12:48:40 AM
Sedit1

Did you actually measure the resistors suggested above? I know I have a batch of 1% resistors where the 100k looks exactly like a 10k, i.e. the red stripe looks like an orange stripe and vice versa......

Peter

Thanks Peter, yes I measured them twice and were hoping that that would have been the solution because thats the most obvious, but no.

Hard to understand, its strange that its the same in both channels.

You should do a signal tracer cable, and follow the schematic, tracing the circuit and figure out at which point does the sound drop. 
I would also guess its a wrong resistor value on the same place in both channels

Thanks! So it seems like it's the only possibility to have fault like this? I checked the boards again yesterday and eaven for some resistors that I wasn't sure measuring from the board I took one leg off and did the mesurment, also compared the bom to my mouser order confirmation(of course they make mistakes too).

Can it be something in the caps? Still there are just few different cap values and I have cheked them several times. Also tested with new opamps.

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on April 21, 2012, 12:57:48 AM
What could possibly cause the gainloss? Just cheked the gainloss is 14db's. Otherwise everything works great and the sound is good.
If it sounds good (read linear response) and no gain loss when bypassed, this will not be in the input stage or band stages.
Double check/measure the voltage divider R23 / R24 and double check the wiring and parts values of the summing resistors at your stepped gain switches.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sedit1 on April 21, 2012, 10:37:17 AM
What could possibly cause the gainloss? Just cheked the gainloss is 14db's. Otherwise everything works great and the sound is good.
If it sounds good (read linear response) and no gain loss when bypassed, this will not be in the input stage or band stages.
Double check/measure the voltage divider R23 / R24 and double check the wiring and parts values of the summing resistors at your stepped gain switches.

Measured r23/r24, all ok and also cheked wiring+summing resistors from the stepped switches all ok there. 36k5 going to sum and 100k/wiper going to opamps (using 11 steps +-5db configuration). This is starting to sound very odd, never had so much troubleshooting and not finding any problems  ???
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on April 21, 2012, 02:21:17 PM
cheked wiring+summing resistors from the stepped switches all ok there. 36k5 going to sum and 100k/wiper going to opamps (using 11 steps +-5db configuration).
Just to make sure, resistance between opamp-out in the freq.band stages (U1,U2,U3 pins 1 and 7) and summing node (U5 pin 2) is varying between 31K6 and 100K with R30 being 56K2 ?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: leafcutter on April 21, 2012, 02:38:45 PM
Quick Grounding question, I'm finishing up 4 nite eq's in a 2u case. I've grounded the AC earth to the case but I can't remember if the 0v/ground from the DC side of the green PSU should go to the case also?

Does my sketch look non-lethal?

Cheers John.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sedit1 on April 21, 2012, 03:17:04 PM
cheked wiring+summing resistors from the stepped switches all ok there. 36k5 going to sum and 100k/wiper going to opamps (using 11 steps +-5db configuration).
Just to make sure, resistance between opamp-out in the freq.band stages (U1,U2,U3 pins 1 and 7) and summing node (U5 pin 2) is varying between 31K6 and 100K with R30 being 56K2 ?

Thanks Harpo!

Sorry I meant 31k6 not "36k5" going to sum and thats the step 11 on lorlin and the first step is 100k like in your xls.

I measured the resistance( U5 pin 2) to  (U1,U2,U3 pins 1 and 7)  and The smallest value was 31k6 and the biggest was ~660k witch is the total value of the pot, Is this wrong?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on April 21, 2012, 05:42:15 PM
I measured the resistance( U5 pin 2) to  (U1,U2,U3 pins 1 and 7)  and The smallest value was 31k6 and the biggest was ~660k witch is the total value of the pot, Is this wrong?
Sorry, but wrong. You seem to have every resistor from the excelsheet wired in a series string of resistors (resistor between each switch step, instead of one side of the resistors connected to a switches throw lug and all resistors other side to a common ring). As already said and from the calcsheet, for +/-5dB smallest value would be 31K6 and biggest value 100K for the total value, but this is an easy fix.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: sedit1 on April 22, 2012, 04:21:41 AM
I measured the resistance( U5 pin 2) to  (U1,U2,U3 pins 1 and 7)  and The smallest value was 31k6 and the biggest was ~660k witch is the total value of the pot, Is this wrong?
Sorry, but wrong. You seem to have every resistor from the excelsheet wired in a series string of resistors (resistor between each switch step, instead of one side of the resistors connected to a switches throw lug and all resistors other side to a common ring). As already said and from the calcsheet, for +/-5dB smallest value would be 31K6 and biggest value 100K for the total value, but this is an easy fix.

Harpo, this is the best news in this week! So problem solved and now everything seems to be working like it should, I was thinking about this kind of mistake because it was my first stepped switch and  english is not my native language so it's easy to misunderstand some instructions.

Huge thanks to you! It's great that there is people like you in this board who are willing to give great advices and help to the people who need it. I'm going to make a donation to the forum right away!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Leonardo_007 on April 29, 2012, 11:54:22 AM
Hello,

is there one pcb left for me, please?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: glbaudio on June 18, 2012, 01:53:10 PM
is possible to have 2 PCBs?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on June 18, 2012, 02:37:44 PM
Sorry guys, all out at the moment. No plans for a re-order at the moment.

Peter
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: druu on June 25, 2012, 08:00:59 AM
I'm also very interested in PCB's! I need this EQ. Anyone know of any online PCB fabricators that don't have a minimum order? :P
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dagoose on July 27, 2012, 05:10:31 AM
Finally decided to make my nite EQ stepped because i love the sound but for mastering it is pretty much useless without switches, and that is a shame.
Just wondering what will be best because i see 2 versions in the sheet from Harpo.
One with a resistor in parallel with BBM switches and one without the parallel resistor and with a MBB switch.
Which one will be best? I will go for simple lorlins with max 5db boost and cut
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dagoose on July 29, 2012, 02:34:40 AM
No one?
Also wondering about the airband since it is just a positive value. I want 5db max boost with 0.5 db steps (= 11 steps) is it just a matter of using the sheet and set the cut value to 0 and max boost to 5? something like this?

Step   "Boost/Cut
value in dB"   "this is
voltage gain"   "required R in
(to substitute Rseries+RV)"   closest E96 value in ohms
1   0,000   1,0000   56200   56.200
2   0,500   1,0593   53056   53.600
3   1,000   1,1220   50088   49.900
4   1,500   1,1885   47286   47.500
5   2,000   1,2589   44641   44.200
6   2,500   1,3335   42144   42.200
7   3,000   1,4125   39787   40.200
8   3,500   1,4962   37561   37.400
9   4,000   1,5849   35460   35.700
10   4,500   1,6788   33476   33.200
11   5,000   1,7783   31604   31.600
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on July 30, 2012, 05:58:55 PM
...I will go for simple lorlins...
...that you can get as a BBM or as MBB switching type. Use the config that matches your type of switch.

Airband is always adding (no cut) and because of range overlap (the 2.5kHz shelfing band is part of the airband), you won't get a +0.5dB airband boost step without some cut of the corresponding shelfing band. All frequency stages aren't filters but bandwidth limited non-inverting gain stages with a 1st order -6dB slope that won't drop below unity gain, so the overall range of cut is limited to about -5dB .. -6dB when all bands get summed up.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: druu on July 30, 2012, 07:21:52 PM
Anyone have any PCB's for this?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: RATMNL on July 31, 2012, 08:48:19 AM
It's in the white market thread.... a lot of these have gone missing lately, so I don't know if Peter C. will ship them out still.. check the market, ask him!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dagoose on August 02, 2012, 01:20:59 PM
...I will go for simple lorlins...
...that you can get as a BBM or as MBB switching type. Use the config that matches your type of switch.

Airband is always adding (no cut) and because of range overlap (the 2.5kHz shelfing band is part of the airband), you won't get a +0.5dB airband boost step without some cut of the corresponding shelfing band. All frequency stages aren't filters but bandwidth limited non-inverting gain stages with a 1st order -6dB slope that won't drop below unity gain, so the overall range of cut is limited to about -5dB .. -6dB when all bands get summed up.
OK, great! i ordered BBM switches so i'll know what to do then :) I was already thinking of getting BBM in the first place, don't like the idea of open contacts. ;-)
But still wondering about the air band boost: what if all the bands are at 0 and you want the air boost to work from 0=off to + 5.5 db max in 0.5 db per step. What would be the way to calculate that? I'm a bit lost on the airband. All the other bands are clear.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dagoose on August 05, 2012, 04:28:22 AM
...I will go for simple lorlins...
...that you can get as a BBM or as MBB switching type. Use the config that matches your type of switch.

Airband is always adding (no cut) and because of range overlap (the 2.5kHz shelfing band is part of the airband), you won't get a +0.5dB airband boost step without some cut of the corresponding shelfing band. All frequency stages aren't filters but bandwidth limited non-inverting gain stages with a 1st order -6dB slope that won't drop below unity gain, so the overall range of cut is limited to about -5dB .. -6dB when all bands get summed up.
OK, great! i ordered BBM switches so i'll know what to do then :) I was already thinking of getting BBM in the first place, don't like the idea of open contacts. ;-)
But still wondering about the air band boost: what if all the bands are at 0 and you want the air boost to work from 0=off to + 5.5 db max in 0.5 db per step. What would be the way to calculate that? I'm a bit lost on the airband. All the other bands are clear.
anyone? what did you guys use for the airband?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Autophase on August 14, 2012, 06:46:07 AM
hi Guys,
I have done a couple of DIY builds in the past, I really would like to add a nice hardware EQ to my mastering chain, I really like the look of the Nite EQ, the fixed frequencies seem perfect for my needs.
Being that I will be using 2 of these in stereo for mastering, I figure I'll need to make stepped attenuators for all of the boost cut pots, is there anyone else who has done it this way who can offer any advice?

Thanks
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dagoose on August 14, 2012, 03:00:59 PM
ok.. what am i missing here? I just build one switch with + 5 (31k6) and -5 (100k) max boost/cut and i only get something like 1.5/2db of max boost and cut.  (testing it on the 650hz band)
With the potmeter i get something like 20db boost/cut so the circuit is Ok (it has been racked up for quite some time without problems).
If i use something like 5k6 for the boost i get (IIRC) 10db of boost.
Am i missing something here? 0 position is 0, it's just the max boost and cut that are way out of the range the sheet says.  :-[

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on August 15, 2012, 04:53:42 AM
Rseries (R39 for the 650Hz band) still in place instead of shorted out ?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dagoose on August 15, 2012, 05:16:52 AM
Rseries (R39 for the 650Hz band) still in place instead of shorted out ?
hmm.. so that is what i'm missing here.  :-[
They are indeed.. totaly missed that!
Thanks! 8)

EDIT: i shorted r39 and now i get a bit more boost (max 2.5 db) but still no 5db as it should be with 31k6.  ???
When i replace the 31k6 with 10k i get something like 5.5 db boost which is good. If i use the sheet with 10k max in the boost it says it's boosting 15db, which is totally different then the 5.5db i see.
With 330k for cut (= -15db according sheet) i get a cut of something like 3.5/4 db but with the 100k= -5db (according top sheet) i get only about 1db of cut.

anyone? I really don't get it..
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Autophase on August 15, 2012, 12:31:06 PM
Hi guys,
I have got a pair of boards & PSU all stuffed now.
I intend to use this EQ in stereo for mastering, so I will be opting for rotary switches for all cut/boost controls.
From reading through the forum I think I need 1 pole 12 way rotary switches, limited to 11 positions, position 6 being the centre.

Can you guys confirm if I've got that right?

Thanks
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: rob_gould on August 16, 2012, 05:00:17 AM

Yup that's right.  This is the plan for mine too, though it has been sitting in a  box half finished for the last three years.

You just need to decide the size of the steps for cut and boost.  There's a spreadsheet floating round somewhere on this thread which allows you to calculate resistor values which determine the size of the steps.  Courtesy of Harpo I believe.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Autophase on August 16, 2012, 05:11:10 AM
Yes I have seen the resistor tables, ill probably do the same as harpo and have 5x 1db steps each way.

Would anyone be able to clarify another thing for me please, i spent the afternoon reading most of this thread. To my understanding of stepped attenuators, each resistor goes a a lug on the switch then the other resistor leg goes to a common point, usually a ring or the same trace on some stripboard.
But I have seen in this thread some people wire the attenuator in series, so each step increase introduces another series resistor into the signal path, my concern with the series method is that it introduces more noise with each additional resistor in the signal path.

please can you clarifiy which is the correct / most accrate method for this eq? If I am missing something please fill me in, afterall the building is only half the reason I am here, the other half is to learn (and hopefully help someone else in the future)  ;D

sorry for bump, but I could do with some assistance on this please  :)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dagoose on August 24, 2012, 08:03:56 AM
OK, it's done!  8)
It works like a charm (already did but now with stepped switches, hard bypass, new knobs and a new frontpanel.

(http://www.dagoosemusic.nl/temp/nite1.jpg)
(http://www.dagoosemusic.nl/temp/nite2.jpg)
(http://www.dagoosemusic.nl/temp/nite3.jpg)
(http://www.dagoosemusic.nl/temp/nite4.jpg)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dagoose on August 25, 2012, 03:19:29 AM
For those looking for a front panel: http://www.groupdiy.com/index.php?topic=49638.0
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Autophase on September 05, 2012, 10:04:34 AM
Yes I have seen the resistor tables, ill probably do the same as harpo and have 5x 1db steps each way.

Would anyone be able to clarify another thing for me please, i spent the afternoon reading most of this thread. To my understanding of stepped attenuators, each resistor goes a a lug on the switch then the other resistor leg goes to a common point, usually a ring or the same trace on some stripboard.
But I have seen in this thread some people wire the attenuator in series, so each step increase introduces another series resistor into the signal path, my concern with the series method is that it introduces more noise with each additional resistor in the signal path.

please can you clarifiy which is the correct / most accrate method for this eq? If I am missing something please fill me in, afterall the building is only half the reason I am here, the other half is to learn (and hopefully help someone else in the future)  ;D

sorry for bump, but I could do with some assistance on this please  :)

Hi Guys, if anyone could give me a bit more guidence with the stepped switches that would be much appreciated.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Autophase on September 25, 2012, 05:41:38 AM
hey guys, has everyone abandoned this thread now?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Autophase on November 26, 2012, 08:59:00 AM
Hi Guys
sorry to ask the same question again, but this thread seems to have been inactive for a while, if anyone with experience of this EQ can help me that would be much appreciated

"I have seen the resistor tables, ill probably do the same as harpo and have 5x 1db steps each way.

Would anyone be able to clarify another thing for me please, i spent the afternoon reading most of this thread. To my understanding of stepped attenuators, each resistor goes a a lug on the switch then the other resistor leg goes to a common point, usually a ring or the same trace on some stripboard.
But I have seen in this thread some people wire the attenuator in series, so each step increase introduces another series resistor into the signal path, my concern with the series method is that it introduces more noise with each additional resistor in the signal path.

please can you clarifiy which is the correct / most accrate method for this eq? If I am missing something please fill me in, afterall the building is only half the reason I am here, the other half is to learn (and hopefully help someone else in the future) "

sorry for bump, but I could do with some assistance on this please 
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: druu on November 26, 2012, 09:22:27 AM
I'm probably not the best to answer but I would say series would be fine. Most of the guys here build there stepped controls in series and don't have a problem. Plus they're probably the cheapest method for stepped controls too. :)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Autophase on March 20, 2013, 09:43:36 AM
hi guys, this thread seems to have been left by the way side, can anyone who has built one of these or knows anything about it help me out at all?
I have a pari of stuffed boards and a PSU, I just need some help with the atenuators.
I want to use them in stereo for mastering and I was wondering if I could use these http://glass-ware.stores.yahoo.net/a5stat.html (http://glass-ware.stores.yahoo.net/a5stat.html)
it seems they would be set up with one knob controlling, 1db incriments and the second controlling minor incribments 1/6th db + or - in this case, i would obviously need a pair of knobs for each band, but I dont mind that so much.
Please let me know if you think this is possible.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on March 20, 2013, 11:36:01 AM
.., I just need some help with the atenuators.
None of the pots in this EQ is an attenuator. These rheostats set the amount of gain for the following summing stage.

Quote
I want to use them in stereo for mastering and I was wondering if I could use these http://glass-ware.stores.yahoo.net/a5stat.html (http://glass-ware.stores.yahoo.net/a5stat.html)
it seems they would be set up with one knob controlling, 1db incriments and the second controlling minor incribments 1/6th db + or - in this case, i would obviously need a pair of knobs for each band, but I dont mind that so much.
Please let me know if you think this is possible.
I wouldn't do it, but with a little redesign and some math to catch the then lawbending input resistors now in parallel to the shunt arm resistors of your attenuators, it seems possible.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Gustav on May 15, 2013, 04:55:34 AM
Just "for a laugh" I put the Nite EQ in a 500 series module last year;

(http://www.audiomaintenance.com/downloads/5003d_overview.jpg)

Faceplate looks like this;
http://www.audiomaintenance.com/downloads/5003d_front.jpg

and I even did a transformer output option PCB;
http://www.audiomaintenance.com/downloads/5003d_eq_transformer_option.jpg

It worked just fine, but slightly differently from the original in that when you boost a band it brings the "out of band" level down as well so it makes it difficult to overload (consequently the "Sub" band has the effect that the signal gets quieter when you increase the level..... because the "out of band" is basically every thing audible)...

There was one very small error on the PCB which I have now corrected.... but did not get any made.... I was thinking about getting a few boards made and then sending the gerbers to Gustav.....

... does anyone want these ?

Colin
www.audiomaintenance.com

FYI:I added these to the shop https://pcbgrinder.com/index.php?route=product/product&path=59_80&product_id=87 (https://pcbgrinder.com/index.php?route=product/product&path=59_80&product_id=87)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: geotone on May 15, 2013, 06:07:29 AM
Gustav, do you have any plans to offer this EQ in traditional format? Or is it easy enough to convert this for use in a standard 19" module?

Thanks, Geotone
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Gustav on May 15, 2013, 10:27:24 AM
Gustav, do you have any plans to offer this EQ in traditional format? Or is it easy enough to convert this for use in a standard 19" module?

Thanks, Geotone

I have to admit, I have never built a single thing in 500 series format og even looked at a 500 series frame, but I don't see why you shouldn't be able to do that unless theres some esoteric, theoretical barrier I didn't think of. http://www.lunchboxhero.com/resources/docs/tek/api_pinout.jpg

And to avoid soldering directly to the gold fingers..
http://www.sonicworld.eu/Vintage-Gear/Connectors/Connectors-for-Vintage-Modules/305-Female-connector-for-API-500-Serie-Modules-used

Maybe I should stock a few of those female connectors.

Gustav
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: shot on May 15, 2013, 07:43:00 PM
I was contemplating on the concept of having rotary switch change values only in one direction and an additional toggle switch to choose if it will cut or boost. Came up maybe with a solution but I still need verification.

I went from the assumption that rev log pots use 90% of their values on one side of the rotation. So if we take 500K pot and divide it into plus and minus sections (boost and cut) it would be left half (CCW to center) with total value of 450K and right half (center to CW) with 50K. In this arrangement used in EQ-3D filter sections maximum cut would be equal to maximum resistance (450K+50K), center would be 50K resistance and maximum boost would be zero ohm.

From that point I went to draw an ideal schematic that would use 2 throw switch (more expensive solution).
This would be easy since different resistor series could be used for boost and cut.
If it was cutting, switch total resistance would be 450K + fixed 50K.
In the boost position it would be the same series resistance on the switch 450K but paralleled with 56K2 resistor to have it range from zero to 50K.

My next task was to come up with a way of using only one rotary with 1 pole in either boost or cut. The complicated thing here is that boost and cut would end up in different orientation - minimum for boost would be maximum for cut and vice versa.

So I came up with this schematic attached here to overcome that problem - Could someone check if this will work.

Rotary switch resistors would probably have to be linear scaled - probably 450K divided to 11 if using Lorlin 12P1T = 40K each. Or in reality 39K with modified values for fixed resistors to keep the total resistances stable. Or even some other value if targeting different boost/cut amount.

I suck in simulation software so I was unable to sim this schematic to see what would it show!

Please comment!
 :)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dagoose on May 16, 2013, 05:20:58 AM
why not use a 2 deck switch, one deck for boosting, one deck for cutting and use a switch to switch between both sides of the switch? I think that will be way more simple.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: whomper on May 16, 2013, 10:21:26 AM
Have just completed my unit and am wondering whether others also see the frequency response plot I am getting.

The attached file is a Fireface 800<->NightEQ left channel loopback (Out to In to Out to In) and my attempt at getting flat response when the EQ is engaged.

Am getting about -1db drop at 75Hz, -0.4 at 310Hz and -0.2 at 1.8KHz no matter how I try to zero it.
Both left and right channels exhibit a very similar curve.

Are others getting a similar response?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: shot on May 16, 2013, 11:16:08 AM
why not use a 2 deck switch, one deck for boosting, one deck for cutting and use a switch to switch between both sides of the switch? I think that will be way more simple.

Yes, that was my first idea!
But then I was puzzled if it could be done with only one deck so I came up with this.
I haven't tested it but in theory I think it should work.
:)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on May 16, 2013, 04:54:16 PM
I was contemplating on the concept of having rotary switch change values only in one direction and an additional toggle switch to choose if it will cut or boost. Came up maybe with a solution but I still need verification.

I went from the assumption that rev log pots use 90% of their values on one side of the rotation. So if we take 500K pot and divide it into plus and minus sections (boost and cut) it would be left half (CCW to center) with total value of 450K and right half (center to CW) with 50K. In this arrangement used in EQ-3D filter sections maximum cut would be equal to maximum resistance (450K+50K), center would be 50K resistance and maximum boost would be zero ohm.
Cut (CCW direction) would be between 500K and 50K. Boost (CW direction) would be between 50K and zero. Add the 5K62 fixed series resistance on top. Voltage gain is set by R30/(pot value + fixed seriesR), IE between 56200/(0+5620)=10 and 56200/(500000+5620)=0.111 or in dB between LOG(10)*20=+20dB and LOG(0.111)*20=-19.1dB per bandwidth limited gain stage feed and an R24/(R24+R25) attenuator in front. 

Quote
So I came up with this schematic attached here to overcome that problem - Could someone check if this will work.
Will work, but I'm sure you won't like it, switching from min.cut to max.boost in CCW position and vice versa, so two additional switch poles would at least connect the rotary switch upside down and your law bending 56K2 when switched to boost will give you 9 steps for a total of 2dB boost and 14.25dB in the last (from your pic the 1st.) step.

Quote
Rotary switch resistors would probably have to be linear scaled
probably not ...

Quote
I suck in simulation software so I was unable to sim this schematic to see what would it show!
Just fill in your switched resistor values in previous formula to get an idea what the result might be.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: shot on May 17, 2013, 04:22:22 AM
You're right Harpo!
Now I see my mistakes.
Thanks for your help!

I have to travel for few days on gigs and when I come back I'll look into it more.

I don't have problem using two pole switch but it's kinda intriguing for me to explore and contemplate more on this one pole design. You gave me a good food for thought now!  :)

And btw, I'm really impressed on the pot tweaking documents you did. Wow! Respect!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on May 19, 2013, 07:27:43 PM
Am getting about -1db drop at 75Hz, -0.4 at 310Hz and -0.2 at 1.8KHz no matter how I try to zero it.
Reason for your response curve is, these bands are not filters but bandwidth limited gain stages. Center frequency of each band has to be exactly 2 oct. = factor 4 apart, so the -6dB/oct. slope adds up to unity gain with its neighbouring gain stage. If FI for the typo '650Hz' band (should be 640Hz) you have fitted 120R and 1K2 resistors instead of from schematic 127R and 1K27 resistors (ideal value would be 124.3R and 1K243 with perfect 2uF and 200nF caps, if neighbouring lower stage would be set for 160Hz for real instead of 156Hz), this frequency band will rise from 627Hz to 663Hz, giving your shown dip at 321Hz for this example value.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: whomper on May 23, 2013, 12:06:16 PM
Reason for your response curve is, these bands are not filters but bandwidth limited gain stages. Center frequency of each band has to be exactly 2 oct. = factor 4 apart, so the -6dB/oct. slope adds up to unity gain with its neighbouring gain stage. If FI for the typo '650Hz' band (should be 640Hz) you have fitted 120R and 1K2 resistors instead of from schematic 127R and 1K27 resistors (ideal value would be 124.3R and 1K243 with perfect 2uF and 200nF caps, if neighbouring lower stage would be set for 160Hz for real instead of 156Hz), this frequency band will rise from 627Hz to 663Hz, giving your shown dip at 321Hz for this example value.

Harpo, thanks for the elaborated explanation. Think I have chosen the 120R/1K2 combo.

Looking at the response curve I am getting, might it be that the Q factor is a little too narrow? Even if I will move the 650Hz around a little, I am not sure it will level the 350Hz dip I am getting.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on May 23, 2013, 01:26:46 PM
Looking at the response curve I am getting, might it be that the Q factor is a little too narrow? Even if I will move the 650Hz around a little, I am not sure it will level the 350Hz dip I am getting.
With correct distance between these bands they will add up to a flat response and you won't change the fixed -6dB/oct slope.
You might adjust resistor values (seems easier than adjusting the 1uF or 100nF cap values) in a way, this 1/(2PI()*R*C) for the HPF and LPF setting in the lower 4 bands is exactly factor 4=2 oct. apart from its neighbouring band, IE 10Hz, 40Hz, 160Hz, 640Hz. Reason there are always 2 caps in parallel in these bandwidth limited gain stages is, to get statistically closer to the ideal caps value because parts come with tolerances that might cancel out by this paralleling (for example: ideal caps value 1uF||1uF=2uF; real world caps are maybe 0.974uF||1.030uF=2.004uF).
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: positrons on June 02, 2013, 04:20:01 AM
nobody has the PCB for PSU?? :-\
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bm_dong on June 10, 2013, 11:50:20 PM
Does anybody have the self etch files for this?

It would be greatly appreciated!

EDIT: Nevermind! found em!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Rockitdog on June 19, 2013, 04:16:58 AM
Just incase anyone else is looking for them.

http://www.twin-x.com/groupdiy/thumbnails.php?album=485

Thanks to Peterc for these.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: positrons on July 05, 2013, 03:58:19 PM
Hi friends,I have few questions about this Project. :)

1.about connecting rotary switch to PCB,what are the Q and b pins??and next to Q we have 2-6, what does it mean??and pin 1 shouldn't be connected to anywhere?
2.Under R26 we have a resistor,what does it mean by 0R link??put a jumper instead of this resistor??
3.why some people put jumper instead of CIN1 and CIN2 Caps??
4.why we have 4 pins for LED??both of them are connected to the same source!!!

Thank you everyone. :) ;)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: pachi2007 on July 07, 2013, 11:25:54 AM
May seem "Q" but it´s "A"
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: pachi2007 on July 07, 2013, 11:49:11 AM
I think this is correct but please verify
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on July 07, 2013, 12:11:02 PM
I think this is correct but please verify
the shorting links between 2a,3a,4a,5a and 6a are missing in the pic, else only the 'off' and 2.5kHz settings would work. Just have a look at the schematic (schematic and previous posts should explain positrons remaining questions as well).
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on July 07, 2013, 03:23:08 PM
As harpo says, do the shorts, but I think that is indicated in the pic?

0R link is the same as a jumper.

Input caps can be replaced for DC coupling.

The 2 pairs of pins are in parallel, so only 2 connections.

Peter
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: pachi2007 on July 07, 2013, 03:41:57 PM
Thx Harpo and Peter.
I took a look and I think I got it now. I hope :-)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: pachi2007 on July 07, 2013, 03:43:53 PM
From schem
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: positrons on July 07, 2013, 04:20:16 PM
Thank you to all of you.I understood all of them. ;D

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: positrons on July 14, 2013, 06:00:34 PM
Hi again, :D
 I bought two types of rotary switch 2*6 and there is a difference between them.one of them is like this
1.
(http://www.groupdiy.com/index.php?action=dlattach;topic=19789.0;attach=21484;image)

and the other is like this:
2.
(https://www.tube-town.net/ttstore/images/product_images/original_images/3703_0.jpg)

both of them are 2*6 but when I turn number 1,it seems that it has 12 positions because it says TIK 11 times,but number 2 has 6 positions and it says TIK 5 times!!!

which one is correct??we want 6 positions according to the original version of EQ,isn't it??why number 2 says TIK 11 times whereas it has 2 pins in the middle and 12 pins around them??

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on July 14, 2013, 07:07:08 PM
for pic1 turn the switch full CCW, remove the fixing nut, remove the washer and displace the end-stop washer to pos.6. done.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: positrons on July 15, 2013, 09:00:17 AM
for pic1 turn the switch full CCW, remove the fixing nut, remove the washer and displace the end-stop washer to pos.6. done.
Thank you Harpo ;D.I didn't pay attention to that washer.Shame on me :P
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on July 16, 2013, 08:20:08 PM
nobody has the PCB for PSU?? :-\

The PSU PCB is the same used in the green pre.

You can also use the PSU PCB from Gustav used in the SSL 9K project
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: positrons on July 19, 2013, 08:12:22 AM
nobody has the PCB for PSU?? :-\

The PSU PCB is the same used in the green pre.

You can also use the PSU PCB from Gustav used in the SSL 9K project

Thank you for your help.
you mean This PSU??

http://www.lorcan.me/wordpress/wp-content/uploads/2011/09/layout.png

I don't understand output of this supply.why it has for pins??and what are the names??+ - and Ground??

another question,GREEN Mic pre is the clone version of focusrite GREEN???is it a good pre??you think it is worth to make it?? :)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on July 19, 2013, 10:02:24 AM
http://www.lorcan.me/wordpress/wp-content/uploads/2011/09/layout.png
I don't understand output of this supply.why it has for pins?? and what are the names??+ - and Ground??
The four pins from left to right are 0V reference voltage and +15V, -15V, +48V in respect to this 0V reference voltage.
For the 3D-EQ you don't need the +48V phantom voltage rail, so you'd leave out all parts above the AC-input connector and left side of the 1000uF/35V caps, just keep the 4 rectifying diodes between AC-input connector and bottom 1000uF/35V cap.

Quote
another question,GREEN Mic pre is the clone version of focusrite GREEN???is it a good pre??you think it is worth to make it?? :)
Just look up the green-pre in the meta or read the green-pre help thread. ;)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: positrons on July 19, 2013, 04:36:37 PM
http://www.lorcan.me/wordpress/wp-content/uploads/2011/09/layout.png
I don't understand output of this supply.why it has for pins?? and what are the names??+ - and Ground??
The four pins from left to right are 0V reference voltage and +15V, -15V, +48V in respect to this 0V reference voltage.
For the 3D-EQ you don't need the +48V phantom voltage rail, so you'd leave out all parts above the AC-input connector and left side of the 1000uF/35V caps, just keep the 4 rectifying diodes between AC-input connector and bottom 1000uF/35V cap.

Quote
another question,GREEN Mic pre is the clone version of focusrite GREEN???is it a good pre??you think it is worth to make it?? :)
Just look up the green-pre in the meta or read the green-pre help thread. ;)

Thank you so much Harpo for your excellent explanation. :)
I will read the topics, I only wanted to know that what is this micpre and see one pic from the original factory made version.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on July 20, 2013, 08:43:07 AM
I will read the topics, I only wanted to know that what is this micpre and see one pic from the original factory made version.
Pic from an ancient A*** console? Nuthin to do with Ficusrote. No cloning of units that are still in production or still on sale here.
It is a mic preamp. IMHO the room, mic placement and performance in front of the mic are 99% of perceived differences between preamps. YMMV.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: positrons on July 20, 2013, 11:38:30 AM
I will read the topics, I only wanted to know that what is this micpre and see one pic from the original factory made version.
Pic from an ancient A*** console? Nuthin to do with Ficusrote. No cloning of units that are still in production or still on sale here.
It is a mic preamp. IMHO the room, mic placement and performance in front of the mic are 99% of perceived differences between preamps. YMMV.

yes pic from an ancient A*** console :) yes you are right the room, mic placement and performance in front of the mic are 99% of perceived differences between preamps.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: positrons on July 22, 2013, 06:55:55 PM
I finished one channel of EQ and tested it but it dos not work :(
I am trying to find the problem and I have several questions and need your help.thank you for your helps friends. :)

1.I don't make the PSU yet and I used Calreq EQ PSU(jakob Calreq) for testing.the voltage is 18.has it any problem??

2.It doesn't have any sound even when it is bypass!!it should have sound in bypass mode even without PSU isn't it??like calreq EQ.if i am right,where is my first mistake??

3.I couldn't find the revers log 500K pots and I changed the taper of the 500k linear pot with soldering a 100K resistor between pins like this
(http://www.jt30.com/jt30page/potfix/pot2.gif)

which one can make problem in this project??if non of them,please help me to start troubleshooting. :)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on July 23, 2013, 05:45:00 AM
1.I don't make the PSU yet and I used Calreq EQ PSU(jakob Calreq) for testing.
Why do you want to change the PSU to a different PSU then?
Quote
the voltage is 18.has it any problem??
Depends on the type of fixed voltage regulators (78xx/79xx) you used and the secondary voltages of the center tapped or dual mains transformer. The NE5532 and NE5534 opamps will have no problem with your probably +/-18VDC supply (=36VDC between PSU out + and - with 0V reference voltage in between.)
Try to be more exact with your numbers, and signs matter. Your 'the voltage is 18' could as well be a +/-9VDC supply when you used 7809/7909 vregs.

Quote
2.It doesn't have any sound even when it is bypass!!it should have sound in bypass mode even without PSU isn't it??like calreq EQ.if i am right,where is my first mistake??
Your mistake simply is in assuming, any bypass circuit will behave the same and have the same circuit behind. If you would have taken a look at the schematic, you'd recognized that this unit doesn't come with a hard bypass.

Quote
3.I couldn't find the revers log 500K pots and I changed the taper of the 500k linear pot with soldering a 100K resistor between pins like this
Your pic shows a voltage dividing attenuator (3-legged device) to mimic a pos.log taper pot by paralleling a law bending/slugging resistor between wiper and the CCW end of the linear taper pot. This might work in some circuits that more or less are not depending on a defined total load value. (Sending device sees 500K with pot wiper full CCW and sees 83K3 with pot wiper full CW).
None of the pots in this circuit is wired as an attenuator. The pots in this circuit are wired as rheostats (2-legged device) with ~10% of its total value at half rotation. Unfortunately you can't mimic a rev.log taper rheostat from a lin.taper pot by paralleling a resistor between wiper and either end.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on July 23, 2013, 07:02:04 AM
Some steps to fault find the problem.

1. Take out all the IC's. Power up and make sure you measure +18v on pin 8 of the IC sockets, and -18v on pin 4. Remember, U5 is a single opamp (NE5534) so +18v will be on Pin 7. Power down.

2. Put the ICs back in. to check the input/de-balancing stage is working, apply a balanced signal to the input. Use a scope to measure the output (pin 7 U4). If this is OK, then the input section is working.

3. To check the output/balancing stage is working.  Apply an unbalanced signal to Pin 2 of U5. Check for equal but out of phase signals on the output pins.


Peter
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: positrons on July 23, 2013, 07:26:45 AM
1.I don't make the PSU yet and I used Calreq EQ PSU(jakob Calreq) for testing.
Why do you want to change the PSU to a different PSU then?
Quote
the voltage is 18.has it any problem??
Depends on the type of fixed voltage regulators (78xx/79xx) you used and the secondary voltages of the center tapped or dual mains transformer. The NE5532 and NE5534 opamps will have no problem with your probably +/-18VDC supply (=36VDC between PSU out + and - with 0V reference voltage in between.)
Try to be more exact with your numbers, and signs matter. Your 'the voltage is 18' could as well be a +/-9VDC supply when you used 7809/7909 vregs.

Quote
2.It doesn't have any sound even when it is bypass!!it should have sound in bypass mode even without PSU isn't it??like calreq EQ.if i am right,where is my first mistake??
Your mistake simply is in assuming, any bypass circuit will behave the same and have the same circuit behind. If you would have taken a look at the schematic, you'd recognized that this unit doesn't come with a hard bypass.

Quote
3.I couldn't find the revers log 500K pots and I changed the taper of the 500k linear pot with soldering a 100K resistor between pins like this
Your pic shows a voltage dividing attenuator (3-legged device) to mimic a pos.log taper pot by paralleling a law bending/slugging resistor between wiper and the CCW end of the linear taper pot. This might work in some circuits that more or less are not depending on a defined total load value. (Sending device sees 500K with pot wiper full CCW and sees 83K3 with pot wiper full CW).
None of the pots in this circuit is wired as an attenuator. The pots in this circuit are wired as rheostats (2-legged device) with ~10% of its total value at half rotation. Unfortunately you can't mimic a rev.log taper rheostat from a lin.taper pot by paralleling a resistor between wiper and either end.

thank you for your response.
why do you say (Your mistake simply is in assuming)????????? ???

I don't want to change the PSU I Said for testing I used Calreq PSU because I haven't made PSU yet and I had one of those calreq PSU and the voltage is +18 and -18 and regulators are 7918 and 7818.

2.It seems that I should try to find rev log 500K pot and this method doesn't work here.my reference was http://music-electronics-forum.com/attachments/737d1181440399-pot_taper_amz.pdf  (http://music-electronics-forum.com/attachments/737d1181440399-pot_taper_amz.pdf) but I don't know the difference between attenuator and rheostats resistors in circuits.

3.what do you mean by hard bypass?when in bypass mode I have no sound, which part of circuit can have problem??when I check connections between TRS jack pins with multimeter,they are not connected to each other.is it possible to explain it clearly for me??I am a beginner in electronics and not a pro like you :)

4.why do some people put jumper instead of 22u caps??peter said (
Input caps can be replaced for DC coupling) but i don't understand.
thank you for your patience.  :)

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: positrons on July 23, 2013, 07:31:13 AM
Some steps to fault find the problem.

1. Take out all the IC's. Power up and make sure you measure +18v on pin 8 of the IC sockets, and -18v on pin 4. Remember, U5 is a single opamp (NE5534) so +18v will be on Pin 7. Power down.

2. Put the ICs back in. to check the input/de-balancing stage is working, apply a balanced signal to the input. Use a scope to measure the output (pin 7 U4). If this is OK, then the input section is working.

3. To check the output/balancing stage is working.  Apply an unbalanced signal to Pin 2 of U5. Check for equal but out of phase signals on the output pins.


Peter

thank you peter.first of all,my problem is bypass mode now.I said to harpo in previous post.if you know that pleas help me.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on July 23, 2013, 07:44:37 AM
The bypass is after the input stage.

Input XLR  -->  un-balancing stage  -->  bypass switch/EQ  --> balancing stage  --> output XLR

You can leave in the 22uF caps with no difference.

If you are a beginner, then build the circuit as is before changing it.

Peter
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on July 23, 2013, 08:48:29 AM
why do you say (Your mistake simply is in assuming)????????? ???
Refers to your assumption 'it should have sound in bypass mode even without PSU isn't it??like calreq EQ.' The calreq EQ (different circuit) simply connects XLR-in with XLR-out by use of a DPDT switch. This will work without a PSU connected. If this calrec EQ bypass function would be made by a DPDT relais instead of a simple switch, the relais default setting would have to be wired for this bypass setting, else this wouldn't work either without PSU operating to activate the change over. This 3D-EQ circuit operates the bypass function different again. The balanced line receiver debalances the incoming differential voltage and instead of summing all bandwidth limited gain stages, the bypass switch now connects this audio voltage thru the 56K2 resistor R48 to the inverting summing stage. This requires the opamps to be working, what these wouldn't without working supply.

Quote
I don't want to change the PSU I Said for testing I used Calreq PSU because I haven't made PSU yet and I had one of those calreq PSU and the voltage is +18 and -18 and regulators are 7918 and 7818.
Whats wrong in using this already working psu. No need to build another for the same purpose.

Quote
2.It seems that I should try to find rev log 500K pot and this method doesn't work here.my reference was http://music-electronics-forum.com/attachments/737d1181440399-pot_taper_amz.pdf  (http://music-electronics-forum.com/attachments/737d1181440399-pot_taper_amz.pdf) but I don't know the difference between attenuator and rheostats resistors in circuits.
A rheostat is a variable resistor between two pins, not referencing a 3rd potential.
The shown attenuator from your pic is a voltage divider with the incoming signal at one end, a 0V reference voltage at the opposing end and the attenuated signal at the pots wiper in respect to this reference voltage.

Quote
3.what do you mean by hard bypass?
Hard bypass is connecting device input to device output by a direct connection, leaving the function of this device itself disconnected. Soft bypass (FI the unity gain setting for the 3D-EQ or forcing a VCA in its current-in=current-out condition for a GSSL compressor circuit) requires the device powered on.

Quote
4.why do some people put jumper instead of 22u caps??peter said (
Input caps can be replaced for DC coupling) but i don't understand.
If you are sure, any sending device that might send signal to your 3D-EQ is free of DC offset voltages, you could leave out these DC-blocking coupling caps with -3dB cutoff set for 0.72Hz. Wouldn't change much because balanced line receiver operates at voltage gain of 0.5 and has a DC blocking cap connected to its output.

oops, Peter already answered.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on July 23, 2013, 02:13:14 PM
No problem, Harpo, thanks for the input
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: positrons on July 24, 2013, 04:44:04 PM
Some steps to fault find the problem.

1. Take out all the IC's. Power up and make sure you measure +18v on pin 8 of the IC sockets, and -18v on pin 4. Remember, U5 is a single opamp (NE5534) so +18v will be on Pin 7. Power down.

2. Put the ICs back in. to check the input/de-balancing stage is working, apply a balanced signal to the input. Use a scope to measure the output (pin 7 U4). If this is OK, then the input section is working.

3. To check the output/balancing stage is working.  Apply an unbalanced signal to Pin 2 of U5. Check for equal but out of phase signals on the output pins.


Peter

Peter I checked IC voltage and they are correct.but I don't have scope,how can I check (the input/de-balancing stage)???
before soldering,I checked all component except inductors,how can I check them?also I checked back of the PCB and there is no shorts and soldering problem,I don't change the pots yet and they are 500K liner with 100k resistor soldering between 2 pins,are they problematic parts or not???I have no sound in active and bypass mode!!!! :(
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on July 25, 2013, 05:03:49 AM
I don't have scope,how can I check (the input/de-balancing stage)???
Feed the input XLR with a balanced or unbalanced signal at a frequency your multimeter can handle (maybe 300Hz sine). Amplitude doesn't matter much, as long as its peak value is below the supply rail voltages and more than zero V (maybe 100mV ... 1V). Take your multimeter, set for measuring AC voltage and measure between XLR-pins2/3. Confirm same value ariving at J1-pins2/3. Write down this measured voltage. Now measure AC voltage between U4-pin1 and 0V reference voltage. This measured voltage will be half the value of previously noted voltage (this stage has voltage gain of 0.5=-6dB).

Quote
I don't change the pots yet and they are 500K liner with 100k resistor soldering between 2 pins,are they problematic parts or not???
If the pots are connected as shown in your previously shown pic (without the black wires), you don't have a 100k resistor between 2 pins, as the leftmost CCW pin and wiper connection are joined on schematic and pcb, so your 100k resistor is shorted out as well. The pot, wired as rheostat, varies resistance between wiper connection and rightmost CW pin (between the red wires from your pic), setting the amount of gain of the inverting summer for the frequency band it controls (rheostats highest resistance value gives lowest gain and vice versa). With your linear taper pots you'd have to dial them in for ~90% of rotation for the otherwise +/-0dB center position of pots with rev.log taper.

From 3. of Peters reply, DON'T apply a signal to U5-pin2 directly (will most likely kill the opamp, missing a current limiting/gain setting input resistor). Apply this at the junction R5/R25/R48/C1 and switch the unit to bypass, so R48 is in circuit as this required resistor. Otherwise as Peter posted.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Sammas on July 27, 2013, 07:10:01 AM
Just "for a laugh" I put the Nite EQ in a 500 series module last year;

(http://www.audiomaintenance.com/downloads/5003d_overview.jpg)

Faceplate looks like this;
http://www.audiomaintenance.com/downloads/5003d_front.jpg

and I even did a transformer output option PCB;
http://www.audiomaintenance.com/downloads/5003d_eq_transformer_option.jpg

It worked just fine, but slightly differently from the original in that when you boost a band it brings the "out of band" level down as well so it makes it difficult to overload (consequently the "Sub" band has the effect that the signal gets quieter when you increase the level..... because the "out of band" is basically every thing audible)...

There was one very small error on the PCB which I have now corrected.... but did not get any made.... I was thinking about getting a few boards made and then sending the gerbers to Gustav.....

... does anyone want these ?

Colin
www.audiomaintenance.com


I am gearing up to make a pair of these bad boys... but have hit a bit of a hurdle when ordering parts.
Most of it is pretty straight forward - the bits I have zero experience with is the ferrite beads.

CL1       EMI Filter - Murata  Ferrite Bead          DSC
CL2       EMI Filter - Murata  Ferrite Bead          DSC
--------------------------------------------------------
F1        Ferrite Bead  Ferrite Bead          DSC
F2        Ferrite Bead  Ferrite Bead          DSC

Can anyone give me a hint which type I am ordering? The Murata ferrite beads in particular look pretty unique as they have 3 legs!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Indecline on July 27, 2013, 11:13:00 AM
They are plain jane ferrite inductors that look like a thick resistor. I grabbed a couple Vishay's for mine, although you could probably use a wire link and get by just fine.
Title: Finished, but not working properly...
Post by: Anthropic on July 31, 2013, 05:53:18 PM
Hey everyone,

I just completed four channels of the Night EQ.  However, when a signal is sent through them, I'm getting an enormous amount of hum on all four channels (2 channels in each 1-space rack).  The (1kHz at 0dB) signal I'm sending it gets through, but it's very quiet and masked by the hum.

Actually, the hum sounds very similar to the sound you'd get if you had an unterminated input to a high-gain amp.  I'm a pretty experienced builder, so I don't think I made any resistor/capacitor value errors, but it's possible.  I'm leaning to the cause being some sort of grounding problem.  Does anyone have any special grounding "tricks" for this project?  I've simply attached a lead from the GROUND connection on the AC input side of the Green PSU to the chassis ground lug (where the AC ground from the wall jack is also grounded).  The EQ boards get their grounds from the GROUND connection on the other side of the Green PSU board (where the -+18V is supplied).  The XLR inputs/outputs have their PIN 1 connected to the GROUND connection area on the EQ boards.  This (from pictures I've seen) seems to be the way everyone else is wiring theirs. 

Any ideas?  I've tried swapping OP AMPs, etc., but since the problem is common to all 4 channels I assume something else has gone awry.  Thanks!

Dan
Title: Re: Finished, but not working properly...
Post by: Indecline on August 01, 2013, 01:36:28 PM
Hey everyone,

I just completed four channels of the Night EQ.  However, when a signal is sent through them, I'm getting an enormous amount of hum on all four channels (2 channels in each 1-space rack).  The (1kHz at 0dB) signal I'm sending it gets through, but it's very quiet and masked by the hum.

Actually, the hum sounds very similar to the sound you'd get if you had an unterminated input to a high-gain amp.  I'm a pretty experienced builder, so I don't think I made any resistor/capacitor value errors, but it's possible.  I'm leaning to the cause being some sort of grounding problem.  Does anyone have any special grounding "tricks" for this project?  I've simply attached a lead from the GROUND connection on the AC input side of the Green PSU to the chassis ground lug (where the AC ground from the wall jack is also grounded).  The EQ boards get their grounds from the GROUND connection on the other side of the Green PSU board (where the -+18V is supplied).  The XLR inputs/outputs have their PIN 1 connected to the GROUND connection area on the EQ boards.  This (from pictures I've seen) seems to be the way everyone else is wiring theirs. 

Any ideas?  I've tried swapping OP AMPs, etc., but since the problem is common to all 4 channels I assume something else has gone awry.  Thanks!

Dan

It's possible there's a ground loop in there. Try removing audio ground (eq board) off of the PSU ground to a star grounding scheme. IIRC, XLR pin 1 ties to chassis ground by the IEC inlet. Do a search for 'star ground' on the forum, you'll find plenty of threads on the topic.

Let us know how it works out!
Title: Grounding Issue
Post by: Anthropic on August 01, 2013, 08:52:42 PM
Thanks INDECLINE

I did a few tests today.  My problem definitely seems to be grounding-related.  Running Pink noise through the EQ and turning the knobs, I'm able to cut/boost all of the frequencies with no problem (as intended).  Also, the frequency selector switch is fully functional.  Still, the test tones are nearly completely obscured by the "ground loop" hum I described in my previous post. 

In attempt to find a quiet ground scheme, I did the following:

- disconnected the grounds from the EQ board to the IN/OUT XLR jacks.  This added a loud buzz to the output signal.
- unscrewed the XLR jacks from the chassis (to remove the possibility of a loop through the chassis).  This did little, if anything to the hum.
- disconnected the ground wire that ran from the Green PSU to the EQ board's -+18V input area and connected that EQ board Ground input directly to star ground.  This produced a significant reduction in hum, but a large portion remains.
- I've also run PIN 1 on the XLR jacks directly to star ground (rather than to the Ground connection on the EQ Board XLR IN/OUT).  This did nothing to reduce the hum.

Some hints:

- the hum seems output-based (rather than hum induced at the input).
- the volume of the test tones (in relation to the hum) is louder when the EQ is in BYPASS. 


Does anyone have a grounding plan that has produced reliably quiet results with this EQ?  Since the grounding between individual portions of the EQ is set by the construction of the board (and presumably works well), the ground wiring of the boards/XLR jacks must be critically important. 

Thanks for the help so far!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on August 02, 2013, 02:47:38 AM
Dan

Do you have a scope to check the ripple on your PSU rails?

Getting back to the grounding issue, can you take the PCB out of the chassis, to eliminate that component.

Start simply, connect one channel to the PSU.

Peter
Title: Re: Finished, but not working properly...
Post by: Harpo on August 02, 2013, 06:11:04 AM
The (1kHz at 0dB) signal I'm sending it gets through, but it's very quiet and masked by the hum.
Your signal connects between XLR-pins2/3 (the balanced line receiver exclusively operates the differential between these pins 2/3). XLR-pin1 connects to the cable shield and case by a shortest possible connection. When using shielded cable for audio inside your unit, connect the shield at one side only, else you most likely build a ground loop. You might have an unbalanced signal connected between XLR-pins1/2 and pin3 left floating.
The 1kHz at 0dBanana (is it dBu, dBV, dBFS, ...?) doesn't say what level you are sending. You could check the level at the output of the line receiver for half the level you sent in by measuring the AC voltage, so you know the unbalancing is working properly.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: whomper on August 03, 2013, 04:23:18 AM
Hi,

Trying to apply the EQ to some mastering applications that I have, the Cut/Boost potential is way too big for my use. Is there a way to cut by half the Cut/Boost range with a simple mod?

Also, can others post sample freq curve of their EQ builds? Trying to see how mine (posted earlier) compare to see whether I should play some more with resistor values of the 650 (or 640Hz) band or what others get is inherently similar to mine.

Thanks.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: positrons on August 03, 2013, 04:25:54 AM
I don't have scope,how can I check (the input/de-balancing stage)???
Feed the input XLR with a balanced or unbalanced signal at a frequency your multimeter can handle (maybe 300Hz sine). Amplitude doesn't matter much, as long as its peak value is below the supply rail voltages and more than zero V (maybe 100mV ... 1V). Take your multimeter, set for measuring AC voltage and measure between XLR-pins2/3. Confirm same value ariving at J1-pins2/3. Write down this measured voltage. Now measure AC voltage between U4-pin1 and 0V reference voltage. This measured voltage will be half the value of previously noted voltage (this stage has voltage gain of 0.5=-6dB).

Quote
I don't change the pots yet and they are 500K liner with 100k resistor soldering between 2 pins,are they problematic parts or not???
If the pots are connected as shown in your previously shown pic (without the black wires), you don't have a 100k resistor between 2 pins, as the leftmost CCW pin and wiper connection are joined on schematic and pcb, so your 100k resistor is shorted out as well. The pot, wired as rheostat, varies resistance between wiper connection and rightmost CW pin (between the red wires from your pic), setting the amount of gain of the inverting summer for the frequency band it controls (rheostats highest resistance value gives lowest gain and vice versa). With your linear taper pots you'd have to dial them in for ~90% of rotation for the otherwise +/-0dB center position of pots with rev.log taper.

From 3. of Peters reply, DON'T apply a signal to U5-pin2 directly (will most likely kill the opamp, missing a current limiting/gain setting input resistor). Apply this at the junction R5/R25/R48/C1 and switch the unit to bypass, so R48 is in circuit as this required resistor. Otherwise as Peter posted.

Thank you harpo for your helps. my problem is solved. :)the problem was those two 22u caps!!!!!I remove them and put jumper instead of them and now I have sound.I didn't understand the reason of that. ???
I don't change the pots yet and they are linear and they don't work properly.I will change them.
one quastion :Dwhen I connect output of EQ to input of my speakers with TS cables,I hear a little bit of distortion!!but when I connect the output to a headphone,there is no distortion.what is the reason for that?should I use TRS cable only??
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: positrons on August 03, 2013, 04:33:39 AM
1.Is it possible to explain the AIR,VARY and SUB band of this EQ??when I change the VARY I can't understand exactly what happened.VARY and AIR are related to each other??I mean the frequency of AIR band choose by the VARY selector??or vary is a shelve??

2.and the sub band is a band under 40HZ??

3.It seems that the Q of this EQ is very wide, isn't it??

thanks :)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Anthropic on August 03, 2013, 07:03:00 PM
Thanks for your responses and help.  I ended up grounding the PIN 1s of the XLR IN/OUT to chassis at entry.  I left the shields of the internal cables attached to the ground holes on the INs/OUTs of the EQ board.  I also grounded the -+18 ground on the EQ boards directly to star/chassis ground.  The ground hole on the "output" of the PSU board was left unconnected.  This seems to be the most effective grounding scheme so far. 

Unfortunately, I'm now realizing that the vast majority of the hum is coming from the toroidal power transformer (as it is almost twice as loud in the EQ board closest to it).  I've rotated the transformer to the position that produced least hum but, even there, it produces hum that makes the EQ completely unusable. 

The only real solution seems to be mounting the PSU outside the case, which becomes another pain.  Oh well...  I guess I'll have to put this project aside for a while.   :( 
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on August 05, 2013, 01:42:10 PM
..the vast majority of the hum is coming from the toroidal power transformer..
..that would have a VA rating and secondary voltages printed on its label as well as indicators to identify the start of each secondary winding, if you don't have the manufacturers part ID to look up the datasheet. Colour coding of transformer wires is not standarized. Source of your hum might come from an out-of-phase series connection of your secondary windings, if your transformer isn't already a center tapped transformer.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on August 05, 2013, 01:58:29 PM
when I connect output of EQ to input of my speakers with TS cables,I hear a little bit of distortion!!but when I connect the output to a headphone,there is no distortion.what is the reason for that?should I use TRS cable only??
Speaker?Headphone? This is an EQ, not a power amplifier. When using TS cables for an unbalanced connection to your assumed monitor- or headphone amplifier, set the jumpers on pcb for unbalanced connection, else you nearly short out the summing stage U5. This will cause more than 'a little bit of dirtortion'.

Quote
1.Is it possible to explain the AIR,VARY and SUB band of this EQ??when I change the VARY I can't understand exactly what happened.VARY and AIR are related to each other??I mean the frequency of AIR band choose by the VARY selector??or vary is a shelve??
2.and the sub band is a band under 40HZ??
3.It seems that the Q of this EQ is very wide, isn't it??
Already answered, just read this thread...

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Anthropic on August 05, 2013, 10:55:05 PM
..the vast majority of the hum is coming from the toroidal power transformer..
..that would have a VA rating and secondary voltages printed on its label as well as indicators to identify the start of each secondary winding, if you don't have the manufacturers part ID to look up the datasheet. Colour coding of transformer wires is not standarized. Source of your hum might come from an out-of-phase series connection of your secondary windings, if your transformer isn't already a center tapped transformer.

Interesting.  I'll try swapping the connections and see if it has any effect.  Thanks for the tip!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on August 06, 2013, 05:55:24 AM
I'll try swapping the connections and see if it has any effect.
??? Didn't say so, but as long as you keep your transformer data and how you connected it a secret, noone could seriously help you.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Anthropic on August 06, 2013, 08:18:22 PM
Oops, sorry Harpo.  I'm using a Toroid-brand transformer, model #602.152.  It's 0-15V, dual secondary, rated for .80A per secondary.  Right now, I have it wired with BROWN and ORANGE together to the GROUND of the PSU (as a pseudo center tap)(with a third wire which goes to star ground), while the RED and YELLOW secondaries each attached to a respective AC input on the PSU.  Previously, I had RED and ORANGE twisted together and attached to the GROUND input on the PSU (also with a third wire to star ground) and YELLOW and BROWN each separately attached to one of the AC inputs on the PSU. 

Both configurations had a high level of stray field buzz injected into the EQ boards.  To confirm this, I unbolted the transformer and lifted it out of the chassis (as far as it could go with the wires still attached).  As I moved it around, I could find areas and positions where the buzz diminished considerably.  However, none of those positions lent itself to convenient mounting.  Furthermore, no position was able to diminish the buzz to a level at which the EQ could be usable. 

As an aside (due to other posts mentioning this), I've measured the resistance of each of the chassis panels to star ground and none measures more than 1 Ohm (most, if not all, were below 0.5 Ohms).  Accordingly, I'm doubtful that the Faraday-cage-like effect of the chassis is compromised in any way.

To further muddy the waters, another pair of Night EQs I am building at the same time used a different brand/model of toroidal transformer.  That transformer is an AMVECO 62063-P2S02 (25 VA, dual 15V secondaries).  This transformer has much less buzz induced in the EQ boards, but is still not quiet enough for use. 

Anyway, I hope this makes my problem a little clearer.  Thanks for the attempts to troubleshoot this one.

Dan
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on August 08, 2013, 08:04:41 AM
The 'Toroid Corporation', model #602.152 (http://www.toroid.com/standard_transformers/rectifier_transformers/DataSheets/602.152.pdf) should either have red+orange joined for the center tap or brown+yellow joined for the center tap connection. Rotating the toroid for least induced hum (50Hz/60Hz) should help a little. For usual the greatest radiated field is where secondary wires leave the toroid, so get this spot furthest apart from high impedance areas on EQ-pcbs. Distance is your friend. (If your induced hum is at dominant 100Hz/120Hz instead, source of hum mostly will originate from PSUs diode snap.) Bolting some vertical metal shield between toroid/psu and the eq-circuit and distant placing of AC-mains wires should further help.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dogma on August 14, 2013, 02:21:27 AM
Sorry about coming in late - I was hoping that someone might be Ble to confirm if this is the same as on gustav s site? I'm looking for a mouser bom for that build and can't locate one. Some assistance would be SO appreciated
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on August 14, 2013, 04:14:57 AM
I was hoping that someone might be Ble to confirm if this is the same as on gustav s site?
Colins version (PCBs from Gustav) base on a partly similar circuit with different behaviour in a different format,
whatever the meaning of 'Ble' (bloody low educated?) might be.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: imloggedin on August 16, 2013, 10:47:35 AM
Will this transformer: http://www.parts-express.com/pe/showdetl.cfm?partnumber=122-605 work with the power supply board? Its 30VA.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on August 16, 2013, 03:19:32 PM
That transformer should be fine.

Peter
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: imloggedin on August 16, 2013, 04:26:53 PM
Thanks Peter,

Whats all this:  "Cbyp Cbyp Cbyp Cbyp Cbyp1 Cbyp10 Cbyp2 Cbyp3 Cbyp5 Cbyp6 Cbyp7 Cbyp8" in the parts list. I don't see any capacitors like that anywhere in the schematic.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: kooma on August 21, 2013, 05:42:06 AM
almost ready
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: kooma on August 21, 2013, 05:42:47 AM
and finished:)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on August 21, 2013, 06:51:46 AM
Quote
Whats all this:  "Cbyp Cbyp Cbyp Cbyp Cbyp1 Cbyp10 Cbyp2 Cbyp3 Cbyp5 Cbyp6 Cbyp7 Cbyp8" in the parts list. I don't see any capacitors like that anywhere in the schematic.

These are PSU bypass caps.

Peter
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on August 22, 2013, 07:58:57 AM
Any prospect of another run of pcbs? I'm really keen to build one of these but can't track down any boards. Cheers
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: seavote on September 02, 2013, 12:17:11 PM
small bear (supplier in US) has rt angle pc mount 1000k reverse audio pots. no 500k as needed for nite EQ. is there any reason not to order 1000k pots and strap a 1000k resistor across the lugs of the 1000k pot to make my own 500K reverse pot. is there something im not thinking of . seems like a simple solution to me if not. 8) 8) 8) 8) 8) 8) 8) 8) 8)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on September 02, 2013, 03:42:00 PM
small bear (supplier in US) has rt angle pc mount 1000k reverse audio pots. no 500k as needed for nite EQ. is there any reason not to order 1000k pots and strap a 1000k resistor across the lugs of the 1000k pot to make my own 500K reverse pot. is there something im not thinking of . seems like a simple solution to me if not. 8) 8) 8) 8) 8) 8) 8) 8) 8)
The rheostats unity gain setting would be at about 65%, not 50% turns angle. You could use paralleled 1M stereo rev.log.pots instead, if avail.
Not that much redesign needed to use lower value pot/rheostat values than 500K.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on September 02, 2013, 07:45:39 PM
Thanks for your responses and help.  I ended up grounding the PIN 1s of the XLR IN/OUT to chassis at entry.  I left the shields of the internal cables attached to the ground holes on the INs/OUTs of the EQ board.  I also grounded the -+18 ground on the EQ boards directly to star/chassis ground.  The ground hole on the "output" of the PSU board was left unconnected.  This seems to be the most effective grounding scheme so far. 

Unfortunately, I'm now realizing that the vast majority of the hum is coming from the toroidal power transformer (as it is almost twice as loud in the EQ board closest to it).  I've rotated the transformer to the position that produced least hum but, even there, it produces hum that makes the EQ completely unusable. 

The only real solution seems to be mounting the PSU outside the case, which becomes another pain.  Oh well...  I guess I'll have to put this project aside for a while.   :(

Get a sheet of mumetal shielding, its self adhesive... cut a strip large enough to wrap around the whole toroid. The stuff is amazing, I had a strong hum on one of my g-pultecs, didn't matter where I put the toroid. Once the sheilding was there the hum was gone entirely.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: fazeka on September 19, 2013, 02:04:58 PM
Hi,

Long time member only getting 'round to starting on this project now.

Question about the stepped Lorlins with this project and gain.

I am probably going to use the 12-position Lorlins as there is no seemingly affordable rotary switch readily available.

The gain of each frequency on the original is +/-15dB.

Using Harpo's stepped pot calculator, that means 3dB increments. Seems like more than I'd like per step.

If I go +/-10dB, I get 2dB increments per step. But is 10dB going to be enough? IOW, will I likely ever have a need for more than 10dB?

What have others found as the best compromise?

Thanks,
Chris
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on September 19, 2013, 02:52:03 PM
I'd say 2dB steps might be fine, owing to the wide Q of the bands.

I have very rarely done huge cut or boost settings on mine.

Peter
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: fazeka on September 19, 2013, 04:30:22 PM
Thanks Pete!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on September 29, 2013, 09:17:49 AM
Hey Guys,
I just finished building a pair of these.. great sounding units and my first self-etch project... nice design for first time etch as well...

Anyhow - has anyone experienced a 'squealing' sound when maxing out the 2500k band or the HI-SHELF band ?

As soon as I wind the pots back a tiny bit on either of these pots the 'squealing' stops. Both bands sound like they are working fine though and the problem immediately disappears if you turn back the pots a little...

I don't have this issue on any of the other bands.

I was thinking maybe something to do with the inductors, but I can't see any issues there. Its more of an annoyance than anything and in my limited testing it doesn't appear to cause any other issues.

Interested to hear if anyone else experienced this?
Title: nite eq done
Post by: dribro on September 29, 2013, 12:10:38 PM
hi

thank you all, especially to Peter for this great project. Got it up and running from first try. Sweet sounding unit, very good indeed! Now it's time to finish the second one!

best,
Adriano
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bieckmusic on September 30, 2013, 09:19:29 AM
Hi frazzman, congrats.   :)  I didn't have squealing on my unit, is it on both channels?  On my self-etch I reinforced some traces with solid core wire, because eq bands were cutting in and out.  A few hours with the continuity checker and I figured it out.  Self-etching was a blessing and a curse... 

I had squealing come up on the optical desser I built, only when I cranked the threshold all the way up, some high frequency oscillation...  I too wonder what causes high frequency oscillation?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on September 30, 2013, 10:01:18 PM
Hi frazzman, congrats.   :)  I didn't have squealing on my unit, is it on both channels?  On my self-etch I reinforced some traces with solid core wire, because eq bands were cutting in and out.  A few hours with the continuity checker and I figured it out.  Self-etching was a blessing and a curse... 

I had squealing come up on the optical desser I built, only when I cranked the threshold all the way up, some high frequency oscillation...  I too wonder what causes high frequency oscillation?

Hi Bieck, thats for the reply! Channel 2 isn't finished yet so I can only confirm on channel 1 for now. I do have a couple of tracks that aren't as thick as I'd have liked (when compared to a commercially produced PCB). I did use a DMM to measure continuity across and 'suspicious' areas to make sure that the circuit wasn't broken anywhere due to thin tracks, but everything checked out.

As I said, its only on the 2500k and Air band, with either pot maxed out that I get the squealing... soon as I turn the pots back a notch it goes away, the boosts on both bands seem to be working fine though... I can hear the obvious high end boost.
Anyway... its really odd, I thought maybe it was due to the inductors, I removed them and bridged the gaps with resistor legs, it didn't really make a difference for better or worse.
I suppose I could live with the issue as it doesn't have that much of an impact but it is damn annoying. I went through this entire thread but no one else mentioned it. I'll see what happens with channel 2.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bieckmusic on September 30, 2013, 10:17:10 PM
You know, maybe, it could be the end of a cap on the 2500k part of the circuit.  If you trace it from the pot back and check all the caps???  I read somewhere that un-grounded filter caps can cause this, ...   anyway good luck, I love my nite eq!  trouble shooting has been helping me understand these circuits.  Also you could try and relocate the torroid or the power supply wires away from the board??

I think it's totally worth it to get all the bugs out, otherwise it just drives me nuts   :) :) :)

best,
greg
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on October 01, 2013, 01:15:46 AM
You know, maybe, it could be the end of a cap on the 2500k part of the circuit.  If you trace it from the pot back and check all the caps???  I read somewhere that un-grounded filter caps can cause this, ...   anyway good luck, I love my nite eq!  trouble shooting has been helping me understand these circuits.  Also you could try and relocate the torroid or the power supply wires away from the board??

I think it's totally worth it to get all the bugs out, otherwise it just drives me nuts   :) :) :)

best,
greg

Hi Greg,
Thanks for that, sounds like a good place to start. I'll have a look around C51 and C3 as per the schematic these are the caps in the 2500k boost section. I understand that the air band and the 2.5k band are interrelated so one could therefore impact the other.
I haven't properly grounded everything yet as the unit is still out on the test bench before I finally rack it, so its therefore possible that the filter caps aren't grounded properly... So far its a great sounding EQ
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on October 02, 2013, 08:37:37 PM
  I read somewhere that un-grounded filter caps can cause this, ...

You're the man Greg! This is exactly what the issue was. Now with proper grounding, there is no noise or squealing at all on the 2.5k and AIR bands.

This is an awesome sounding unit!

Thanks for your help.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bieckmusic on October 02, 2013, 08:55:46 PM
No problem,  way to go, so glad it works!!     :)

I love my eq too, I think I'm going to add a pair of these meters.  More colored flashing lights!! 

http://fivefishstudios.com/component/content/article/56
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on October 03, 2013, 09:55:17 AM
No problem,  way to go, so glad it works!!     :)

I love my eq too, I think I'm going to add a pair of these meters.  More colored flashing lights!! 

http://fivefishstudios.com/component/content/article/56

Cheers mate! First self etch too... Worked a treat

I reakon you could etch up a few of those vu boards , not much to them, they would sure look cool but $19 for a few led's and a meter driver ic ain't that cheap!! Good luck with your additions
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Bonsaimaster on October 31, 2013, 07:15:20 PM
Ok I built one of these NITE EQ 500 Series. But don't know how to calibrate it. Also do not know where pin 1 is on the 26 way upper deck. Also there are test points and a variable trim but no reference for testing. Any help appreciated.

Bonsaimaster
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Bonsaimaster on October 31, 2013, 07:16:05 PM
Ok got sound to go thru the unit but cannot get the EQ to kick in.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on November 02, 2013, 12:45:57 AM
@Bonsaimaster, wrong thread for different circuit (schematic and operating behaviour)
with unit powered (inside your 500 rack or using a cardslot extender), bypass switch pushed to 'In' (red LED is shining), Air switched to 'off' and all level pots centered,
feed unit with 1V rms signal at a frequency your multimeter can handle, maybe 100Hz (IE measuring AC voltage between TP4/5 will show 1.000VAC). Confirm readout at TP2 for 0.039VAC in respect to 0V reference voltage (TP11) after debalancing stage and voltage divider R36/R24. Adjust trimmer R41 for a 0.500VAC readout at TP3 in respect to 0V reference voltage (TP11). Confirm readout of 1.000VAC after balanced line driver between TP6/8. Done.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Bonsaimaster on November 03, 2013, 10:33:49 AM
I am getting .122V between TP4 and TP5 so something is wrong and nothing between TP2 and TP11.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on November 03, 2013, 01:52:43 PM
I am getting .122V between TP4 and TP5 so something is wrong and nothing between TP2 and TP11.
So you either didn't feed it with 1VAC between XLR-pins2/3 or something is wrong with your ribbon connection. Have a look at the schematic and just follow the traces to make sure you connected it correctly.
With 0.122VAC between TP4/5, TP2/11 should read 0.005VAC (or 0.004758V if your meter could do it and your attached measuring wires doubtfully don't pick up any garbage), not dead zero, so there might be more wrong. What are the supply voltages at NE5532-pins 4 and 8 in respect to TP11 ?
For your Bypass/active LED not showing up, you simply might have fitted the LED the wrong way round. The LED will still be alife. Other polarized parts might/will not be that forgiving, once powered with wrong orientation.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: shot on November 24, 2013, 11:43:01 AM
Please help me out with this!

I've stuffed two Peter's pcbs. Also I made my PSU based on LM317/337 regulators, self etched it.
I've calibrated PSU to give +18V and -18V before connecting the EQ board.

On first EQ power up there was smoke from 22R resistors near the power rail connector. I immediately turned it off so I wasn't able to spot where exactly smoke came from. Then I took out all the ICs and measured DC resistance between +18V header and opamp socket pin 8 (or pin 7 if it's 5534). It's 22R as it should be.
I've checked for some solder blobs, cleaned all again with isopropylene and checked to see DC resistance between + and - headers (without PSU rail wires connected). It measured roughly around 1M6. That's supposed to be okay, I guess.

Then I applied power again.
There was no smoke this time.
But I noticed that bypass caps CPSUb1 and CPSUb2 are starting to grow on top. Ready to explode I guess. So I turned off the power.
I've checked again the DC resistance between + and - rails, but this time with screwed wires from my PSU board. Now I measure around 6K DC resistance! Is that normal? I've powered up the PSU again without it being connected on EQ board and DC voltages remain correct. But this seems as a fairly low resistance, am I correct? Could that be the reason for bypass caps (almost)blowing?

What is the next step I should do?
My noobish brain is left without ideas...

I've attached the psu schematic I used to build my psu, and my board layout (single layer) if that helps...
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on November 24, 2013, 12:30:15 PM
On first EQ power up there was smoke from 22R resistors near the power rail connector...
...But I noticed that bypass caps CPSUb1 and CPSUb2 are starting to grow on top. Ready to explode I guess...
What is the next step I should do?
Unsolder and replace the blown from probably reversed orientation or insufficient voltage rating 47uF/35V caps CPSUb1 and CPSUb2. (if CPSUb3 and CPSUb4 are fitted with same reversed orientation as CPSUb1 and CPSUb2, unsolder and replace as well.) Caps positive leg goes in the rectangular shaped solder pad. Double check for 22R resistor values of all 4 RPSUs with PSU disconnected. They might be still alife or blown from excessive current demand of reversed fitted polarized caps.
Good luck
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: shot on November 24, 2013, 01:18:42 PM
I have replaced all PSU bypass caps. They were underrated (25V) but were oriented correctly, and I've replaced them with 35 volt rated ones.
Now when powered up without ICs, everything is ok. Voltages on the IC sockets are correct.
When ANY IC is inserted RPSU resistors start smoking! Now I'll replace those since they dropped in value and got a black burnt trail on them.
I can't imagine all of my ICs are faulty! That would statisticaly make no sense!
And I triple checked IC orientation - its good.

Is it possible 1/4W rating of RPSU resistors is underrated? If I replace them with 0.6W ones will that help?

Thank you Harpo for helping me with this! Please stay with me! :)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: shot on November 24, 2013, 02:01:12 PM
 :-[ SELF-PUNISH   :-[ SELF-PUNISH!!

Damn how emmbarrassed I am now...

I found out what was wrong!

I mislabeled + and - wires!
Wrote wrong designations on small tape labels!

DAMN!

Excuse my stupidity!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bieckmusic on November 25, 2013, 08:33:45 PM
hey shot,

Sounds like you're standing in front of the butt-kicking machine with a handful of quarters.   :)

It happens all the time glad you found it!!

 :)

Greg
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: shot on November 26, 2013, 03:32:14 AM
Yeah! I try to be as detailed as possible and this is something I never imagined could happen. A flick of a second when writing labels and there it goes. Damn!
 :-[
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on November 30, 2013, 07:24:54 AM
So hypothetically, if I left a pot disconnected from the circuit - what would we expect the result to be - for example if the 40hz pot was omitted would this frequency sit at 0db, -5db etc. will there be a boost/cut effect with a pot omitted ? Reason I ask is I managed to mess up a few pots in the process of trying to jam them into my very congested front panel real estate and now I'm waiting for some new ones from aml. In the meantime I left out the damaged pots but the circuit sounds like it's lost a bit of low end - at the moment the sub pots are disconnected and 650hz on the right channel. Any thoughts ?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on November 30, 2013, 08:44:18 AM
Cut effect for the omitted bands. Substitute the omitted variable resistance (the 470K rev.log. pot wired as rheostat) by 47K...50K resistor.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: pieca on November 30, 2013, 11:51:51 AM
hi!

I'm following actively this topic from weeks…

This is my build :
(http://pierre-caillet.fr/eq3/eq3-1.jpg)

All pots are stepped with 0.5 Db steps with 23p rotary switches (from -5.5Db to +5Db). Thanks harpo for your exell file  :D

I don't know if it works yet… I have to bring it to the studio for test, but so far so good : no smoke yet  ;D

I have also to deal with the amber led's resistor values, they are killing my eyes (no issues with the red ones)


I'm planing to add the overload circuitry from there  (thanks harpo again) :
http://www.khstudio.us/DIY%20PICs/CLIP%20CIRCUIT.bmp

just got a question :
on the peak schematic, signal is taken after pin 7 of U4
on my board done with Petter Cornell's PCB V2 1-6-7 it seems that the only pin 7 going to 470uf condenser ant then a 47r resistor (R29) is U6…
Anyone ever implement clip circuitry in their build?
Any help will be really appreciated!


Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on November 30, 2013, 01:15:46 PM
I have also to deal with the amber led's resistor values, they are killing my eyes (no issues with the red ones)
increase current limiting resistor to decrease current flowing for your probably amber high-efficiency-LED.

Quote
on the peak schematic, signal is taken after pin 7 of U4
on my board done with Petter Cornell's PCB V2 1-6-7 it seems that the only pin 7 going to 470uf condenser ant then a 47r resistor (R29) is U6…
Either after DC blocking 470uF cap connecting to pin6 of the NE5534 summing amp or after corresponding cap connecting to pin7 of the following NE5532 inverter.
Consider to increase the value of R200 in order to decrease sensivity of the clip indicator circuit.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: pieca on November 30, 2013, 01:54:24 PM
Consider to increase the value of R200 in order to decrease sensivity of the clip indicator circuit.
I've read somewhere in this post than the original R200 value was 46.4K instead of 4.64k, will try to start with this…
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on November 30, 2013, 09:43:36 PM
Cut effect for the omitted bands. Substitute the omitted variable resistance (the 470K rev.log. pot wired as rheostat) by 47K...50K resistor.

Thanks Harpo.

Also - if I had a level difference present with both channels are engaged, where would be the place to start? Is there a resistor I can change to try and match the levels. From what I can tell it looks like left channel is 3db louder than right. I will do some more testing when the new pots arrive. Both channels are level in bypass though. Cheers
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on November 30, 2013, 11:19:11 PM
Also - if I had a level difference present with both channels are engaged, where would be the place to start? Is there a resistor I can change to try and match the levels. From what I can tell it looks like left channel is 3db louder than right. I will do some more testing when the new pots arrive. Both channels are level in bypass though.
3dB difference only in bypass mode? tweak R48 for input level=output level. 3dB difference in both bypass mode and all bands centered for +/-0dB? tweak R30. If this level imbalance is frequency dependant, look out for same resistor and cap values at the bandwidth limited gain stages.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on December 01, 2013, 12:46:35 AM
Also - if I had a level difference present with both channels are engaged, where would be the place to start? Is there a resistor I can change to try and match the levels. From what I can tell it looks like left channel is 3db louder than right. I will do some more testing when the new pots arrive. Both channels are level in bypass though.
3dB difference only in bypass mode? tweak R48 for input level=output level. 3dB difference in both bypass mode and all bands centered for +/-0dB? tweak R30. If this level imbalance is frequency dependant, look out for same resistor and cap values at the bandwidth limited gain stages.

Thanks Harpo, sorry to clarify the level difference between channels is not in bypass but when both channels are engaged. It isn't frequency dependent. Do the same principals apply ? I had checked each resistor value for each channel when stuffing but there is apparently some difference resulting in the level difference. I checked the balanced/unbalanced jumpers too and both channels have the expected cutting / boosting behaviour
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on December 01, 2013, 09:35:41 AM
..the level difference between channels is not in bypass but when both channels are engaged. It isn't frequency dependent.
with missing pots substituted by prementioned resistors ? The stages in this 'EQ' are not filters but bandwidth limited gain stages that get summed up to a more or lesser degree to recombine for the complete audio band. If one band would be missing, this would explain the L/R imbalance, but this would be frequency dependant with most impact at the center frequency of the one side missing band. Is the sum of each half rotation rev.log.pot value + 5K62 series resistor for the +/-0dB setting the same as value of R30 ?
Quote
Do the same principals apply ?
Yepp.
Quote
I checked the balanced/unbalanced jumpers too and both channels have the expected cutting / boosting behaviour
balanced/unbalanced jumpers mixed up would be 6dB difference, not 3dB.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: shot on December 05, 2013, 05:40:11 AM
Hey guys... another problem...

I've almost finished my build. Signal passes through, SNR is cca -100db (100hz peak, 50hz waaay below), works almost like charm!

But there's big difference in boost and cut. And it happens on all bands, both channels!
Boost is cca +16db
Cut is cca -4db

I've checked Rseries resistors and their values are good.

Where else to look?

:)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: iprovlek on December 05, 2013, 05:49:37 AM
Great unit Shot!

And front panel is great....

I think that the sound is great!
 ;)

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: shot on December 05, 2013, 03:56:55 PM
Thanks! (Hvala Igore!)

Front panel is some sort of thick foam-ish material. I don't know it's name.
I went to buy colored plexyglass but ended up with this for cheap.
Print is regular toner transfer, same as if I was doing pcb's.
And it's acryllic varnish to protect the surface.
It's all DIY!
And the rest is... momentary switches from Studer's unknown module, my design for the flip-flop pcb to control relays that do bypass switching and turn lamps in momentary switches... and PSU... is just PSU...
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: pieca on December 08, 2013, 04:34:18 AM
hi everyone,

I need some clarifications about stepped pots and Harpo's exell sheet.
I've read all the posts, but it is not really crystal clear for me…

with stepped pots, I need to bridge all "max boost" resistors from the board (R37,39,41,43,45)

what about "max cut" resistors (R36, 38, 40, 42 44) ? Must I let them or bridge them too?

Thanks for your help  :)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on December 08, 2013, 06:00:59 PM
with stepped pots, I need to bridge all "max boost" resistors from the board (R37,39,41,43,45)
From excel sheet 'to substitute Rseries+RV' shouldn't leave a question remaining.
Quote
what about "max cut" resistors (R36, 38, 40, 42 44) ? Must I let them or bridge them too?
These are not R36,38,40,42,44 but the pots RV36,38,40,42,44.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: shot on December 09, 2013, 03:02:49 PM
Maybe my post few days ago went under the radar...

So i humbly BUMP my question...

Can anyone help me to find the cause why my unit is boosting +16db and cutting only 4db?
On all the bands of two boards it's doing the same thing....
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on December 10, 2013, 06:46:44 PM
Can anyone help me to find the cause why my unit is boosting +16db and cutting only 4db?
On all the bands of two boards it's doing the same thing....
This 'EQ' (it is a frequency band split summing circuit) isn't cutting like a usual filter. Non-inverting bandwidth limited gain stages don't fall below unity gain. It is the lesser boosting that is perceived as cut and this 'cut' has limits for prementioned reason.
Double check parts values and orientation. Jumpers set correctly ? Common to both boards probably will be a wrong not band specific parts value, wild guessing maybe the voltage divider R25/R24 after the debalancing stage, wrong value and/or wrong taper pots and missing or wrong output stage jumper setting. Maybe it is only me, but from your build pic I couldn't identify a single parts value and a blurry pic will only get you a blurry answer.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: shot on December 10, 2013, 07:39:01 PM
Yes, I was also thinking that it must be some resistor or other element with wrong value.
I started checking but so far haven't found any misplaced value. Went through output part (from where EQs and bypass come together) till the output, but no luck yet. Tomorrow I'll check the rest of it.

Pics came from my mobile phone so they are too blurry. I'll try to take better pix.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: kogstudio on December 11, 2013, 06:00:21 PM
Hey does anyone have a link and/or part # for the type of knobs that were used on the original nightpro eq3d?
I.e. the coloured top ones?
like on this page (but not for the small yellow one, I'll keep them all the same size)
http://www.pixelproaudio.com/used/mic-preamps-eqs/used/nti-nightpro-eq3d-equalizer.html

Any info much appreciated :)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: pieca on December 13, 2013, 09:30:19 AM
Hi,

I've got some issues with my build and stepped pots…
I'm using 23 steppes rotary switches  with resistor calculated with harpo's exell file
R37, 39, 41, 43, 45 are bridged
R30 is 56200 ohms
According to the exell file, my switches are going from 105K (-5 Db) to 30K1 (+5.5 Db) center position  (0db) is 56K2
all my resistors are 1% and were measured before soldering

After measures, this is my results :

with all pots centred, I'm not flat…
pots centered :
(http://s18.postimg.org/wws3hfpo9/Flat.png)

Bypass :
(http://s13.postimg.org/5hcpxuamv/Bypass.png)

for sub, 40Hz and 160 Hs pots, i've got something like -2 Db @105k to +2 Db @ 30K1

For 650 Hz : -1.5 Db to +2.5 DB

For 2500K : -2.5 Db to +3.5 Db

For the Air band (all frequencies): from +2.5 Db (105k min position) to +7 Db (30K1 max position)

is everything normal or did i missed something?
I'd prefer not un solder 276 resistors and solder 276 new resistors again…

Thanks for your help

EDIT : same behavior with both channels
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on December 29, 2013, 04:53:37 AM
Hi all,
Does anyone have any test sweeps of their completed nite eq builds ? My unit just doesn't "sound" right. When I throw it on the mix bus it sounds a bit "flat", to my ears it sounds a bit like I'm loosing some low end punch, then when I bypass or remove the insert the mix immediately sounds "fuller" again. From what I can tell, all bands on both channels are boosting and cutting correctly.

My testing is with the eq engaged, all pots set to 0 (center indent) , air band off.

I've done some testing using RMAA. This is what the plot of my right channel looks like. Left looks pretty much the same too. The curve is not overly flat, there's a roll off to 40hz, which may account for some loss in the lows, does this look right???
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on December 29, 2013, 05:39:44 AM
Just a second thought ... I just realised I did substitute a number of resistors in the circuit (particularly the precision values around the potentiometer sections on the PCB) that were hard to come by - I.e. I used 20k instead of 20k5, 1.2k instead of 1k27... So if I were to change all the resistors around the potentiometer sections to the precise resistor values would this bring me closer to a flat response ? This is the only thing I can attribute to the circuit not "sounding right"
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 03, 2014, 08:39:56 AM
Hey all,
Still fighting with this build a little bit, appreciate if someone has any input they can offer.

After more testing, it has become apparent I have about a -2db cut @ 40hz on my right channel with EQ engaged and all pots set to 0 (center ident).

Any ideas what could be causing this only on 1 channel? I've checked for shorts and correct component designations. I also replaced the SUB and 40hz pots as there was a fair bit of cramming to fit all these pots on the front panel but it didn't have any impact. I am getting cutting and boosting action on sub and 40hz bands but for some reason when set to 0 I am seeing this dip.

This is my main issue...

The other issue is that with the EQ engaged and all pots set to 0, the frequency curve is not the same as when bypassed, It is almost totally flat in bypass. As I noted earlier, I substitued resistors around the pots section, i.e. 20k instead of 20k5 etc, so I am guessing this is the contributing factor to that issue? I am going to substitute these resistors for exact values.

This still won't fix my 40hz @ -2db cut issue, can anyone offer any advice? I've attached plots in both bypass and with eq engaged and all pots set 0. Thanks a lot
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 03, 2014, 08:40:28 AM
And again in bypass... no issues there
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on January 03, 2014, 10:01:49 AM
..with EQ engaged and all pots set to 0 (center ident).
These pots with neg.log taper for usual come with +/-20% tolerances. You want the half rotation mechanical center about 10% of its stated value, so this half rotation value + series resistor = value of summing amps feedback resistor. I have an excel file posted earlier in this thread to fix this tolerance related behaviour with hopefully least efford. (and this is a different subject from frequency bands not being exactly 2 octaves apart for the remaining bumps. Next to other improvements this would be a non issue with derived bands, but the OP insisted on keeping it close to the original, at least it was his thread).
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 03, 2014, 05:26:42 PM
..with EQ engaged and all pots set to 0 (center ident).
These pots with neg.log taper for usual come with +/-20% tolerances. You want the half rotation mechanical center about 10% of its stated value, so this half rotation value + series resistor = value of summing amps feedback resistor. I have an excel file posted earlier in this thread to fix this tolerance related behaviour with hopefully least efford. (and this is a different subject from frequency bands not being exactly 2 octaves apart for the remaining bumps. Next to other improvements this would be a non issue with derived bands, but the OP insisted on keeping it close to the original, at least it was his thread).

Hi Harpo,
 Thank you for your reply. I know I have two separate issues, one being the -2db 40hz~ cut and the other being that the freq curve isn't flat with pots centred. The 40hz~ cut doesn't seem to be related to the tolerance of the pot(s) as replacing it with another pot nets exactly the same result.

I found your excel file which will help perfectly for offsetting tolerance around center ident variations, but what about the 2db cut on my right channel, this is independent of the pot. Thanks again
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on January 03, 2014, 06:39:07 PM
double check real world parts values of R18, R20 and R43.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 04, 2014, 01:27:37 AM
double check real world parts values of R18, R20 and R43.

Thanks Harpo, already checked but I just pulled the resistors from the board and rechecked, they were all within a 5-10% tolerance, this time I even soldered on series some extra resistors to get the values near dead on with the design, but no luck.
Is there anywhere you can think of that a short could exist and result in this issue? Also, could it possibly be an issue around the sub band ? I didn't think so as the frequency plot indicates it's around 40hz but I was wondering if the sub and 40hz band are related in that sense? Thanks again

Edit: maybe a slack workaround but would changing the value of the 5k62 resistor help get me to 0db ?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on January 04, 2014, 09:17:33 AM
Is there anywhere you can think of that a short could exist and result in this issue?
a short between opamps output and non-inverting input (unity gain follower) would be missing the LPF part and drop in level would be higher. Same with shunt arm open circuit for the HPF part from overheating caps (you'd have to fry both caps by too long soldering. Only one dead cap would shift frequency response one octave up, not two), so this would be a more unlikely reason.
Quote
Also, could it possibly be an issue around the sub band ?
easy enough for you to double check the 10Hz band with the pcb right before your eyes...
Quote
maybe a slack workaround but would changing the value of the 5k62 resistor help get me to 0db ?
decreasing R43 will get you closer, but the peak in the center of the dip will be boosted as well.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 04, 2014, 09:32:57 AM
Is there anywhere you can think of that a short could exist and result in this issue?
a short between opamps output and non-inverting input (unity gain follower) would be missing the LPF part and drop in level would be higher. Same with shunt arm open circuit for the HPF part from overheating caps (you'd have to fry both caps by too long soldering. Only one dead cap would shift frequency response one octave up, not two), so this would be a more unlikely reason.
Quote
Also, could it possibly be an issue around the sub band ?
easy enough for you to double check the 10Hz band with the pcb right before your eyes...
Quote
maybe a slack workaround but would changing the value of the 5k62 resistor help get me to 0db ?
decreasing R43 will get you closer, but the peak in the center of the dip will be boosted as well.

Thanks Harpo, I'll need to look at this closer, I've been working on the right channel far too long so I decided to leave it for a while and start fixing up the left channel based upon your spreadsheet (wish I had have seen it first time round...). I wanted to adjust the resistor values on each band to try and get 0db center ident for each freq...

Based upon your spreadsheet, I ended up with the following values:

SUB = R pot total: 445,000, R pot center: 56,300, R series: 10,470
40Hz = R pot total: 472,000, R pot center: 54,500, R series 12,270
160Hz = R pot total: 483,000, R pot center: 56,600, R series: 10,170
640Hz = R pot total: 451,000, R pot center: 54,100, R series: 12,670
2.56 Khz = R pot total: 481,000, R pot center: 60,700, R series: 6,070

R fb = 66,770

Since the R series values are so 'irregular' I had to put a few resistors in series to get to the desired values. I replaced R30 & R48 with a 68k resistor (closest to 66770ohms I had) - is there any impact not using an exact value for R30 & R48? The only audiable effect I can hear is that the output is slightly hotter than before

Attached is my frequency response after these resistor value changes, its certainly better but far from flat... I am starting to think that trying to get the center ident to track perfectly at 0db is not a worthwhile exercise. I wanted to use this EQ in a mastering chain but I don't think i'm going to get its response flat enough. The low end roll off seems really unusual too.

How does the plot for the left channel look? Am I being pedantic or have I missed something / misinterpreted your instructions?

Back to working on Right channel later today.... sorry for all the long winded questions
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on January 04, 2014, 10:40:12 AM
How does the plot for the left channel look?
bumpy road. As previously said, center frequencies between these bandwidth limited gain stages have to be exactly two octaves apart, IE 10,40,160,640Hz and this being a different subject from gain setting. FI your '640 Hz' band looks too high frequency, resulting in a dip below and a peak above this frequency band. With schematic parts values this will result in too low 626.6Hz. Using higher tolerance resistor parts (IE 1K2 instead of 1K27 from schematic) will result in too high 663.1Hz on paper. For the wanted 640Hz and assumed perfect corresponding caps, resistor values needed are 1K243 for R14 and 124R3 for R12 for this band.
Tweaking the series resistor will not fix this behaviour.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 06, 2014, 08:11:49 AM
How does the plot for the left channel look?
bumpy road. As previously said, center frequencies between these bandwidth limited gain stages have to be exactly two octaves apart, IE 10,40,160,640Hz and this being a different subject from gain setting. FI your '640 Hz' band looks too high frequency, resulting in a dip below and a peak above this frequency band. With schematic parts values this will result in too low 626.6Hz. Using higher tolerance resistor parts (IE 1K2 instead of 1K27 from schematic) will result in too high 663.1Hz on paper. For the wanted 640Hz and assumed perfect corresponding caps, resistor values needed are 1K243 for R14 and 124R3 for R12 for this band.
Tweaking the series resistor will not fix this behaviour.

Thank you Harpo, I managed to fix the troublesome 40hz-ish dip, looks like there was a dry joint on one of legs of a cap on the 40hz band, not sure but I reheated all joints in this section and the fault is gone.

So I ordered precision value resistors (0.1%) tolerance, inline with the values in the schematic - so I take it that once I replace all higher tolerance resistors currently fitted, and then change series resistors inline with the center point measurements for each pot - I should be well on my way to a flat curve ?  Have I missed anything else ? I think with this project it's a very easy build but all the work is in refining it
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on January 06, 2014, 08:56:37 AM
How does the plot for the left channel look?
bumpy road. As previously said, center frequencies between these bandwidth limited gain stages have to be exactly two octaves apart, IE 10,40,160,640Hz and this being a different subject from gain setting. FI your '640 Hz' band looks too high frequency, resulting in a dip below and a peak above this frequency band. With schematic parts values this will result in too low 626.6Hz. Using higher tolerance resistor parts (IE 1K2 instead of 1K27 from schematic) will result in too high 663.1Hz on paper. For the wanted 640Hz and assumed perfect corresponding caps, resistor values needed are 1K243 for R14 and 124R3 for R12 for this band.
Tweaking the series resistor will not fix this behaviour.

Thank you Harpo, I managed to fix the troublesome 40hz-ish dip, looks like there was a dry joint on one of legs of a cap on the 40hz band, not sure but I reheated all joints in this section and the fault is gone.

So I ordered precision value resistors (0.1%) tolerance, inline with the values in the schematic - so I take it that once I replace all higher tolerance resistors currently fitted, and then change series resistors inline with the center point measurements for each pot - I should be well on my way to a flat curve ?  Have I missed anything else ? I think with this project it's a very easy build but all the work is in refining it
in the values needed ? Just run your numbers for the correct values needed when assuming other parts perfect (schematic values are for higher tolerance parts, IE 1K27 would better be 1K241 for your E192 0.1% resistor). This circuit is highly tolerance sensible, so not an easy build.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 09, 2014, 10:14:54 AM
How does the plot for the left channel look?
bumpy road. As previously said, center frequencies between these bandwidth limited gain stages have to be exactly two octaves apart, IE 10,40,160,640Hz and this being a different subject from gain setting. FI your '640 Hz' band looks too high frequency, resulting in a dip below and a peak above this frequency band. With schematic parts values this will result in too low 626.6Hz. Using higher tolerance resistor parts (IE 1K2 instead of 1K27 from schematic) will result in too high 663.1Hz on paper. For the wanted 640Hz and assumed perfect corresponding caps, resistor values needed are 1K243 for R14 and 124R3 for R12 for this band.
Tweaking the series resistor will not fix this behaviour.

Thank you Harpo, I managed to fix the troublesome 40hz-ish dip, looks like there was a dry joint on one of legs of a cap on the 40hz band, not sure but I reheated all joints in this section and the fault is gone.

So I ordered precision value resistors (0.1%) tolerance, inline with the values in the schematic - so I take it that once I replace all higher tolerance resistors currently fitted, and then change series resistors inline with the center point measurements for each pot - I should be well on my way to a flat curve ?  Have I missed anything else ? I think with this project it's a very easy build but all the work is in refining it
in the values needed ? Just run your numbers for the correct values needed when assuming other parts perfect (schematic values are for higher tolerance parts, IE 1K27 would better be 1K241 for your E192 0.1% resistor). This circuit is highly tolerance sensible, so not an easy build.

Hi Harpo,

I've followed all up on all your suggestions and have replaced all of low tolerance resistors with high tolerance values with precision values as per schematic - I.e. Replace 1k5 > 1k54, 1k2 > 1k27 etch. The whole board is now populated with precise resistor values.

I have changed all 5k6 resistors on each frequency band inline with the values generated using  your spreadsheet. I put multiple resistors in series to achieve the values generated in your spreadsheet as most required values were not standard resistor values. I was very particular in this process to ensure that values matched the spreadsheet exactly.

Unfortunately after hours completing this, I still can't get the curve to behave. It's a a little flatter nut still not right... Is there something I am missing ?

If I used alpha rotary switches instead of the pots could this alleviate my problem? I'm really surprised that there haven't been more builders mentioning this issue.

Thanks a lot
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: shot on January 09, 2014, 04:44:50 PM
I had similar issue with very irregular curve, but mine was built using pots from AML.
I found out that those pots were so off that I had to use very different values of series and summing resistors. I had a calculated that value for some resistors had to be around 14k instead of 5k6 to be correct!
It's all explained in Harpo's excel document how to calculate needed values for those resistors.

What I did is I replaced all problematic resistors with combo of resistor+trimmer so I was able to finetune my unit to be almost flat. Almost flat, since when measuring with Smaart software I was able to zoom in so that I can still see that it's off by 0.2db at max. (I won't mention how ugly now my unit looks with all those trimmers above pcb, hehe!)

I still do have problem with my unit that it cannot cut more than 4db, and boosts by +16db. But I'm fine with that. It's mystery but it'll stay as is...

You should measure your switches. If you used high tolerance resistors, your switch is probably behaving a bit off the specified value. This eq is very picky on resistor values! Measure your switches in center position and insert those values into Harpo's excel spreadsheet. You'll probably have an idea what to do next then.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 09, 2014, 05:00:32 PM
I had similar issue with very irregular curve, but mine was built using pots from AML.
I found out that those pots were so off that I had to use very different values of series and summing resistors. I had a calculated that value for some resistors had to be around 14k instead of 5k6 to be correct!
It's all explained in Harpo's excel document how to calculate needed values for those resistors.

What I did is I replaced all problematic resistors with combo of resistor+trimmer so I was able to finetune my unit to be almost flat. Almost flat, since when measuring with Smaart software I was able to zoom in so that I can still see that it's off by 0.2db at max. (I won't mention how ugly now my unit looks with all those trimmers above pcb, hehe!)

I still do have problem with my unit that it cannot cut more than 4db, and boosts by +16db. But I'm fine with that. It's mystery but it'll stay as is...

You should measure your switches. If you used high tolerance resistors, your switch is probably behaving a bit off the specified value. This eq is very picky on resistor values! Measure your switches in center position and insert those values into Harpo's excel spreadsheet. You'll probably have an idea what to do next then.

Hi Shot,

Thanks a lot for your reply. Just to clarify I used pots from AML as well. I used Harpos spreadsheet to calculate the series resistors for each band. Given the measurements of my pots I ended up at with series resistors ranging from 6-12k roughly. Even with these fitted, the EQ is still not flat. I also replaced all high tolerance resistors throughout the board with low tolerance precision resistors.

I was thinking to myself last night that it makes the most sense to introduce a trimmer into the 5k6 position of each band. How did you go about doing that ? Like for example of you needed say 12k470 , would you wire a 10k + 470r + 2k trimmer in series ?

I built this eq in no time at all but I've spent about 10 x longer trying to refine the frequency response... I really wanted to get it right as I can tell this is a good sounding eq so it would be a shame not to have it right.

I was thinking about removing all the pots and wiring up rotary switches but that would be a lot of work so hopefully I can introduce trimmers to fine tune... You don't happen to have any pics of how you wired in your trimmers, I'd be interested to see how you arranged it all

Thanks for your help
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 09, 2014, 05:12:07 PM
Just a second thought ... Why couldn't you just replace the series resistor on each band with say a 15k trim pot and use that solely for adjustment rather than adding other resistors in series??
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: shot on January 09, 2014, 09:45:58 PM
I actually replaced a lot of resistors for resistor+trimmer combo!
All of the series resistors, summing resistor R30, bypass resistor R48 (and R24 not relevant for this issue - I was hunting my boost/cut asymetry issue).

I went for single turn 5K trimmers just cause I had a lot of them around.  Surely 2K would suit even better but hey - I was in a rush to do it same day. For summing and bypass I went with single 100K trimmer.

If you want to use trimmer only (like 15K or such) than be sure to use multi-turn trims. Even with my 5K single turns it was a bit pain to get an exact value.

I soldered resistor (or two) to the legs of the trimmer using center wiper and one outer leg - basic rheostat configuration. Than I'd adjust trimmer so that the series value (resistor+trimmer) is exactly as calculated by spreadsheet. And only then I would solder this combo in place of the resistor. Looks messy but it works. After all is in place, I would trim more precisely passing pink noise and matching it on the transfer function analysis in Smaart software.
I went to replace R48 (bypass) since I was fiddling with R24 and I messed up gain in bypass state. Probably you won't have to do it (but it can't hurt - do it if you feel need to reach absolute unity gain in bypass).

Here's a photo of my unit. It's hard to capture third perspective with camera but I hope it can be informative enough.
Note that some trimmers that have legs too close to other wires have shrinkwrap on their legs. Under the shrinkwrap there's a resistor!
And don't forget to clip the third unused leg of the trimmer just so it doesn't move to a contact with components underside!

(http://s12.postimg.org/vttfhb2f1/EQ3_Dtrimmers.jpg) (http://postimage.org/)
imagen (http://postimage.org/)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on January 09, 2014, 09:58:47 PM
in the values needed ? Just run your numbers for the correct values needed when assuming other parts perfect (schematic values are for higher tolerance parts, IE 1K27 would better be 1K241 for your E192 0.1% resistor). This circuit is highly tolerance sensible, so not an easy build.

Hi Harpo,

I've followed all up on all your suggestions and have replaced all of low tolerance resistors with high tolerance values with precision values as per schematic - I.e. Replace 1k5 > 1k54, 1k2 > 1k27 etch. The whole board is now populated with precise resistor values.
I have changed all 5k6 resistors on each frequency band inline with the values generated using  your spreadsheet. I put multiple resistors in series to achieve the values generated in your spreadsheet as most required values were not standard resistor values. I was very particular in this process to ensure that values matched the spreadsheet exactly.

Unfortunately after hours completing this, I still can't get the curve to behave. It's a a little flatter nut still not right... Is there something I am missing ?
Didn't say so. I said 'run your numbers for the correct values needed', done by [-3dB cutoff freqency=1/(2*PI()*R*C)] with R in ohm and C in Farad.
In each bandwidthlimited gain stage you have a 1st.order HPF, set by the value of the paralleled caps in series with the shunt arm resistor. When you assume the caps value -more unlikely- being perfect 1.00uF||1.00uF=2.00uF=0.000002F, the resistor values for the 10,40,160 and 640Hz bands needed are 7958, 1989, 497.4 and 124.3 ohm. Just for examples sake, if all caps values are maybe 1% high, IE 2.02uF instead of 2.00uF, resistor values would need to change accordingly to 7879, 1970, 492.4 and 123.1 ohm. If all caps values are maybe 1% low, IE 1.98uF instead of 2.00uF, resistor values would need to change accordingly to 8038, 2010, 502.4 and 125.6 ohm. The so called '2K5' shelfing band is a 1280Hz HPF for real with a different from other bands voltage gain setting, so shunt arm resistor value needed is 62.17 ohm with a perfect 2.00uF cap.
IE measure the real world caps value of each band and calculate the resistor value needed by Rx=1/(2*PI*frequency*measured capacitance in F) as being the lesser evil to tweaking caps. Using a multiturn trimmer of sufficient value instead of the shunt arm resistor might be an easier workaround if you don't have the needed value at hand.
Same goes for the LPF at the same -3dB cutoff frequency as the HPF, using same formula, set by the two paralleled 100nF caps=0.2uF in parallel to the gain stages feedback resistor, giving ideal value 79.58K, 19.89K, 4.974K and 1.243K if the caps values are spot on. IE measure the real world 0.2uF caps value and calculate the resistor value needed. Again, a multiturn trimmer (in parallel to a higher value fixed feedback resistor to prevent an open loop gain stage from a failing trimmer) might help. As a followup, any ratio change of Rfb/Rshunt will result in a needed tweaking of the from schematic 5.62K series resistor in order to correct the change in voltage gain of the corresponding band stage.
(all this hassle could have been a walk in the park with derived filters that by definition just have this wanted -6dB/oct slope ...)

Quote
If I used alpha rotary switches instead of the pots could this alleviate my problem?
You have to get the frequencies correct first. Tweaking a bands gain value and/or an off-center level pot by a series resistor is an easy further step (FI by using a multiturn trimmer of sufficient value to substitute the 5.62Ks from schematic).
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 12, 2014, 09:19:45 AM
Thanks Shot + Harpo for your insight, its greatly appreciated. I've taken all of this information on board in tweaking my build further...I'm starting to get my head around the intracacies of this design, its seemed to be deceptively simple... (at first...)

I have replaced the 5k62 series resistors at each band with a 20k multi-turn trimmer. I set the initial value for each trimmer to the series value as calculated in Harpo's spreadsheet. I then fitted the trimmers onboard. I also replaced R30 with a 56k resistor + 20k trimmer, as I knew that R30 would have to be tweaked > 56k due to my R pot center values.

My aim has been to tweak each trimmer with the intention of flatening the frequency curve (all pots set to 0db center) as tested in RMAA. Adjustments have been made gradually on each band.

My freq response at 0db center is still not flat but it's better...I suppose I am aware that the approach i'm taking is very much trial and error as I still don't have my head around the design completely. If the curve indicates a band is > 0db then the resistance is increased on the trimmer, if its < 0db, resistance is decreased.

The worst is a peak on the 650hz band about +0.3db which looks to be a side effect of a cut occuring an octave lower. I've got my 650hz trimmer at its lowest resistance positon so I can't offset the peak any further...

Some questions...:

Shot > thanks for your photo, it certainly helped.
- In your photo - I can see that you fitted a trimmer to the hi-shelf 5k6 resistor position, as I understand it, there shouldn't be any tweaking required on this band, as its additive only, so the 0db at center is of no concern. Any reason why you fitted a trimmer? I have a bump around 7k but it is present in my sweeps during bypass so I am assuming this is normal...

Harpo > thanks for the detailed breakdown... still trying to compute it all. Just a question in regards to the R fb/R30 value... whats the implication of resistance being set too high or too low here? If the value is too low, it would limit the max level setting across all the bands? What if its too high?
Given that I have replaced R30 with a 56k + 20k trimmer, I won't be able to tell if its set to max(R pot. center) * 1.1 ... (As per your formula) without getting the trimmer out of the circuit ...how precise does this value need to be?

My current frequency plot is attached, I am starting to think this is as good as its going to get...

Sorry for the long winded reply and I am reinventing the wheel here, I looked through this thread many times, but this area of the build is very murky, so I am hoping that I can share what I learn with future builders ...
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: shot on January 12, 2014, 09:27:33 AM

- In your photo - I can see that you fitted a trimmer to the hi-shelf 5k6 resistor position, as I understand it, there shouldn't be any tweaking required on this band, as its additive only, so the 0db at center is of no concern. Any reason why you fitted a trimmer?

I was aware that it shouldn't be of any concern, but when I was about to unscrew and desolder, I thought "what the hell". Since I had enough I just went on it also. Just to be sure I won't have to do it all again in case this value also needs to be tweaked. :)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: [email protected] on January 12, 2014, 10:58:03 AM
This is great information for me as I'm just starting the process of getting the correct value resistors..
Found this project to be challenging in a good way and learnt more than some of the more 'painting by numbers' type projects.. Anyway, thanks for sharing guys!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 12, 2014, 11:27:16 AM

- In your photo - I can see that you fitted a trimmer to the hi-shelf 5k6 resistor position, as I understand it, there shouldn't be any tweaking required on this band, as its additive only, so the 0db at center is of no concern. Any reason why you fitted a trimmer?

I was aware that it shouldn't be of any concern, but when I was about to unscrew and desolder, I thought "what the hell". Since I had enough I just went on it also. Just to be sure I won't have to do it all again in case this value also needs to be tweaked. :)

Hi Shot, thanks for the info. Did you end up having to trim on the hi shelf pot ? Did you approach the trimmer adjustments in a similar was to me ? I.e. Adjust in whatever way makes freq response flatter at 0db center. My concern is that I don't know what value R30 ends up being, how does your freq response compare to mine ? All my boosts and cuts are working properly at least
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on January 12, 2014, 12:44:46 PM
Harpo > thanks for the detailed breakdown... still trying to compute it all. Just a question in regards to the R fb/R30 value... whats the implication of resistance being set too high or too low here? If the value is too low, it would limit the max level setting across all the bands? What if its too high?
Given that I have replaced R30 with a 56k + 20k trimmer, I won't be able to tell if its set to max(R pot. center) * 1.1 ... (As per your formula) without getting the trimmer out of the circuit ...how precise does this value need to be?
Value is not critical, only adjusting overall unity gain level (IE 0dB in/0dB out with level pots centered and air-band off). I'd not put a trimmer in series to R30, but YMMV. If the trimmer fails one day -most often only the wiper looses contact but I've seen them fail at the outer ends as well- this summing amp stage is running open loop, only limited by rail voltages. I'd probably increase R30 to maybe 120K and put a 200K trimmer in parallel with trimmers initial value about centered for a much wider + and - trim possibility and if this trimmer should fail, this would only be a +6.6dB boost in level instead of a show stopper.
Tweaking parts values, you seem to be starting at the wrong side. As repeatedly said, you won't get a flat response out, no matter how much you tweak the level pot center values/summing amp gain settings, as long as you don't have the center frequencies of the different bands in the correct spot. FI you could plot the responses of the 10,40,160,640Hz bands when measuring at the NE5532 pin 1 and pin 7 of IC2 and IC3. Some DAW software would give you exact numbers at what frequency each max.level is located, just to know where these center frequencies of your build are located exactly if you don't want to measure caps values and calculate the corresponding resistor values needed to get there. Maybe reread my last post.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 12, 2014, 08:05:27 PM
Harpo > thanks for the detailed breakdown... still trying to compute it all. Just a question in regards to the R fb/R30 value... whats the implication of resistance being set too high or too low here? If the value is too low, it would limit the max level setting across all the bands? What if its too high?
Given that I have replaced R30 with a 56k + 20k trimmer, I won't be able to tell if its set to max(R pot. center) * 1.1 ... (As per your formula) without getting the trimmer out of the circuit ...how precise does this value need to be?
Value is not critical, only adjusting overall unity gain level (IE 0dB in/0dB out with level pots centered and air-band off). I'd not put a trimmer in series to R30, but YMMV. If the trimmer fails one day -most often only the wiper looses contact but I've seen them fail at the outer ends as well- this summing amp stage is running open loop, only limited by rail voltages. I'd probably increase R30 to maybe 120K and put a 200K trimmer in parallel with trimmers initial value about centered for a much wider + and - trim possibility and if this trimmer should fail, this would only be a +6.6dB boost in level instead of a show stopper.
Tweaking parts values, you seem to be starting at the wrong side. As repeatedly said, you won't get a flat response out, no matter how much you tweak the level pot center values/summing amp gain settings, as long as you don't have the center frequencies of the different bands in the correct spot. FI you could plot the responses of the 10,40,160,640Hz bands when measuring at the NE5532 pin 1 and pin 7 of IC2 and IC3. Some DAW software would give you exact numbers at what frequency each max.level is located, just to know where these center frequencies of your build are located exactly if you don't want to measure caps values and calculate the corresponding resistor values needed to get there. Maybe reread my last post.

Thanks Harpo, I just re-read your previous posts on this subject - I think the penny finally dropped for me. Looking over this thread for many hours - What I am wondering is why there aren't more builders on this thread who have mentioned these issues. There are a few references to the issues but not in any great detail. In my mind, these 'problems' seem to be unavoidable as a consequence of the design... ?

I need to rework much of the board to encompass your suggestions. Looking over your previous posts in more detail, I am hoping I've finally got the gist of whats required.

This is my plan of attack:

1. Desolder paralled 2uf/0.2uf cap combos from each filter section

2. Measure 'real world' capacitance of paralled caps:
SUB-C55,C11 (2uf) & C12,C19 (0.2uf)
40hz-C54,C9 (2uf) & C10,C18 (0.2uf)
160Hz-C53,C7 (2uf) & C17,C8 (0.2uf)
650hz-C52,C5 (2uf) & C16,C6 (0.2uf)
2.5k-C51,C6 (2uf)

3. Calculate required resistor values using formula - Rx=1/(2*PI*frequency*measured capacitance in F)
Based upon actual measurements of paralled caps
SUB-R19,R21
40hz-R18,R20
60hz-R15,R17
650hz-R12,R14
2.5k-R9,R11

4. Solder fixed value resistor+trimmer combo to achieve calculated resistor values. Using DMM, measure each resistor+trimmer combo and preset to calculated values.
> Solder resistor combo to PCB @ required positions.

5. Adjust 5k62 series resistor(s) - (R44, R42, R40, R38, R36) based on 470k rev log pot center values (use Harpo's spreadsheet)
> Use 20k multiturn trimmers, using DMM preset each value to calculated values using Harpo's spreadsheet
> Fit trimmers in R44, R42, R40, R38, R36 positions

I know your recommendation was to fit resistor+trimmer(s) in parallel to prevent catastrophe if failed trimmer is incurred, but my thoughts were to replace the trimmers once the the correct values have been achieved.

Have I possibly missed anything?

Thanks for your on-going help, I'm hoping my learning can assist other builders in future. I have spent so much time building this EQ so I am keen to get it 100%.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 13, 2014, 03:00:36 AM
This is great information for me as I'm just starting the process of getting the correct value resistors..
Found this project to be challenging in a good way and learnt more than some of the more 'painting by numbers' type projects.. Anyway, thanks for sharing guys!

Hi DeathToneM,
Glad to see someone else still interested in this project... much credit to Harpo, the genius behind helping me refine my build!

What has become clear to me is that this a very easy build, from a 'component installation' perspective - there are no esoteric components or any difficult wiring/soldering....

However - the part that I completely over looked was how much work it would take to get the frequency behavior right... Having built many many other popular and apparently more complex projects, I have yet to incur one as fiddly and as time consuming as this....
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: [email protected] on January 13, 2014, 04:34:42 AM
Quote
However - the part that I completely over looked was how much work it would take to get the frequency behavior right... Having built many many other popular and apparently more complex projects, I have yet to incur one as fiddly and as time consuming as this...

Yep, my thoughts exactly.. But it's much easier to work out after reading yours and Harpo's explanations! And will be for new builders to come.. So thanks to all involved for documenting that..
 I personally think this EQ is worth getting right as it sounds great!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 13, 2014, 05:05:00 AM
Quote
However - the part that I completely over looked was how much work it would take to get the frequency behavior right... Having built many many other popular and apparently more complex projects, I have yet to incur one as fiddly and as time consuming as this...

Yep, my thoughts exactly.. But it's much easier to work out after reading yours and Harpo's explanations! And will be for new builders to come.. So thanks to all involved for documenting that..
 I personally think this EQ is worth getting right as it sounds great!

Completely agree... I wish I knew what I know now before having built this EQ... I have soldered and de-soldered components that many times ... Few busted PCB traces down the track...
With foresight, now knowing how particular this design is with component values... I'd measure my 2uf/0.2uf parallel caps and tailor the resistors accordingly as per Harpo's formula. Hopefully Harpo concurs that my plan of attack is a correct interpretation of what is required here... You will have he benefit of all of this knowledge upfront so hopefully you won't have to dissect your build like I have... I also wish of gone with stepped switches but my front panel design doesn't have the space for that many rotary switches... Fun and games
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on January 13, 2014, 06:05:59 AM
This is my plan of attack:

1. Desolder paralled 2uf/0.2uf cap combos from each filter section
Why ?
Just pull IC2 and IC3 and lift one side of the frequency/gain setting resistors that would be lifted anyway to adjust to the required value, IE R21 where it connects to C11||C55 and either side of R23 for the sub band as an example.

Quote
5. Adjust 5k62 series resistor(s) - (R44, R42, R40, R38, R36) based on 470k rev log pot center values (use Harpo's spreadsheet)
> Use 20k multiturn trimmers, using DMM preset each value to calculated values using Harpo's spreadsheet
> Fit trimmers in R44, R42, R40, R38, R36 positions
substituting the 5K62 series resistors (ment for 500k rev.log pots with 10% value at 50% rotation) with -depending on value needed- 10K or 20K trimmers, trimmers pretrimmed to the calculated value and fitted in R45, R43, R41, R39, R37 positions would give you some spare 5k62 resistors and a cleaner layout. YMMV.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 13, 2014, 08:09:27 AM
This is my plan of attack:

1. Desolder paralled 2uf/0.2uf cap combos from each filter section
Why ?
Just pull IC2 and IC3 and lift one side of the frequency/gain setting resistors that would be lifted anyway to adjust to the required value, IE R21 where it connects to C11||C55 and either side of R23 for the sub band as an example.

Quote
5. Adjust 5k62 series resistor(s) - (R44, R42, R40, R38, R36) based on 470k rev log pot center values (use Harpo's spreadsheet)
> Use 20k multiturn trimmers, using DMM preset each value to calculated values using Harpo's spreadsheet
> Fit trimmers in R44, R42, R40, R38, R36 positions
substituting the 5K62 series resistors (ment for 500k rev.log pots with 10% value at 50% rotation) with -depending on value needed- 10K or 20K trimmers, trimmers pretrimmed to the calculated value and fitted in R45, R43, R41, R39, R37 positions would give you some spare 5k62 resistors and a cleaner layout. YMMV.

Harpo, thanks! Invaluable info and insight... Off to the local electronics supply store tomorrow to pickup some more trimmers, I'll report back on my progress... I'm hopeful that our exchanges on this subject will serve future builders well... I'm excited to hopefully finish this off finally
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 15, 2014, 10:55:15 PM
This is my plan of attack:

1. Desolder paralled 2uf/0.2uf cap combos from each filter section
Why ?
Just pull IC2 and IC3 and lift one side of the frequency/gain setting resistors that would be lifted anyway to adjust to the required value, IE R21 where it connects to C11||C55 and either side of R23 for the sub band as an example.

Quote
5. Adjust 5k62 series resistor(s) - (R44, R42, R40, R38, R36) based on 470k rev log pot center values (use Harpo's spreadsheet)
> Use 20k multiturn trimmers, using DMM preset each value to calculated values using Harpo's spreadsheet
> Fit trimmers in R44, R42, R40, R38, R36 positions
substituting the 5K62 series resistors (ment for 500k rev.log pots with 10% value at 50% rotation) with -depending on value needed- 10K or 20K trimmers, trimmers pretrimmed to the calculated value and fitted in R45, R43, R41, R39, R37 positions would give you some spare 5k62 resistors and a cleaner layout. YMMV.

Hey Harpo,

I've spent the last few days reworking my left channel as per all the discussed recommendations, I had to use a lot of multiturn trimmers due to the 'non standard' resistor values required. 

I have calculated resistor values against real-world values for 2uf & 0.2uf paralleled caps. 5k6 series resistor values were also calculated and set with trimmers based upon your spreadsheet.

All trimmers were pretrimmed and checked with a DMM before fitting to the circuit.

These are my calculations:

Calculated resistor values adjusted for paralled caps (2uf/0.2uf):

10 -   C55+C11   = 2.1   - R21 -   Calculated Resistor Value = 7.58
10 -    C12+C19   = 0.201   - R23 -    Calculated Resistor Value = 79.18
40 -    C54+C9   = 1.991   - R18 -   Calculated Resistor Value = 2.00
40 -    C18+C10   = 0.201   - R20 -   Calculated Resistor Value = 19.80
160 -    C53+C7   = 1.975   - R15 -   Calculated Resistor Value = 503.66R
160 -    C17+C8   = 0.203   - R17 -   Calculated Resistor Value = 4.90
640 -    C52+C5   = 1.979   - R12 -   Calculated Resistor Value = 125.66R
640 -    C16+C16   = 0.201   - R14 -   Calculated Resistor Value = 1.24
1280 -   C51+C3   = 1.973   - R9 -   Calculated Resistor Value = 63.02R


470k rev Log pot,  center indent adjusted values:

Sub   - R44   - 445,000 - 56,800 - R45 = 10,300
40 Hz   - R42   - 472,000 - 54,600 - R43 = 12,500
160 Hz   - R40   - 483,000 - 55,600 - R41 = 11,500
640 Hz   - R38   - 451,000 - 54,400 - R39 = 12,700
2.56 kHz - R36   - 481,000 - 61,000 - R37 = 6,100

R fb = 67,100

Attached is the new frequency plot. Still not flat, but the curve looks 'healthy'... Do you think adjusting the series resistors will get me closer, or more component tweaking? I've been meticulous about making sure every trimmer was set to the correct value.

The only thing I didn't touch in this whole process was the air band, is any tweaking required here? As you can see this is a bit of a boost up high

Any thoughts about where to go from here? This has been quite a learning process. The circuit board is starting to look a bit like a charred mess from soldering and desoldering so many times!  I'm really determined to get this right....
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on January 16, 2014, 08:30:18 AM
Attached is the new frequency plot. Still not flat, but the curve looks 'healthy'... Do you think adjusting the series resistors will get me closer,..
Yepp (wild guessing better than +/-0.1dB). Reason is, tweaking for correct center frequencies also changed the gain setting ratio of the feedback und shunt resistors.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 16, 2014, 08:40:03 AM
Attached is the new frequency plot. Still not flat, but the curve looks 'healthy'... Do you think adjusting the series resistors will get me closer,..
Yepp (wild guessing better than +/-0.1dB). Reason is, tweaking for correct center frequencies also changed the gain setting ratio of the feedback und shunt resistors.

I think I follow you... I'm thinking some subtle adjusting of the  series resistor trimmers will get me where I want to be. Only thought is the +0.5 boost between ~5-10k looks a bit ominous ? Should I pay any attention to r35 on the high shelf band ?  I've left it at 5k62 as I figured that with the rotary switch in the off position it shouldn't be introducing a boost in this region when off ? This has been a good learning curve... Thanks again
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 19, 2014, 08:45:14 AM
Hey Harpo,

Sorry to keep spamming this thread...

Spent some more time tweaking this EQ, I am not too sure if I completely understood when you said "tweaking for correct center frequencies also changed the gain setting ratio of the feedback und shunt resistors."

I'm still trying to correct the curve but since I don't fully understand this area I feel like i'm aimlessly adjusting trimmers, this is how the curve looks at the moment...

My frequencies must be slightly off (not exactly an octave apart, so high 40hz results in dip at 80hz etc) 

Is there a methodogical way you can suggest to further correct the frequencies? What has become very apparent with this design is that everything needs to be exact... as you know I already set the frequency resistor values precisely with the trimmers

Hope other builders can learn from this on going discussion...

Thanks
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 21, 2014, 08:08:13 AM
This post post may fall into the void as I'm not sure if there are too many people still interested in this build. It's safe to say that I've become a little obsessed about getting this build 100%...

I just finished reading over every page of this thread... I can now see that many other builders have had issues with getting a flat response with pots centered. After days/months trying to achieve this, it might be time to move on..

After some more deliberation - What I'd like to know is, is there a significant impact running the rails at -/+ 16v rather than 18?

Reason I asked is that I can't get anymore than +6db boost on any band, I am running my rails a little low at 16v, could this be starving the circuit and impacting on max boost ? I know that r30 value could limit the total amount of gain possible across all bands but +6db boost max seems very low
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on January 21, 2014, 06:02:38 PM
Reason I asked is that I can't get anymore than +6db boost on any band, I am running my rails a little low at 16v, could this be starving the circuit and impacting on max boost ? I know that r30 value could limit the total amount of gain possible across all bands but +6db boost max seems very low
Nothing to do with +/-16V or +/-18V. For +6dB max.boost your R30 parts value must have decreased or series resistors increased a lot. Usual boost is about +14.3dB with 5K62 series resistors and 56K2 Rfb. What is the amount of your RMS input voltage ? You might have the 'normalize the amplitude of test signals before analysis' checked in RMAA and a dBFS to dBV translation is converter specific, so might be opamps signals operating close to their supply boundaries.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 21, 2014, 06:18:09 PM
Reason I asked is that I can't get anymore than +6db boost on any band, I am running my rails a little low at 16v, could this be starving the circuit and impacting on max boost ? I know that r30 value could limit the total amount of gain possible across all bands but +6db boost max seems very low
Nothing to do with +/-16V or +/-18V. For +6dB max.boost your R30 parts value must have decreased or series resistors increased a lot. Usual boost is about +14.3dB with 5K62 series resistors and 56K2 Rfb. What is the amount of your RMS input voltage ? You might have the 'normalize the amplitude of test signals before analysis' checked in RMAA and a dBFS to dBV translation is converter specific, so might be opamps signals operating close to their supply boundaries.

Thanks Harpo, i'm not in the studio now to test.. but I think you're right, I checked in RMAA and the 'normalize...' checkbox is ticked by default on a fresh install.

Rfb is set to 67,100.
R Series values are set as follows = SUB: 10,300; 40hz: 13,100; 160hz: 11,500; 640hz: 12,700; 2.5k: 6,100
Each of these values + pot center value result in a gain value of exactly 1 so the pot center calibration should be spot on.

So to address your point, R30 has actually increased and the series values aren't excessively high.

Whilst I have you, in your previous post you mentioned that tweaking the center frequencies also changed the gain setting ratio of the feedback and shunt resistors - whats the best way to systematically address that? Or maybe its best to leave it with some -/+ 0.2db fluctuation. Looking over this entire thread from start to finish again last night, it looks like this issue has plagued many users and maybe ear is the best tool here ?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 31, 2014, 07:10:16 AM
The battle with this eq continues...
After fitting 14 trimmers to my left channel, many measurements and tweaks... My left channel is almost flat at pots centered, certainly as good as it will get.

I just completed the same surgery on my right channel.
Unfortunately after all these mods, I have run into an issue on the right channel. I have a very very low output, doesn't even register on my meters... With headphones on and the volume cranked I can hear a faint signal passing, you can hear changes in the audio as pots are adjusted, so I know it's working in principal

Could I have introduced a short somewhere that could result in this behavior ? All voltages are good throughout circuit, I can't seem to track down the fault. I suspected something had gone a miss around the feedback resistor but no such luck. Same output in bypass and out

Any help greatly appreciated, I can't rest until this project is complete
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on January 31, 2014, 08:31:40 AM
You already excluded a broken right side XLR input or output connection ?
With input signal present, compare right side with left side channel to see where signal get lost might be the easiest approach, following from input to output, IE compare AC voltages at U4-pin1,...., U5-pin6, U4-pin7.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on January 31, 2014, 08:49:05 AM
You already excluded a broken right side XLR input or output connection ?
With input signal present, compare right side with left side channel to see where signal get lost might be the easiest approach, following from input to output, IE compare AC voltages at U4-pin1,...., U5-pin6, U4-pin7.

Yeah checked the XLR wiring, those molex crimp pins have sent me on a wild goose chase before. I'll follow your lead and see where I get. It's strange as you can hear the eq working even though it's barely audible. I'm cross eyed from putting all these trimmers in, we will see what the new day brings. Thanks again
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Autophase on February 02, 2014, 10:40:49 AM
Unfortunately I don't have the time to finish my Nite EQ, if anyone is after a pair of stereo boards I've got a post in the Black Market
http://groupdiy.com/index.php?topic=55086.0 (http://groupdiy.com/index.php?topic=55086.0)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on February 03, 2014, 01:08:06 AM
You already excluded a broken right side XLR input or output connection ?
With input signal present, compare right side with left side channel to see where signal get lost might be the easiest approach, following from input to output, IE compare AC voltages at U4-pin1,...., U5-pin6, U4-pin7.

Hi Harpo,

I've followed your recommendation, with a 1khz sine WAVE. I found a few deviations between the working and non working channels.

U5 - Pin 6 on working channel measures 0.868VAC. On the non working channel I have a negligible AC reading here.

Pin 7 on U6 is showing 0VAC on the non working channel.
On working channel this measures at +1.732VAC for the given input signal, which is the same reading when measuring at the output XLR pins.

Bear in mind this channel use to work fine, the issue has only arisen in the process of swapping out a heap of resistors with trimmers (R21,R23,R18,R20,R15,R17,R12,R14,R9 & R45,R43,R41,R39,R37).

I've already removed all of the IC's and checked that the trimmers are at their correct calculated resistance and they all checked out OK

No doubt I have introduced a fault during this process as the left channel is working fine with the same configuration. I am just having trouble finding where...

Thanks a lot
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on February 03, 2014, 05:17:09 AM
U5 - Pin 6 on working channel measures 0.868VAC. On the non working channel I have a negligible AC reading here.
So either the opamp is broken or signal doesn't arrive at its non-inverting input (this is a virtual ground node, so current not voltage).
L/R voltages are the same at U4-pin1 (output of input debalancing stage) ?
L/R voltages are the same at U2-pin1 (output of 640Hz gain stage) ?
Does last measurement voltage or slightly lower arrive at the non working channel U5-pin2 with the U5 opamp out of its socket (broken trace check) ?

Quote
Pin 7 on U6 is showing 0VAC on the non working channel.
On working channel this measures at +1.732VAC for the given input signal, which is the same reading when measuring at the output XLR pins.
U4-pin7 on working channel (unsigned)1.732VAC with jumper set for unbalanced out config. On non working channel this is only a followup from U5-pin6 (inverting 2* nothing is still nothing).
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on February 05, 2014, 06:20:27 AM
Quote from: Bonsaimaster
Ok here is what I got. As I plug the module in my rack the power LED lights up and the Peak LED lights up. No signal passes thru. When I hook it up with my Classic API extension card non of the LED's light up. Voltage checks are all over with U1 and U4 showing varying voltages. TP4 TP5 show about .1mV.Any thoughts?

Thanks in advance
Bonsaimaster
Took me a while to figure out what project your PM might be related to.
Did you place the 4 jumpers at the J9 connector, IE 'Link 1&3, 2&4, 7&9, 8&10 for Rear panel I/O', as explained at the left side of 'Prodigy Nite500 EQ schematic.pdf', so your input signal across XLR-pins2/3 arrives at TP4/TP5 ?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on February 10, 2014, 09:56:23 PM
Hi Harpo, and anyone else still interested in this thread...

So this is how I finished up with my unit. (I did find a dry joint on my right channel which was causing a loss of signal).

With 14 trimmers fitted on each channel to compensate for parts tolerances, my frequency response is better, but I think its as close as its going to get.

So far, i'd say that EQ sounds "good", not excellent but I am thinking this is due to some dips in low end frequencies. Attached is how my frequency response ended up.

I feel that the signal through the EQ (all pots centered) kind of sounds like its loosing a bit of 'balls' (subjective term... maybe = loss of some low end??

Drum sample: No EQ - https://dl.dropboxusercontent.com/u/108741277/niteeq/drumloop-noEQ.mp3
Drum sample: Nite EQ (all pots centered) - https://dl.dropboxusercontent.com/u/108741277/niteeq/drumloop-niteEQ.mp3

It becomes a bit of an interesting exercise - am I percieving some low end loss because I can see it on a graph, or can actually hear it? I *think* my -0.35db~ dip @ 350hz-ish is this perceived loss of low end (or "balls")

There is a pretty small volume drop with the EQ engaged due to tweaks of feedback resistor...

The EQ sounds pretty nice if you disregard any empirical info/precision and just crank the knobs until it sounds good, more like an effect in a way, and probably the way this was designed to be used...

Interested to hear any thoughts?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dmnieto on February 10, 2014, 11:08:09 PM
Hi Harpo, and anyone else still interested in this thread...

So this is how I finished up with my unit. (I did find a dry joint on my right channel which was causing a loss of signal).

With 14 trimmers fitted on each channel to compensate for parts tolerances, my frequency response is better, but I think its as close as its going to get.

So far, i'd say that EQ sounds "good", not excellent but I am thinking this is due to some dips in low end frequencies. Attached is how my frequency response ended up.

I feel that the signal through the EQ (all pots centered) kind of sounds like its loosing a bit of 'balls' (subjective term... maybe = loss of some low end??

Drum sample: No EQ - https://dl.dropboxusercontent.com/u/108741277/niteeq/drumloop-noEQ.mp3
Drum sample: Nite EQ (all pots centered) - https://dl.dropboxusercontent.com/u/108741277/niteeq/drumloop-niteEQ.mp3

It becomes a bit of an interesting exercise - am I percieving some low end loss because I can see it on a graph, or can actually hear it? I *think* my -0.35db~ dip @ 350hz-ish is this perceived loss of low end (or "balls")

There is a pretty small volume drop with the EQ engaged due to tweaks of feedback resistor...

The EQ sounds pretty nice if you disregard any empirical info/precision and just crank the knobs until it sounds good, more like an effect in a way, and probably the way this was designed to be used...

Interested to hear any thoughts?

No, i can hear it too, but it might be more related with the fact that the tracks are massively in anti-phase... Just mono it and you will see.

In any case, hearing it only one channel at a time, it does not seem like it has lost punch for me... It is a tad brighter though.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on February 10, 2014, 11:48:13 PM
Hi Harpo, and anyone else still interested in this thread...

So this is how I finished up with my unit. (I did find a dry joint on my right channel which was causing a loss of signal).

With 14 trimmers fitted on each channel to compensate for parts tolerances, my frequency response is better, but I think its as close as its going to get.

So far, i'd say that EQ sounds "good", not excellent but I am thinking this is due to some dips in low end frequencies. Attached is how my frequency response ended up.

I feel that the signal through the EQ (all pots centered) kind of sounds like its loosing a bit of 'balls' (subjective term... maybe = loss of some low end??

Drum sample: No EQ - https://dl.dropboxusercontent.com/u/108741277/niteeq/drumloop-noEQ.mp3
Drum sample: Nite EQ (all pots centered) - https://dl.dropboxusercontent.com/u/108741277/niteeq/drumloop-niteEQ.mp3

It becomes a bit of an interesting exercise - am I percieving some low end loss because I can see it on a graph, or can actually hear it? I *think* my -0.35db~ dip @ 350hz-ish is this perceived loss of low end (or "balls")

There is a pretty small volume drop with the EQ engaged due to tweaks of feedback resistor...

The EQ sounds pretty nice if you disregard any empirical info/precision and just crank the knobs until it sounds good, more like an effect in a way, and probably the way this was designed to be used...

Interested to hear any thoughts?

No, i can hear it too, but it might be more related with the fact that the tracks are massively in anti-phase... Just mono it and you will see.

In any case, hearing it only one channel at a time, it does not seem like it has lost punch for me... It is a tad brighter though.

Hey there, thanks for the feedback... I didn't check that actually. When you say anti phase ... You mean the eq-d track L and R channels are out of phase with each other ? I wonder what could cause that... Xlr wiring pins reversed ?
I'll have another listen... The slight brightness/boost +0.5db~ in the highs could be attributed by the wide high end freq boost
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on February 10, 2014, 11:52:11 PM
EDIT: Looking at the waveforms I can see exactly what you mean, completely out of phase...
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dmnieto on February 11, 2014, 12:39:20 AM
Hey there, thanks for the feedback... I didn't check that actually. When you say anti phase ... You mean the eq-d track L and R channels are out of phase with each other ? I wonder what could cause that... Xlr wiring pins reversed ?
I'll have another listen... The slight brightness/boost +0.5db~ in the highs could be attributed by the wide high end freq boost

I'd say that you have the hot an cold pins in one of the channels reversed, or some kind of wiring issue. It was quite fenomenal on a first listen because it felt like the sound was bouncing from one side to another in my room when i moved the head a little bit.

But yeah, I did feel a slight less punch and detail in the sound, it could be because the original was a bit louder and that somehow the mp3 compression added more artifacts. It is also that the 350Hz is right in the middle of where the fundamentals of the kit/snare are so the 0.5dB difference can actually be heard. Dunno.

Do you mind printing the wav files and inverting the phase of one of the channels?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on February 11, 2014, 02:14:36 AM
Hey there, thanks for the feedback... I didn't check that actually. When you say anti phase ... You mean the eq-d track L and R channels are out of phase with each other ? I wonder what could cause that... Xlr wiring pins reversed ?
I'll have another listen... The slight brightness/boost +0.5db~ in the highs could be attributed by the wide high end freq boost

I'd say that you have the hot an cold pins in one of the channels reversed, or some kind of wiring issue. It was quite fenomenal on a first listen because it felt like the sound was bouncing from one side to another in my room when i moved the head a little bit.

But yeah, I did feel a slight less punch and detail in the sound, it could be because the original was a bit louder and that somehow the mp3 compression added more artifacts. It is also that the 350Hz is right in the middle of where the fundamentals of the kit/snare are so the 0.5dB difference can actually be heard. Dunno.

Do you mind printing the wav files and inverting the phase of one of the channels?

Hey dmnieto,

You're a legend ! I can now see I have reversed the hot and cold pins on the left channel XLR in. What an idiot I am!!! Because these boards are self etched , there's no silk screen so I stupidly wired the input wrong on this channel! I'm pretty certain it will work properly now. The dip at 350hz is only about -0.3, it's wide as well so I don't think it should be too catastrophic...
But having the polarity totally flipped on one channel is diabolical!
I really was scratching my head wondering why it sounded so "odd", interestingly as you tweak some of the knobs, it kind of started to sound better (phase shift due to boosting certain bands..?)
Anyhow I'll report back soon once I've fixed it. Such a simple oversight that I embarrassingly have probably spent hours working on - I'm glad I posted the sound clips and that you took the time to listen to them. Thanks again...
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dmnieto on February 11, 2014, 02:53:07 AM

You're a legend ! I can now see I have reversed the hot and cold pins on the left channel XLR in. What an idiot I am!!!

You are not an idiot, I made the same mistake on one of my 1176. I chased that one for a full weekend. In my case it manifested as oscillation at low levels... This was due because I was measuring on a single ended equipment and reversing the phase was actually creating a positive feedback instability when I was using the passive attenuator so the signal was very close to ground.

On the other hand, it was a cool LFO.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on February 11, 2014, 04:20:18 AM

You're a legend ! I can now see I have reversed the hot and cold pins on the left channel XLR in. What an idiot I am!!!

You are not an idiot, I made the same mistake on one of my 1176. I chased that one for a full weekend. In my case it manifested as oscillation at low levels... This was due because I was measuring on a single ended equipment and reversing the phase was actually creating a positive feedback instability when I was using the passive attenuator so the signal was very close to ground.

On the other hand, it was a cool LFO.

This is perfect .... All fixed! Such a minor oversight with major implications. The sound was so strange before, it makes perfect sense now ... And more importantly it sounds awesome, the way I thought it always should have sounded.
I'm glad you found your bug on your 1176 build. I loved building my 1176s , the last one worked perfectly on first power up... As opposed to this build, I would hate to see how many hours I spent tweaking this unit and chasing this bizarre issue. I'll be happy never taking the lid off this thing again
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Jordan on August 15, 2014, 05:42:25 AM
Salut,
Je découvre cet EQ aujourd'hui. Peut être un peu tard ... Est il possible d'acheter les PCB? Merci pour votre aide !
Amicalement. ;)

Jordan
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: steves.mastering on October 28, 2014, 11:40:55 AM
Hi,

Is anyone still making these PCBs? or does anyone have the etch files so i can make myself some? :)

thank you very much

Ste
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: snaper on March 04, 2015, 03:25:31 AM
Hi,

Is anyone still making these PCBs? or does anyone have the etch files so i can make myself some? :)

thank you very much

Ste
Interested in etch layout too :D
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on March 04, 2015, 06:36:15 AM
Hi,

Is anyone still making these PCBs? or does anyone have the etch files so i can make myself some? :)

thank you very much

Ste

Schematic:

https://dl.dropboxusercontent.com/u/12176165/Night%20EQ%20Docs/Nite_3D_EQ.JPG

BOM:

https://dl.dropboxusercontent.com/u/12176165/Night%20EQ%20Docs/NIGHT_EQ_Parts.doc

https://dl.dropboxusercontent.com/u/12176165/Night%20EQ%20Docs/Nite_EQ_Parts_-_fIXED.xls
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on March 05, 2015, 01:37:04 AM
Hi Whoops

PM sent regarding these files.

Peter
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on March 05, 2015, 02:18:06 PM
Hi Whoops

PM sent regarding these files.

Peter

Links removed

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: mrscary on March 18, 2015, 12:17:47 PM
Does anybody still have PCBs available for this, or perhaps the etching files so I can make my own?

Thanks
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: troubleous on June 19, 2015, 02:48:06 AM
Hi fellow builders and diyer's!

I'm building a stereo unit here and I have a peculiar problem:

One channel is working as expected and sounds very good and is dead silent.

The second channel works all the way up to "air" frequencies:  I can hear only a very slight boost in selected air frequencies, even if I boost the air gain full on. With the working channel the air boos works as expected. When I flip the rotary switch through the air frequencies, I can hear them changing correctly, but the boost is just way too low.

I built the channels identical, measuring all the resistors and now I wen't through the resistors once more and all seem correct (*knocking on wood*). I also checked wiring many times but can't find anything. Also tried replacing the 500K pot for air gain, but the effect (or lack of it) still remains.

Anyone has a clue what could be the culprit/ problem here?

Thanks a lot in advance!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: weiss on June 20, 2015, 09:30:46 PM
Hi,
I would like to do a version of the night EQ where instead of having separate controls for the channels, I would only have one control for each band, controlling both left and right channels at the same time.

I was thinking about Dual Gang 470K Rev Log Pots, audiomaintenance has them.
http://www.audiomaintenance.com/acatalog/om-01-055_extended_info.html

Even if the "Air" control and "Vari" switchhad to be independent, it would be great to have only one control for the "Sub" , "40hz", "100hz", "650hz" and "2,5K"

Do you think it's possible ?

didn't find any answer to this post, so i am asking again ;-)

did anyone manage to control two boards with one set of dual gang potentiometers? i want to have matched channels and save some space on my front panel :)
would these pots work? http://www.audiomaintenance.com/acatalog/om-01-055_extended_info.html

do i have to install separate controls for each channel for the air band, air gain and bypass control?

thanks
weiss
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Script on June 20, 2015, 10:05:44 PM
Hey Weiss,

I haven't finished my unit yet (it's been sitting on the bench/shelf for quite a while now). Yet I remember someone suggesting 50K pots instead of 500K ones (requires recalculating and swapping some resistors on the board), cos 50K pots are more readily available/cheaper.

Matching pots is critical for this unit to get flat response in mid position. Theoretically what you aim for is possible, but requires tedious pot matching (10-20% deviance between gangs). Two ideas to counter mismatches that should make life much easier:

(1) use stepped controls (either dual mono [2U] or stereo [1U]) -- elegant solution
(2) stay dual mono with well-matched pots and process material in MS mode -- more versatile solution

I have made up my mind a long time ago. When I go back to the unit it will be option 2.

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: weiss on June 21, 2015, 06:20:06 AM
I haven't finished my unit yet (it's been sitting on the bench/shelf for quite a while now). Yet I remember someone suggesting 50K pots instead of 500K ones (requires recalculating and swapping some resistors on the board), cos 50K pots are more readily available/cheaper.

Matching pots is critical for this unit to get flat response in mid position. Theoretically what you aim for is possible, but requires tedious pot matching (10-20% deviance between gangs). Two ideas to counter mismatches that should make life much easier:

(1) use stepped controls (either dual mono [2U] or stereo [1U]) -- elegant solution
(2) stay dual mono with well-matched pots and process material in MS mode -- more versatile solution

I have made up my mind a long time ago. When I go back to the unit it will be option 2.


Thanks for your reply! I ask because i already have the potentiometers here and don't want to buy new ones. So controlling both pcb's with a single set of pots would work?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Script on June 21, 2015, 10:10:43 AM
I see. Then why not go for it. Should be easy enough to wire everything (even if wiring "sucks" ;)

Either way, I'd also measure the dual gang pots. Do the two gangs give you roughly the same resistance readings?
(1) Measure between pins 1 and 3. If values of both gangs are identical/close = good.
(2) Measure between pins 1 and 2 (with wiper/pot set to mid position). If values are identical/close = good.

If values are not close at all, hmm... wire it all up anyway and listen.

There is a mathematically ideal resistance reading at mid-position (btw. pins 1 and 2) of 1/10th of total pot resistance. With a dual-gang pot this is highly critical cos any deviation between gangs will result in volume differences between L and R channels.

Found an excel "calculator" file on my harddrive (originally by Harpo -- hope it's okay to post) that might be useful, though untested by me. Download and delete the ".pdf" to open it as an excel file.

Viel Glueck
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Script on June 21, 2015, 02:22:25 PM
Read back in the thread. Now I know why the boards have been in a box on a shelf for such a long time. This unit needs meticulous resistor calculation (not just pot series resistor for mid-centering the pots; first it needs tweaking the frequency resistors, and then the gain) to get a flat response when engaged with pots set to zero.

@Harpo (and everybody else)
After getting the frequencies right, would getting the gain right not be better done by tweaking the 1K opamp input resistors (R10, 13, 16, 19, 22) rather than tweaking the pot series trimmers (orig. "5K62" per schematic)?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: weiss on June 21, 2015, 06:40:58 PM
Read back in the thread. Now I know why the boards have been in a box on a shelf for such a long time. This unit needs meticulous resistor calculation (not just pot series resistor for mid-centering the pots; first it needs tweaking the frequency resistors, and then the gain) to get a flat response when engaged with pots set to zero.

@Harpo (and everybody else)
After getting the frequencies right, would getting the gain right not be better done by tweaking the 1K opamp input resistors (R10, 13, 16, 19, 22) rather than tweaking the pot series trimmers (orig. "5K62" per schematic)?

i don't get this. why is the unit not working properly when using the right values for the resistors?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Script on June 21, 2015, 06:47:15 PM
Quote
i don't get this. why is the unit not working properly when using the right values for the resistors?

Read all posts by Harpo in this thread about getting the frequencies right.
Shouldn't stop you from soldering in the 500K's.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: weiss on June 21, 2015, 06:48:53 PM
Thanks man. I will do ;) So i use the dual gang pots, but what about the frequency selection of the air band. is it possible to use one switch for L and R?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on June 22, 2015, 04:58:25 PM
After getting the frequencies right, would getting the gain right not be better done by tweaking the 1K opamp input resistors (R10, 13, 16, 19, 22) rather than tweaking the pot series trimmers (orig. "5K62" per schematic)?
No. Tweaking/increasing the resistor in front of the non-inverting gain stages wouldn't change a thing (except increased resistive noise). You'd still need to adjust the series resistors at the rheostats because of the -for usual- +/-20% pot tolerances.
For a single knob per frequency band stereo build you'd need a lot of rev.log pots (read hundreds, with a little luck every 20th pot might be just close enough to be acceptable) for a resistance at center, total resistance and taper matching.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Script on June 22, 2015, 11:24:12 PM
@Harpo, thanks a lot for clarifying yet again. It's highly appreciated.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Script on June 23, 2015, 05:09:25 AM
Let's see whether I got this right.

The cap values are also critical to get the HP and LP filter stage right (and with it the filter stage gain). Because with less-than-ideal filter cap values (and resistor values), these inconspicuous pot series resistors suddenly fulfill a triple function: (1) to set the gain for the summing opamp, (2) to set the pot's centre position, and (3) to compensate for messed-up filter stage gain. This makes any compromise here more or less messy, even impossible -- at least on paper. Right?

Why? Because less-than-ideal cap values mess up the filter bands. This could be adjusted by altering the filter resistors. However, doing that messes up the opamp gain. The then less-than-ideal opamp gain could be compensated for by adjusting the pot series resistor. However, this messes not only with the centre position of the pot (which takes some effort to set right by adjusting this very same pot series resistor), it also messes with the band's gain into the summing opamp determined also by this very same pot series resistor. Good luck with that!

Said differently, in order to not mess things up down the chain, the real-world filter cap values need to be trimmed to be as spot-on as possible in the first place. Solving less-than-ideal capacitance of, for example, 0.9uf+1.0uf=1.9uf requires adding 0.1uf in parallel (on the underside of the board) to get the required 2.0uf. Only then can we insert the exact(!) resistor values (Harpo's excel sheet) required for the HP/LP filter bands without messing up the filter stage gains. Once we get all this right we still have to compromise in the 'pot section' (weakest link in the chain) by either dropping the pot's zero position or accepting sacrifices in single band gain.


IDEAS
(1) Put trimmer in front of pot to make total resistance of pot 'look' like 500K or allow for pot-related adjustments? Eh? Not sure whether this adds to solving the 'how to set the "zero" position' problem at all without messing up gain again.
(2) Ideally there should be an extra gain stage in each band after the pots(?) exclusively for trimming gain offsets of up to 1db or so, but there isn't. Maybe in the next revision.
(3) I don't like the idea of adding 14 or more trimmers to a unit. I'd rather tag resistors in parallel.
(4) Here's what I'd do: Get the filter bands spot-on first and then insert the calculated pot series resistor. Then dial in 'zero' on non-indented pot on the front plate until frequency response is at 0db on scope and put a knob on it with its 'visual' marker pointing to 12 o'clock.
(5) In use, take the pots and all other flat-frequency issues (like pot bending law and max volume attenuation) out of the L/R matching equation by running stereo material through two units in MS mode only. Then dial in desired sound without even looking at the face plate and A/B via hard bypass.

Hm, I still feel that there's something missing in my thinking (especially in Idea 1). Not sure though what.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: e.oelberg on June 23, 2015, 02:43:47 PM
50k will give you way less noise, 500k is noisy
(http://www.beis.de/Elektronik/Nomograms/R-Noise/R-Noise-20kHz_700.GIF)
so 10dB less noise
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: weiss on June 23, 2015, 04:35:31 PM
-100dB? Still not bad for my purpose
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: e.oelberg on June 23, 2015, 05:01:11 PM
94
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: e.oelberg on June 23, 2015, 05:02:37 PM
look for earlier posts of mine, I don't remember what I did, but it was very simple and it does have an audible effect when pushing signals
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on June 23, 2015, 06:50:31 PM
94
Resistive/Johnson noise of the 500K resistor is -97.8dB. (@weiss: only by use of this single resistor value and per resistor. This -97.8dB is not the noise figure of the complete circuit...)
A 50K introduces -107.8dB, a 10K introduces -114.8dB of resistive noise.
Johnson noise in dB = LOG(SQRT(4* 1.38E-23 * 300 * 500,000 * 19,980))*20
with Boltzmann constant 1.38E-23 Joules/Kelvin, assumed room/box temperature 300 Kelvin, 500,000 your tested resistor value in ohm and bandwidth 19,980Hz for your 20Hz...20kHz audible range of interest.
With highest gain setting, this 500K variable resistor/pot/rheostat is dialed in for zero ohm (=lowest resistive noise), further leading to the conclusion that the parts value of the series resistor in front and corresponding feedback resistor as well might be responsible for these unnessesary high numbers ...
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on June 03, 2016, 04:50:24 AM
Hi all

I have some PCBs available for this project, please check this WM thread if you are interested.

Gren Mic Pre
S800 EQ
Green PSU
5003 EQ
Nite EQ

Regards
Peter
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: fazeka on June 07, 2016, 02:42:00 AM
With Peter making PCBs again, anyone going to have front panels?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on June 07, 2016, 08:59:08 AM
With Peter making PCBs again, anyone going to have front panels?

You should talK with Dan, a lot of people bought this PCB's so I guess there would be some interest in cases or front panels.
If theres enough interest he might do a run:

http://groupdiy.com/index.php?topic=35422.0

 
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: pstcho on September 18, 2016, 04:07:11 AM
Hello there, are there any PCB left?   :o

thanks
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: smokinpcb on October 13, 2016, 06:03:37 PM
does anyone know what kind of pots are used in the new maag units?
the indents are super awesome
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on October 16, 2016, 09:37:52 PM
does anyone know what kind of pots are used in the new maag units?
the indents are super awesome

that would be nice to know actually,
also the resistance at the center needs tight tolerances, so probably they have the pots custom made for them 
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on October 17, 2016, 09:17:23 AM
does anyone know what kind of pots are used in the new maag units?
the indents are super awesome
Without knowing the context of the corresponding circuit behind (they might know better by now how to build it with a lot less hassle), this question is either irrelevant or at best of academical use. As always YMMV.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: smokinpcb on October 20, 2016, 12:39:36 PM
I was more referring to brand over resistance value etc.
I have some friends that have the 500 series eq4's, if they are cool with me taking a look inside the units I'll post what I find!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dirty1_1garry on October 22, 2016, 12:23:28 PM
Hi folks!

I became interested on Night EQ. And before building it I've decide to emulate it.
For easier schematic understanding I've simplifying it (original schemaric was found it at the beginning of the thread) and made it more readable.
Here is what I've got:
(http://groupdiy.com/gallery/0/47634-221016121211.png)

For LTspice emulating I've emulate only one band - 40Hz. And here is what I've got:
(http://groupdiy.com/gallery/0/47634-221016121343.png)
As you can see, changing resistance of gain pot change only whole frequency range gain, not only one band. So what I'm doing wrong?)

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on October 22, 2016, 02:04:40 PM
I think the way it works is all pots resistance affect all the frequencies, I think you can't change one pot resistance alone without compensating all the other pots resistance also.

Have you seen the excel document to calculate the change in resistors?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: peterc on October 22, 2016, 03:58:02 PM
Remember as well, that these bands have VERY wide bandwidth.

So this might be the reason

Peter
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dirty1_1garry on October 23, 2016, 11:19:55 AM
I think the way it works is all pots resistance affect all the frequencies, I think you can't change one pot resistance alone without compensating all the other pots resistance also.

Hmmm, will try!

Have you seen the excel document to calculate the change in resistors?

At what page I can find excel doc?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on October 23, 2016, 12:27:51 PM
Hi folks!

I became interested on Night EQ. And before building it I've decide to emulate it.
For easier schematic understanding I've simplifying it (original schemaric was found it at the beginning of the thread) and made it more readable.
Here is what I've got:
//snip

For LTspice emulating I've emulate only one band - 40Hz. And here is what I've got:
//snip
As you can see, changing resistance of gain pot change only whole frequency range gain, not only one band. So what I'm doing wrong?)
Looking at your dB numbers, your emulation schematic is missing the shunt arm resistor R24 from the voltage attenuator R25/R24.
As you can see, this "EQ" consists of a number of bandwidth limited non-inverting gain stages (not filters). Other than inverting gain stages or filters, these gain stages with 1st.order -6dB/oct. slopes stop falling when unity gain is archieved. You need all stages built exactly two octaves apart, so these summed up stages reconstruct the whole audible frequency band. The frequency and gain setting parts values shown in the schematic are only rough approximation numbers. What you perceive as cut is lesser boost and the max.archievable cut is set by prementioned attenuator.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dirty1_1garry on October 23, 2016, 02:29:34 PM
Looking at your dB numbers, your emulation schematic is missing the shunt arm resistor R24 from the voltage attenuator R25/R24.
As you can see, this "EQ" consists of a number of bandwidth limited non-inverting gain stages (not filters). Other than inverting gain stages or filters, these gain stages with 1st.order -6dB/oct. slopes stop falling when unity gain is archieved. You need all stages built exactly two octaves apart, so these summed up stages reconstruct the whole audible frequency band. The frequency and gain setting parts values shown in the schematic are only rough approximation numbers. What you perceive as cut is lesser boost and the max.archievable cut is set by prementioned attenuator.
Thanks for tips!
Here is what I've got with adding all stages. Emulation curves start to look more real :)
SUB band curve with 250K 100K 70K 50K 40K 30K 20K 15K gain resistor, all other are 40K (close to flat position).
When gain res = 500K or 250K curve changes just a little bit. When gain res = 1R (max gain) sub bell rise up to +14dB but with +6dB on all other range. So range from 250K to 15K looks more useful for me.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dirty1_1garry on October 23, 2016, 02:47:54 PM
Any experience with rev log pot? What relation of pot turn angle with resistive of rev log pot?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on October 23, 2016, 11:20:36 PM
Hmmm, will try!

At what page I can find excel doc?

page 41 of this thread,
check my post
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dirty1_1garry on October 24, 2016, 03:59:22 PM
page 41 of this thread,
check my post

Yeah, got it, thanks! Found a lot of interesting info here. For example, that was really interesting to see your eq curves. Mine pretty close to yours)
Absolutely not a universal eq, but of course that's no matter if it do the right job)
Here is what I've got again:
(https://img-fotki.yandex.ru/get/173476/6870362.0/0_145531_dd9e681a_XXL.png) (https://fotki.yandex.ru/next/users/igorbuben/album/333576/view/1332529)

(https://img-fotki.yandex.ru/get/104700/6870362.0/0_145532_e28ada07_L.png) (https://fotki.yandex.ru/next/users/igorbuben/album/333576/view/1332530)


But I've found one confusion fact - when I boost only one freq up to 5dB, all freq range boost at about 1-1.5dB, so total boost of one freq above all range  became  around 4dB. But when I boost two freq, for example 40 and 2500 here is what I've got:
(https://img-fotki.yandex.ru/get/102077/6870362.0/0_145533_c4c8f4a0_L.png) (https://fotki.yandex.ru/next/users/igorbuben/album/333576/view/1332531)

So it looks like gain compensation  pot would be pretty useful here.


Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dirty1_1garry on October 25, 2016, 09:28:40 AM
Haha, found a video that shown a curves of EQ4 plug-in. It gives the same bump(from 3 to 6dB) on all freq range when you boost only one band. That gives a small confirmation to my emulations :)

https://www.youtube.com/watch?v=lFS1bhaM-SM
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: febo2609 on January 01, 2017, 11:14:08 AM
Does anybody  have PCB etching files so I can make my own?  PDF/gerber?

Thanks
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on January 05, 2017, 01:26:38 AM
There's a lot of unused pcb's around members,
post in the black market asking to buy some
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: MarcOliver on April 18, 2017, 08:08:56 AM
Hello Peeps!

Im fairly new on this forum, my name is Marc Oliver, a UK based engineer.

I am looking to purchase two Nite EQ3D boards, any chance someone has a pair out the back? otherwise i will have to have them made to order, which will cost me an arm and a leg.


Thank you

Marc
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on April 27, 2017, 08:55:02 PM
Hello Peeps!

Im fairly new on this forum, my name is Marc Oliver, a UK based engineer.

I am looking to purchase two Nite EQ3D boards, any chance someone has a pair out the back? otherwise i will have to have them made to order, which will cost me an arm and a leg.


Thank you

Marc

Hi Marc,
search in the Black Market section ,
and also Post a "WTB" there. There are a lot of these pcb's in drawers
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: fazeka on May 10, 2017, 04:43:41 AM
Hey all,

I have a dead original Nightpro unit from the late 90s. I suspect it has corroded traces, some bad enough to cause a channel not to work. I think it's bad enough to where stopping the corrosion is too late... so thinking about having these PCBs cloned, wondering if anyone could help? I would like to have these cloned to use with the original pots and switches (and their positions, that line up with the front panel) of the original. Also, the footprint of the power supply and the interconnect between the two boards would mean it would be a simple drop in replacement into original cases. And I get to use the original switched mode power supply...

But I may be just dreaming at this point...  :o

If anyone can assist with this, please PM me. Thanks.

Otherwise, Peter, if you are reading this, do you happen to have an extra pair of PCBs lying around?  ???
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on May 10, 2017, 10:31:02 AM
Hey all,

I have a dead original Nightpro unit from the late 90s. I suspect it has corroded traces, some bad enough to cause a channel not to work. I think it's bad enough to where stopping the corrosion is too late... so thinking about having these PCBs cloned, wondering if anyone could help? I would like to have these cloned to use with the original pots and switches (and their positions, that line up with the front panel) of the original. Also, the footprint of the power supply and the interconnect between the two boards would mean it would be a simple drop in replacement into original cases. And I get to use the original switched mode power supply...

But I may be just dreaming at this point...  :o

If anyone can assist with this, please PM me. Thanks.

Otherwise, Peter, if you are reading this, do you happen to have an extra pair of PCBs lying around?  ???

Post pictures of your unit, and the bad traces.
It can and should be fixed.
No new need for new pcb's

Bad traces can be redone, corroded traces should be cleaned with Iso Alchool and them brushed and then thin them with solder.

After the fix, you should clean everything, all the tracves and then use some PCB varnish to seal the traces and prevent them from corroding in the future.


As your question about cloning, that has been done already, it's the reason why this thread exists.

If you don't want your unit, I have some 3D "AIR" EQ - "Night EQ"  pcb's , we can make a deal to exchange your unit for a cloned one.

Best regards
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on May 10, 2017, 06:12:15 PM
2. I acquired this unit because it was original and because I suspected a simpler more straightforward fix at the component level. Moreover, if I wanted to build a clone, I would have by now and not bothered with this original.

Well you were asking for a clone. That's what's you u wrote
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Le Roux on May 21, 2017, 06:26:13 PM
Just putting my eq together but the green psu is acting up.
I've confirmed all components.
I built 3 of these and all acting similar
23.67V
-14.74V
7.37V

.93V
-10V
9.71V

23.7V
-14.77V
7.31V

Thanks to anyone who has suggestions
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on May 22, 2017, 06:45:34 AM
I built 3 of these and all acting similar

So you did the same mistake in the 3 PSU's you built.

You have to fidure out what you migh have done wrong
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Le Roux on May 22, 2017, 01:09:58 PM
I noticed a low output from the bridge rectifier on the positive rail.
Although the datasheet is similar to the recommended BR64, I installed the BR310.  Should work?

I also noticed the schematic on the twin-x site differs from the overlay which is the actual circuit.
The circuit seems to have two additional 1N4007 highlighted in yellow.

Should these be excluded?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: shot on May 22, 2017, 04:13:37 PM
But why do you want to use +48v on your PSU?
This EQ doesn't need it, unless you want to combine this EQ with some other preamp into a single case.

I would first try and take out all the components related to +48v, and then see what is going on with the rest of the supply.
Possible causes of malfunction could be wrong wiring on the AC input (maybe you've switched ground and one AC supply??)... then maybe wrong orientation of the bridge rectifier, some other diode or elecrolytic cap?
Inspect that.
In most cases it's something stupid.
Happens to all of us  ???

:)

Luka
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Le Roux on May 22, 2017, 07:17:00 PM
Using one of the three power supplies for an access 312 preamp, therefore required the 48V

I stripped all components out of the 48V section, and it dropped the negative rail from -14.97V to  -11.41V and brought the positive rail from 7.53V to 11.41V.
Pulled every component until there was nothing left. Finally had +15V and -15V on the rectifier.

Every resistor was checked 10x as I spend the entire day at this, plus many hours last night.

The only thing that I question is the use of wima caps for the 100nF instead of electrolytics, (Which the overlay doesn't have a + or - marker, but the bom states electrolytics) the BR310 instead of the BR64 and the voltage regulators were KA317TU instead of LM317T.

I don't believe any of those things matter; as I've been over the data sheets.

I'm at a loss, and probably just going to use a JLM now.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on May 22, 2017, 08:04:54 PM
Using one of the three power supplies for an access 312 preamp, therefore required the 48V

I stripped all components out of the 48V section, and it dropped the negative rail from -14.97V to  -11.41V and brought the positive rail from 7.53V to 11.41V.
Pulled every component until there was nothing left. Finally had +15V and -15V on the rectifier.

Every resistor was checked 10x as I spend the entire day at this, plus many hours last night.

The only thing that I question is the use of wima caps for the 100nF instead of electrolytics, (Which the overlay doesn't have a + or - marker, but the bom states electrolytics) the BR310 instead of the BR64 and the voltage regulators were KA317TU instead of LM317T.

I don't believe any of those things matter; as I've been over the data sheets.

I'm at a loss, and probably just going to use a JLM now.

Wait... Chill Out.. Let's take one step at a time

BR310 instead of the BR64

I don't know what it is the 310 or 64, you need a Bridge Rectifier rated 1 Amp or more, does your fit the Bill?
If so, move on

The only thing that I question is the use of wima caps for the 100nF instead of electrolytics,


That doesnt make a diference, move on


KA317TU instead of LM317T.


Same thing, move on

The circuit seems to have two additional 1N4007 highlighted in yellow.


Those are protection Diodes, leave them and move on





Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on May 22, 2017, 08:14:18 PM
Troubleshooting of the PSU:

- What transformer are you using, whats the secondaries voltages?

- Did you properly connected the transformer secondaries to the PSU?

- Do you have the Bridge Rectifier properly installed?

- What AC voltage do you have at the BR input?

- What DC voltage do you have at the BR output?

- Measure and post the voltages you have at each regulator input and output

- take pictures of the setup, pcbs and transformer and connections

If you are feeding the 317 regulators input with +15V you wont be able to regulate the output to +15V,
you need at least 1.2V more at the input than at the ouput. In reality just to be safe I would have at least 17V minimum at the input if I wanted to regulate the output to 15V

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: fazeka on May 27, 2017, 09:39:51 PM
Yup. You're right.  :) And I guess I overreacted earlier... it wasn't really bad at all!

There were only a few traces that needed a touch-up. Then as you say I cleaned the boards with iso alcohol and did a recap as a few caps were open and all is well again. Great sounding EQ! I can see why these are in demand!

Thanks,
Chris

Post pictures of your unit, and the bad traces.
It can and should be fixed.
No new need for new pcb's

Bad traces can be redone, corroded traces should be cleaned with Iso Alchool and them brushed and then thin them with solder.

After the fix, you should clean everything, all the tracves and then use some PCB varnish to seal the traces and prevent them from corroding in the future.

As your question about cloning, that has been done already, it's the reason why this thread exists.

If you don't want your unit, I have some 3D "AIR" EQ - "Night EQ"  pcb's , we can make a deal to exchange your unit for a cloned one.

Best regards
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: febo2609 on June 09, 2017, 04:25:21 PM
Does anybody  have PCB etching files so I can make my own?  PDF/gerber?

Thanks
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dlmorley on July 04, 2017, 02:40:05 PM
Is this project still live? Are PCB's available?
Thx!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on July 05, 2017, 07:05:11 PM
Is this project still live? Are PCB's available?
Thx!

It is your first post, so you should read the forum rules first:

6. Use the search function (thoroughly) before posting.  It is quite possible your question may have already been answered by knowledgeable members that have been generous with their time.  A tremendous wealth of knowledge is actively updated and compiled in the "Meta" threads--take advantage of them.

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: choolder on August 11, 2017, 04:15:23 AM
Hi guys, I'm wiring up the lorlin switch and I'm not sure how to do it. Already did a search but I didn't find anything.

B 2 3 4 5 6 is pretty obvious
A also but where do I connect the 2-6 on the pcb?

Kind regards,

Peter
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on August 11, 2017, 04:45:04 AM
A also but where do I connect the 2-6 on the pcb?
"a" and "2-6" are 5mm apart, located close between the 2500Hz and HI-SHELF level pots.
"2-6" is a piece of shorting wire, soldered to the pins 2,3,4,5 and 6 of the "a" section of the lorlin type switch with the other end of the wire connecting to this "2-6" spot on pcb.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: choolder on August 11, 2017, 04:06:40 PM
thanks! works perfect!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: loji on August 17, 2017, 04:39:07 PM
So I have an ORIGINAL of this unit on the way ... the big 2u, blackface unit ...1/4dB stepped dual concentric switches , linear power supply, transformer balanced outputs.. . I am excited to scope it out.

I also have the original manual for the Eq3 (not 3d) if anyone wants to see it.

Specs from original manual :
input impedance - 20k Ohm
Output impedance - 50 Ohm
Headroom : +25dbm
max phase shift : 30 degrees (one control set max, all others set flat)
musical phase shift : 10 degrees  (controls adjusted for average musical compensation)
+/- 0.5db : 10Hz-125kHz
+/- 3dB : 7Hz & 330Khz
 


I do have a question ... has any one swapped the 5532/5543 opamps in these? Given the way this circuit works, (band split summing) what would be a good fit? Their socketed, so would seem an easy way to experiment with the tone

I'm thinking of modding the air-band on these with a switch to add the select frequencies (like the Eq3d/EQ4). I used to have those schematics from a prior build, but I seem to have lost them ... does anyone have the section for the air-band freq selector? I'm thinking just adding a 6-pole switch to the front of the stock unit would be easy.

I'll update with more info next week ... Those grayhill dual concentric switches cost a pretty penny!! So I'm excited for the 1/4db control this will offer


(also to the poster a few pages back ... the unit is correct with only -4dB cut, and +15dB boost ... that's the way it's built).
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on August 17, 2017, 08:37:42 PM
I have the schematics, I think I also posted them on this thread some pages ago.

Send me a pm,
Would love to have the manual for your unit also.

Regards
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on August 18, 2017, 03:33:57 PM
Check the wiring first, you don't know who might have messed around with the unit before. If it everything works properly and both channels sound the same maybe it's just pin2 and pin3 that are swapped.

I
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: loji on August 25, 2017, 03:46:37 PM
Yup .. input was swapped. working perfectly now.  -- Attached is the filter board + knobs. (Grayhill series 71) pic --

They *really* didn't want people getting into this thing! .. I had to chip out  a bit of concrete or epoxy two screws had been filled with, and also had to slot a stripped bolt with the dremel to get it out.

But inside it's built like  tank!   Big whooping transformers on the outputs, sealed switches, thick traces, IC's had the labels scrapped off and aren't socketed. It's a very nice sound on program ... I'm going to hang onto it for awhile and compare it against my (original) Sontec 430b, and Bettermaker as far as the 'air' shelf goes .... all 3x are known to be excellent.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: druu on September 19, 2017, 08:15:31 PM
I've managed to build up a unit using 50k Lin rotaries and used Harpo's spreadsheet to calculate the values for each position. I've also changed the 56k in the input to 5k6 and added trimmers adjusted to 560R for each band/channel instead of the 5k6 from the original circuit. Centre position on the rotary is 5k6 for 0dB, using 11k3 parallel to reduce the switching noise as calculated on Harpo's spreadsheet. Noise is considerably lower with this setup.

Everything works great, frequencies are accurate enough but I seem to only be getting +/-3dB boost and cut. It seems as though each step is only 0.25dB and not 0.5dB as calculated.

Can anyone advise if there is a resistor value on the mainboard I can alter to get the desired +/-5.5dB?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on September 20, 2017, 04:33:55 AM
I've managed to build up a unit using 50k Lin rotaries
switched resistors substituting a rev.log taper pot, not a lin taper pot.
Quote
I've also changed the 56k in the input to 5k6 and added trimmers adjusted to 560R for each band/channel instead of the 5k6 from the original circuit. Centre position on the rotary is 5k6 for 0dB, using 11k3 parallel to reduce the switching noise as calculated on Harpo's spreadsheet. Noise is considerably lower with this setup.
5K6 probably refering to R30=R48. C13 previously 22pF increased to 220pF as well ? Keeping the C1 parts value, at least get rid of the 10K R5.
Quote
Everything works great, frequencies are accurate enough but I seem to only be getting +/-3dB boost and cut. It seems as though each step is only 0.25dB and not 0.5dB as calculated.
Might be jumper setting for balanced/unbalanced connection not set properly for corresponding following piece of gear with balanced/unbalanced cable in between that causes the missing 6dB. Same loss when switched to bypass ?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: druu on September 20, 2017, 07:01:57 AM
Thanks for the reply Harpo.

Yes, sorry I meant 50k rev log. Values calculated using your v2 spreadsheet. I selected 5.5 max boost and -5.5 max cut but using MBB 23 step rotaries, so require the parallel R, calculated for -6 dB max cut with a value of 11k3 closest E96. This allows for 5k6 centre position value on the rotaries.

R30 has been substituted for 5k6 and R48 not used as I'm using separate relay bypass. Is R48 still required? I've not changed C13 as you mentioned, nor removed 10k R5 but will try this as per your advice. Would this cause the odd boost/cut limitation I'm seeing?

I don't think I have an issue with the bal/unbalanced section. With all band gain controls at centre position, high shelf gain at full CCW and shelf selector OFF, I have a reasonably flat  response and if I feed a -12 signal  from the DAW and back out I still get -12 on the master out with no loss.

In your spreadsheet you mention for the parallel R value, that the dB value must not be higher than regular max.cut. What is the regular max.cut you are referring to? Is it the +/-5.5 values chosen in the section above or the total for the circuit (i.e. 20dB?).

Appreciate your help with this stuff as always..
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: druu on September 21, 2017, 07:36:08 AM
I've replaced the 22pF for a 220pF and also removed the 10k at R5. No difference in the gain max boost/cut unfortunately..
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: druu on September 22, 2017, 07:15:02 AM
So I've realized that I'm using series string rotaries, calculated based on +/-5.5dB with 23 steps. Also using the parallel R which was calculated as being 11k3. With this I have the following:

closest E96 value to match E15
75000
27000
15000
9100
6200
4300
3300
2400
2000
1800
1500
1000
1100
820
750
680
620
430
510
360
430
390
3900

158590 total R but also includes parallel R if 11k3.

If I measure this as a 'pot', it is 10.5k CCW and 2.8k CW with 5k6 centre position. The spreadsheet has these figures:

"required R in
(to substitute Rseries+RV)"
10548
9958
9401
8875
8379
7910
7468
7050
6656
6283
5932
5600
5287
4991
4712
4448
4199
3964
3743
3533
3336
3149
2973

So R30 I'm using 5k6 and also worth mentioning I'm using relay bypass. With R30 at 5k6, series string resistors at 0R and steps calculated per the spreadsheet with parallel R, I get the same signal when bypassed and when IN.

The +/-3dB is still an issue - is this down to the circuit seeing only a 10k 'pot'?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: druu on September 23, 2017, 09:47:56 PM
Just to give an idea of what I'm getting with the bands:

https://imgur.com/a/AAGZs

Just to recap;
- R30 = 5k6
- 23 step rotary switches calculated using Harpo's spreadsheet for +/-5.5dB max boost/cut, including parallel R value of 11k3 (for -6dB max cut between steps)
- Series string trimmers set to full CCW (i.e. 0R)
- Rotary switch values - CCW @ 10.5k, centre position @ 5k6 and CW @ 2k8
- Relay bypassed used but no difference between feeding a -12dB 1kHz tone whether IN or bypassed so centre position on all bands ('air' gain at full CCW) is at correct unity gain.

This is occurring on both channels as per the screenshot. After reading the whole thread it seems a few have experienced this issue but unfortunately no success stories on how it was overcome (e.g. here.. (https://groupdiy.com/index.php?topic=19789.msg696652#msg696652)).

Any ideas?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: frazzman on September 26, 2017, 04:44:52 AM
I too have had similar issues to druu, and the other users who reported similar behaviour.

Has anyone successfully built a unit with stepped rotaries using Harpos logic?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dagoose on September 26, 2017, 05:29:24 AM
Guys.. it's not a standard series attenuator. I think that is where your problems might be.
It's just two resistors in parallel with the one switched into the circuit.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: druu on September 26, 2017, 06:31:04 AM
Guys.. it's not a standard series attenuator. I think that is where your problems might be.
It's just two resistors in parallel with the one switched into the circuit.

Thanks Jeff. Totally get that but my series string rotary steps match the required figures from Harpo’s spreadsheet, all the way from CCW to CW. It’s basicallt the equivalent of the ladder type rotary..
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: druu on September 26, 2017, 07:48:03 PM
hmm.. so that is what i'm missing here.  :-[
They are indeed.. totaly missed that!
Thanks! 8)

EDIT: i shorted r39 and now i get a bit more boost (max 2.5 db) but still no 5db as it should be with 31k6.  ???
When i replace the 31k6 with 10k i get something like 5.5 db boost which is good. If i use the sheet with 10k max in the boost it says it's boosting 15db, which is totally different then the 5.5db i see.
With 330k for cut (= -15db according sheet) i get a cut of something like 3.5/4 db but with the 100k= -5db (according top sheet) i get only about 1db of cut.

anyone? I really don't get it..

Jeff, did you have to tweak more values to overcome this issue?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dagoose on September 27, 2017, 03:16:08 AM
Jeff, did you have to tweak more values to overcome this issue?
To be honest, it was quite some time ago but I think I didn't really tweak a lot of things.
The only thing that came to my mind is that I had an issue with  more boost then cut caused by the 5.62k resistor that had to be bridged. For the rest, these are the values that I used IIRC. This is a copy/paste from a small txt doc I had in my EQ3D map.

step 1 to 2 = 36k5
step 2 to 3 = 28k7
step 3 to 4 = 23k2
step 4 to 5 = 18k2
step 5 to 6 = 14k7
step 6 to 7 = 11k5
step 7 to 8 = 9k09
step 8 to 9 = 7k32
step 9 to 10 = 5k76
step 10 to 11 = 4k64
step 11 to sum = 17k8 (replaces R37,39,41,43,45)

less great than ugly, but its not that hard to do. See the little wiring sketch on the right side. The resistors for each step position at the switches are listed in the green cells, with a resistor in parallel (value in the orange cell) to get it less jumpy between switch positions. Each of these building blocks substitute a 470K rev.log. pot (RV36, RV38, .., RV44) with its 5.62K series resistor (R37, R39, .., R45) for each freq.band gain setting part of the summing amp.

Maybe you want to use a 12 pos. lorlin type switch instead, limited to 11 pos. for a center position at step 6, so you just replace the default value '23' with '11' for 'step positions' in the yellow cell. Maybe you want a different cut/boost range (within limits), so replace the default values '5.5' and '-5.5' with maybe '5' and '-12.487' for 'max.boost' and 'max.cut' in the yellow cells. Each time you update a value in the yellow cells for your needs, the whole chart is recalculated and resistor values picked for the closest E96 value to match your plan.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dagoose on September 27, 2017, 03:22:14 AM
I think this was the sheet that I used for calculations. (rename the jpg to xls)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: druu on September 27, 2017, 08:10:16 AM
Thanks for the reply Jeff.

I'm a little confused as to how you got your values mentioned above but at the same time, you're using a ladder type with less steps so would differ.

I've just tried to simulate with the values I'm using in the circuit (mentioned above a few posts) but also getting spot on values (see attached).. more than confused now.. it must really not like the series string assembly of the rotary, but wondering why this is the case..
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on September 28, 2017, 08:49:18 AM
I've just tried to simulate with the values I'm using in the circuit...
... missing the 1k54 shunt arm resistor between your R2 and R3 (original R24/R25) for the -22dB pad (and ignoring the -6dB balanced line receiver and the last inverting +6dB stage that should keep it at unity with correct jumper settings).
Your tested response for the range 1Hz...1.33Hz doesn't make much sense for the 640Hz band (and missing all remaining bands that add up to this band as well due to the non-inverting gain stages with their -6dB slopes that stop to fall when unity gain is archieved. Max.cut is about -5.5dB with all remaining bands set for +/-0dB.)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: druu on September 28, 2017, 06:34:41 PM
Sorry Harpo, I had the previous sim zoomed to show the gain steps. I've attached another slightly updated but I didn't realize the missing 1k54. In this updated one I added real life resistance steps at each step point on Rgain and also added the 11k3 parallel R to simulate my series string rotary.

Can you advise on what I should be seeing if I measure Vrms at XLR in vs XLR out? I do seem to have a variance there, if I feed 1.0v input, I get around 0.7v output, a gain drop of 3dB?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: druu on September 29, 2017, 05:12:05 AM
OK! I've managed to replicate the issue in the schem based on your suggestions Harpo. I added all bands (except the Air band or selector) and also added the 1k5 arm shunt, which you were spot on about as I had simulated without it and it was clearly showing unity at +22dB on the sim.

Now that I've replicated, is there any way I can try to remedy this and somehow get it back to being +/-5.5dB as calculated in the spreadsheet?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: druu on September 29, 2017, 05:15:06 AM
Spice schematic..

https://imgur.com/a/nQPH5
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on September 29, 2017, 05:15:46 AM
.. but I didn't realize the missing 1k54.
.. that is still missing in your sim schematic. These fixed resistors 18.2K and 1.54K form a -22dB voltage divider (the 1.54K better would be a 1.58K with other parts -more unlikely- being perfect) that substitute a 20K trimmer from design stage.
Quote
In this updated one I added real life resistance steps at each step point on Rgain and also added the 11k3 parallel R to simulate my series string rotary.
.. showing, the 0.5dB steps should work as calculated.
Quote
Can you advise on what I should be seeing if I measure Vrms at XLR in vs XLR out? I do seem to have a variance there, if I feed 1.0v input, I get around 0.7v output, a gain drop of 3dB?
measured at what frequency ? You could do a frequency sweep across the audible band to see the overall outcome with all level settings centered) As already said, your sim is missing the remaining bands that add up to the frequency under test by a more or lesser amount.
Imagine one of the paralleled frequency setting caps missing a connection to the pcb trace will shift the response of this bandwidth limited gain stage up by one octave, causing this 3dB bump (and a 3dB dip 2 octaves below), just one idea of a possible cause.

oops, answering while you posted ..
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: druu on September 29, 2017, 07:34:45 PM
Thanks Harpo. Did you see my latest posts above?

To answer your question on frequency, this was a 1kHz tone sent from my DAW.

Also, the simulation above should show this isn't a pcb related issue.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: druu on September 29, 2017, 09:17:53 PM
Ok so I've just tried without the parallel R 11k3 on the rotary switches and when running the simulation without these on any band, shows a -6dB drop in total frequency response but gain steps are returned to the normal 0.5dB for each step.

So it seems the parallel R is causing a total drop of -6dB in each band as a side effect, effectively halving each bands gain range?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: druu on September 30, 2017, 02:37:53 AM
Just to update, I've resolved the issue by removing the parallel R as above and altering the R24 value to compensate for the loss in voltage gain.

I'd suggest to anyone looking to build to avoid using a parallel R across a _series string_ rotary. My circuit has no audible max cut between between step positions as suggested in Harpo's V2 worksheet and I am using 23 step shorting type rotaries.

Thanks for the advice Harpo, appreciate it as always, learnt a lot about this circuit by simulating it (and of course your shared analysis of the circuit in your excel document!).
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: imloggedin on November 11, 2017, 01:28:47 AM
I just finished my Nite EQ and everything works but the middle of each pot is not flat - which I can deal with by adjusting the knobs, but the right channel is also 0.5-1 DB lower than the left. I wanted to use it as a stereo eq and I am not sure if swapping the opamps might help even out the levels. Any suggestions?

Thanks
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on November 11, 2017, 08:20:07 PM
I just finished my Nite EQ and everything works but the middle of each pot is not flat - which I can deal with by adjusting the knobs,

Hi, did you read this thread?

All the problems you're having are described in this thread and the solutions given

For the all the center points of each pot to be 0dbs you need to adjust resistor value on each pot.
there's an excel doc made by harpo that does the calculation, the doc it's in this thread
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: imloggedin on November 11, 2017, 08:58:42 PM
Hi, did you read this thread?

All the problems you're having are described in this thread and the solutions given

For the all the center points of each pot to be 0dbs you need to adjust resistor value on each pot.
there's an excel doc made by harpo that does the calculation, the doc it's in this thread

I ended up reading almost all of the pages after I posted and realized that. Sorry for the premature post. I am looking to do stepped switches instead of pots after reading all of the pot issues. Now if I can find the page that spreadsheet was on!

Thanks
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: imloggedin on November 11, 2017, 09:58:19 PM
Harpo's Stepped Pot spreadsheet is very helpful but it seems I would need a 21 step rotary switch to get from -5 to +5 in 0.5 db increments. Those don't seem to be very available or cheap so I guess I'll be sticking to pots until I find some.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: bruno2000 on November 11, 2017, 10:04:22 PM
Harpo's Stepped Pot spreadsheet is very helpful but it seems I would need a 21 step rotary switch to get from -5 to +5 in 0.5 db increments. Those don't seem to be very available or cheap so I guess I'll be sticking to pots until I find some.

https://www.ebay.com/itm/2Pole-23-Step-Rotary-Switch-Attenuator-Volume-Control-Pot-Potentiometer-DIY-New-/251286602182?_trksid=p5731.m3795

https://www.ebay.com/itm/1x-4Pole-23step-24Step-Rotary-Switch-DIY-Attenuator-Volume-Control-Shaft-6-0mm/292028066313?hash=item43fe3aaa09:g:FDIAAOSw5cNYfKtg

Best,
Bruno2000
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on November 11, 2017, 10:14:49 PM
I ended up reading almost all of the pages after I posted and realized that. Sorry for the premature post. I am looking to do stepped switches instead of pots after reading all of the pot issues. Now if I can find the page that spreadsheet was on!

Thanks

You don't need switches, pots work fine. I did a lot f builds already always with pots and the center position was spot on after  replacing the resistors using the spreadsheet.

If you didn't find the spreadsheet in this thread it's because you still didn't all, lol
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: mrdarwin on December 27, 2017, 11:51:42 AM
Hi!
I feel confused with balanced or unbalanced...
Started to wire the unit with balanced jumper, as I'd like to use the unit  with analog inserts with pro tools and an orion 32 (in/out +4dB balanced) but I have -6dB loss... I've read some posts about tweaking some resistors but what about other users?
When I removed the jumpers, here is a little loss... but unit is unbalanced...

I know the difference between balanced  and unbalanced, with wires with 2 or 3 connectors (xlr)...

Can I have some help please? or a link?
thx
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on December 27, 2017, 01:29:46 PM
Hi!
I feel confused with balanced or unbalanced...
Started to wire the unit with balanced jumper, as I'd like to use the unit  with analog inserts with pro tools and an orion 32 (in/out +4dB balanced) but I have -6dB loss... I've read some posts about tweaking some resistors but what about other users?
When I removed the jumpers, here is a little loss... but unit is unbalanced...

I know the difference between balanced  and unbalanced, with wires with 2 or 3 connectors (xlr)...

Can I have some help please? or a link?
thx

I don't know if I completely understand your questions



Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: mrdarwin on December 27, 2017, 01:39:28 PM
 :)
Unit finished, balanced jumper, true bypass relays boards, -6dB loss with pots in middle position
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: mrdarwin on December 27, 2017, 01:54:51 PM
How work the jumpers? Do they affect the gain?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on December 27, 2017, 03:33:04 PM
How work the jumpers? Do they affect the gain?

What pots did you use?

Did you adjust the middle position gain of the Pots?

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: mrdarwin on December 27, 2017, 04:12:33 PM
I use 470k rev log pots with center detent from AML.
Even if the unit is in bypass (not hardbypassed), I dont have unity gain... is it normal?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on December 28, 2017, 12:49:42 AM
I use 470k rev log pots with center detent from AML.
Even if the unit is in bypass (not hardbypassed), I dont have unity gain... is it normal?

I don't think so.

you should check all the resister values you used.

Could be possible that you might got some value wrong.

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on December 28, 2017, 01:04:34 AM
...When I removed the jumpers, ...
You need both jumpers on board. For balanced connection the center pin and right pin gets shorted on both jumper blocks, for unbalanced connection the center pin and left pin gets shorted on both jumper blocks. One jumper sets the connection of XLR-pin3, the other changes a feedback resistor value by paralleling another resistor. Difference is 6dB.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: mrdarwin on December 28, 2017, 01:14:13 AM
With no jumper signal is present with more gain than with balanced jumpers...
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on December 28, 2017, 01:26:30 AM
With no jumper signal is present with more gain than with balanced jumpers...

Check all the components and connections in the output circuit

Schematic attached
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: mrdarwin on December 28, 2017, 03:11:23 AM
 everythings look ok...
unity gain with no jumper (bypass) and -6db with j7 unbalanced. j3 changes nothing...
I use 470uF 25v... could this be the problem?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on December 28, 2017, 05:36:34 PM
I use 470uF 25v... could this be the problem?

Depends on where did you use that, if you used it in C13 then might not be that nice.

As far as I can see 470uF 25v are for:
C1
C14
C15
C29
C30
C40
C41
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: mrdarwin on December 29, 2017, 02:15:22 AM
I use a 22pf cog for c13.
I 'm asking about c1, c14, c15 because of the voltages of capacitors. In bom they're labelled 63v to withstand phantom... but I use any phantom power.

Anyway the unit seems to work now, it has a different behavior with Smaart Analyser and audio in from PTools...
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on December 29, 2017, 07:26:55 AM
I 'm asking about c1, c14, c15 because of the voltages of capacitors. In bom they're labelled 63v to withstand phantom... but I use any phantom power.

Well this unit should never receive phantom power, only condenser mics should receive p48V from a mic pre.
The unit sould be always connected to a Line input (line inputs dont have phantom)

Capacitor voltages will not affect the audio.
It just says an aproximate max limit of the voltage the capacitor can withstand
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on December 29, 2017, 07:39:00 AM
I'm finishin an unit at the moment,
just giving the final calibration touches.

There is something that I would like to call attention for.
In Harpo tweaking Excel sheet it says
"The C13 cap (actually 22pF) in the feedback loop of this summing stage for bandwidth limiting, set for -3dB cutoff at 128kHz, may be lowered to 15 or 18pF to get similar results in case R fb is upped. (-3dB lpf = 1/(2*pi() * R30 * C13)"

In my case R fb had to be upped in both channels, the original value was 56.2K, and I had 63.8K and 61.6.
So I did what Harpo suggested in the sheet and lowered the value of C13 to 18pf and 15pf.
Well I don't advise doing this as with both 18pf and 15pf I had low end loss when I turned the EQ on (compared to bypass mode).
With the original 22pf value the Low end stays the same when you change from bypass to EQ on, so I would stick with the value and not lower C13 even if you have to increase the vaue of R fb.

Or maybe there was something I didnt got right and Harpo can step in and help

Thank you Harpo for the great document and thanks everyone
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on December 29, 2017, 11:07:50 AM
everythings look ok...
unity gain with no jumper (bypass) and -6db with j7 unbalanced. j3 changes nothing...
I use 470uF 25v... could this be the problem?
I don't think so.
You seem to be measuring VAC output level between XLR-pins 1/2 and/or pins 1/3.
XLR-pin-1 is not involved in this measurement. You measure AC voltage between XLR-pins 2/3.
With your 'no jumper' version, XLR-pin-3 is not connected at all ...
For your 470uF/25V for C14 and C15 these would need a voltage rating of 35VDC in order to withstand a reverse kick in the butt from accidently activated phantom voltage.
48VDC * 1,1 for +/-10% phantom tolerance / (6k8 + 10k) * 10k = 31.4VDC
Some AD/DA converters come with built in mic-preamps and phantom supply that might be activated, so this isn't an only academic problem, but as always YMMV.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on December 29, 2017, 11:29:14 AM
..."The C13 cap (actually 22pF) in the feedback loop of this summing stage for bandwidth limiting, set for -3dB cutoff at 128kHz, may be lowered to 15 or 18pF to get similar results in case R fb is upped. (-3dB lpf = 1/(2*pi() * R30 * C13)"
This 22pF cap (I'd put in an additional 22pF cap) better would be connected between U5-pins 5/8 (a pcb has a backside) for unity gain compensation, because a NE5534 isn't unity gain stable. Unstable opamp in this context would be the only reason for low end loss I could forsee. An increase/decrease of C13 would mainly change the >100kHz high end perception of bats, as long as you don't operate this stage beyond its GBW and power bandwidth limits.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: mrdarwin on January 07, 2018, 02:16:31 PM
Hi!
A last question...My unit is powered with the green psu and two +15/-15v...
The original is 18v, Maag is 18v etc...
Datasheet of ne5532/34 says these can be powered with 12 to 20v if I remember correctly...
Does the value of  the rails affects the sound? I can easily change the resistors of lm317/337 on the psu pcb if its necessary...
Thanks again
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on January 08, 2018, 01:52:12 AM
A last question...My unit is powered with the green psu and two +15/-15v...
The original is 18v, Maag is 18v etc...
I can easily change the resistors of lm317/337 on the psu pcb if its necessary...

Yes, you should do that and run the unit from +-18v

I installed 2 trimpots to adjust the regulators output to + and - 18v, other people have done the same.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: steves.mastering on May 08, 2018, 03:48:25 PM
Hi,

I'm now hooking up my LM317/337 PSU, and for some reason I cannot achieve more than +/- 10V.

I am using this toroid - Triad - VPT30-830. Connected Primaries in series. secondary's parallel.  (Black and Orange tied together and Red and yellow tied together).

Any suggestions why the adjustable PSU seems to stop as soon as I reason +/-10v? thought these went up to 37V?

I have another Toroid I'm tempted to try but wasn't sure if I was missing something obvious.

cheers.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: druu on June 07, 2018, 08:33:59 AM
Hi,

I'm now hooking up my LM317/337 PSU, and for some reason I cannot achieve more than +/- 10V.

I am using this toroid - Triad - VPT30-830. Connected Primaries in series. secondary's parallel.  (Black and Orange tied together and Red and yellow tied together).

Any suggestions why the adjustable PSU seems to stop as soon as I reason +/-10v? thought these went up to 37V?

I have another Toroid I'm tempted to try but wasn't sure if I was missing something obvious.

cheers.

You need to have the secondaries in series with centre tap (CT) for 0V reference. This should provide you with the right voltages.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dasnevestheo on July 06, 2018, 02:49:24 PM
Hi there,
been poking around this thread for a while and gather loads of great info  :D
But i'm still looking for some panel info. I suck at DIYing panels so i'm looking for a FPD file or someone i could buy a panel.

Thanks !
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Le Roux on July 15, 2018, 04:09:59 PM
Awesome EQ!

Dead quiet, sounds great!

Thanks for the project!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: lautamei on January 02, 2019, 10:43:32 AM
This 22pF cap (I'd put in an additional 22pF cap) better would be connected between U5-pins 5/8 (a pcb has a backside) for unity gain compensation, because a NE5534 isn't unity gain stable. Unstable opamp in this context would be the only reason for low end loss I could forsee. An increase/decrease of C13 would mainly change the >100kHz high end perception of bats, as long as you don't operate this stage beyond its GBW and power bandwidth limits.

Hi, my build it's working fine, but my bypass it's not a real "bypass". It's cutting of some low end. You think that the problem it's on C13 cap?

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on January 04, 2019, 01:07:39 PM
Hi, my build it's working fine, but my bypass it's not a real "bypass". It's cutting of some low end. You think that the problem it's on C13 cap?

Which pots did you use?
Did you use Harpo's doc to get the resistor values to adjust the center values of your pots?
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: weiss on February 09, 2019, 09:33:05 AM
does someone own a .fpd frontpanel file which fits the pcb print?  :)
don't want to buy from purusha
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on February 09, 2019, 09:48:14 AM
don't want to buy from purusha

Yes, Nice!

A friend of mine did a great looking front pannel for his unit, I will ask him the files and send it to you

please pm me your email

regards
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: weiss on February 09, 2019, 09:56:29 AM
Yes, Nice!

A friend of mine did a great looking front pannel for his unit, I will ask him the files and send it to you

please pm me your email

regards
thanks a lot! your mailbox is full  ;-)
sent you a mail
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: dasnevestheo on February 09, 2019, 02:35:43 PM
so did I ;)
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: weiss on February 11, 2019, 09:23:02 AM
Yes, you should do that and run the unit from +-18v

I installed 2 trimpots to adjust the regulators output to + and - 18v, other people have done the same.

Hi,

Could you help me which ones you used and where exactly to put it?

Appreciate your help!
Ansgar
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on February 11, 2019, 09:28:11 AM
I don't have the schematic here with me,
please post the schematic of the green psu and I will tell you.

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: weiss on February 11, 2019, 09:43:01 AM
I don't have the schematic here with me,
please post the schematic of the green psu and I will tell you.

here the schematic: http://fucanay.fischerworks.com/diy/_Green_PSU_Schem.GIF
here is the layout of the pcb
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Whoops on February 11, 2019, 09:50:46 AM
HI Weiss,
LM317 and LM337 are adjustable voltage regulators.

Check their datasheet on how to install a trimpot

check also the implementation of these regulator in the JLM PSU:

http://www.jlmaudio.com/ACDCVer2sch.pdf


I think in mine I just replaced R1 and R5 for a 5K Multiturn Trimpot
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: weiss on February 11, 2019, 10:02:01 AM
HI Weiss,
LM317 and LM337 are adjustable voltage regulators.

Check their datasheet on how to install a trimpot

check also the implementation of these regulator in the JLM PSU:

http://www.jlmaudio.com/ACDCVer2sch.pdf


I think in mine I just replaced R1 and R5 for a 5K Multiturn Trimpot

thank you!
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: jrasia on April 15, 2019, 07:06:48 PM
I'm using a DIY Racked PCB of this EQ, and have a particular question about 60hz hum I'm getting.

Ch1 is very quiet. 
Ch2 is fine so long as I have the 'Air' switch on.  When its in 'Off' position, I'm getting the 60hz noise. 

I have Mumetal around the transformer, tried rotating it with no change.  Audio cabling is all shielded.  All wiring is nicely twisted and moved away as far as possible from the psu.

Any ideas?

Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: lukas on April 16, 2019, 04:55:47 AM
Yeah...bad power supply.
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: Harpo on April 16, 2019, 07:06:08 AM
I'm using a DIY Racked PCB of this EQ
assume your schematic and pcb to differ from this topics schematic and pcb.

Quote
Ch2 is fine so long as I have the 'Air' switch on.  When its in 'Off' position, I'm getting the 60hz noise.
So this seems pre psu related. (Post psu would be dominant 120Hz from rectification).
Double check traceside of pcb. There might be a wire not clipped off that now connects to your case ground.
Other possibility might be a device inducing mains frequency into your eq with lid open. (halogen spot, ...)
Good luck
Title: Re: 3D "AIR" EQ - "Night EQ" PCB's Complete!
Post by: jrasia on April 16, 2019, 08:32:00 PM
Thanks guys!  I'll have t