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Project Specific Discussions => Filters/Equalizers => Topic started by: peter purpose on February 04, 2010, 01:18:50 PM

Title: EQN build thread
Post by: peter purpose on February 04, 2010, 01:18:50 PM
Everything is ordered, so let's start with a BOM.
http://lazpro.com/eqnbom.pdf
I think it's all there.
Title: Re: EQN build thread
Post by: peter purpose on February 08, 2010, 02:03:27 AM
Sorry girls, but I couldn't NOT share.
Skylar has rendered up a front panel with some custom knobs.... and I had to knock one out.

(http://lazpro.com/lazeqn.jpg)
Title: Re: EQN build thread
Post by: RedNoise on February 08, 2010, 04:36:49 AM
Woww!!Really nice color mariage !
Title: Re: EQN build thread
Post by: peter purpose on February 08, 2010, 08:51:11 AM
Also... just got word from Ed that transformer production is about to start.
Title: Re: EQN build thread
Post by: Snatchman on February 08, 2010, 12:20:59 PM
Sorry girls, but I couldn't NOT share.
Skylar has rendered up a front panel with some custom knobs.... and I had to knock one out.

(http://lazpro.com/eqnren.jpg)
Dang..... :o...Bootiful.....
Title: Re: EQN build thread
Post by: bdubya on February 08, 2010, 01:08:00 PM
Yeah, that's purty
Title: Re: EQN build thread
Post by: peter purpose on March 19, 2010, 03:34:54 PM
Children.... Daddy has sent all the parcels, but if you're an ealy recipient.... The small resistors and toggle switches go on the underside.

Play nicely
Title: Re: EQN build thread
Post by: kazper on March 19, 2010, 06:06:55 PM
Just a guess he is talking about the resistors that are shown in the outline of the greyhill switches. If you mount them on the top side the switch is a no go. Same thing with the toggle switches if you want them to fit in there place out front.
Title: Re: EQN build thread
Post by: peter purpose on March 20, 2010, 12:52:59 AM
Were we meant to get some small resistors?
No.... resistors are down to you.
Are the rocker switches, the two little switches in the kit you sent?
Oh dear...I have an awful feeling.
On your BOM, if it does not have the voltage or wattage written on the components, what are the recommended minimum. Like on some of the capacitors, it does not state the voltage size and the resistors does not state the wattage.
1/4 watt unless specified for the resistors. Power caps need to be 25v minimum.
Will there be any wiring or special style of build process involved in this build? I can see that the 3 little pots are wired from one of your pics. How is the wiring on this build?
I'll stick up some diagrams...don't panic.
Can you please post up an eagle eye view top and bottom, nice and close and clear of the final finished build for visual reference.
Ahhh....That's how I started too.
Will this unit need to be calibrated in some way like the 1176?
It will
Here is a pic of my kit that I received. Anyone notice anything missing on it?
Jayzus Manny.... Check the thread in the white market. The kit contents are noted.
Title: Re: EQN build thread
Post by: canidoit on March 20, 2010, 02:24:22 AM
Please feel free to check my journey thread for an Excel BOM and some quick visual references and information I gathered regarding this build.

http://www.groupdiy.com/index.php?topic=38884.msg479573#msg479573 (http://www.groupdiy.com/index.php?topic=38884.msg479573#msg479573)
Title: Re: EQN build thread
Post by: peter purpose on March 20, 2010, 02:27:22 AM
Small amp details.

QI BC184C
Q2 BC184C
Q3 BC184C
C1 10UF TANT
C2 22UF TANT
C3 47PF COG/NPO CAN BE LEFT OUT
C4 470PF COG/NPO
C5 680PF COG/NPO
C6 1NF COG/NPO
C7 22UF TANT
C8 68UF/10V
R1 27K
R2 3K3
R3 39K
R4 3K6
R5 180K
R6 120K
R7 820R
R8 180K
R9 3K9
R10 100K

(http://lazpro.com/ampol.jpg)
Title: Re: EQN build thread
Post by: peter purpose on March 20, 2010, 02:55:58 AM
*SYMBOL DENOTES NOT NEEDED FOR 51X
**SYMBOL DENOTES SUPPLIED WITH KIT

Right there at the top of the BOM.

Get your chit together Manny..!!
Title: Re: EQN build thread
Post by: peter purpose on March 20, 2010, 02:57:15 AM
Bit of info.

(http://lazpro.com/xinf.jpg)
Title: Re: EQN build thread
Post by: peter purpose on March 20, 2010, 03:17:13 AM
btw.. you'll notice that the potentiometer holes in the faceplate are counter bored. This is so that you fix the pots to the shelf and the nuts are hidden.
Title: Re: EQN build thread
Post by: Slenderchap on March 20, 2010, 03:21:52 AM
I put together a partial kit which contains the film capacitors ...... they are mostly Wimas.... but there are a couple which I could not get at short notice so I have used the Dubilier ones which we stock anyway ..... 1n5 and 15nF..... the 15nF's are only 5mm pitch so a bit of "leg extension" will be needed.

Colin
www.audiomaintenance.com
Title: Re: EQN build thread
Post by: peter purpose on March 20, 2010, 03:32:31 AM
I am missing these 8X .8MM SOCKETS FOR CC-6** * in my kit by the looks of it.

I can see them in your pic. They have to be removed from the strip.
But they're not needed if you're a 51x boy.

(http://lazpro.com/socket.jpg)
Title: Re: EQN build thread
Post by: peter purpose on March 20, 2010, 03:59:39 AM
All the 4M7 mini resistors should have their legs cut so as to not protrude through the top surface.
Solder them on the underside.

(http://lazpro.com/minires.jpg)

(http://lazpro.com/mr.jpg)
Title: Re: EQN build thread
Post by: peter purpose on March 21, 2010, 12:43:37 PM

---------------------------------------------------------------------------

(not written in March BOM - eqnbom.pdf)


What the f**k are you on about? It's at the bottom.
Title: Re: EQN build thread
Post by: jsteiger on March 21, 2010, 07:46:30 PM
What the f**k are you on about? It's at the bottom.
I for one am quite offended by such language Peter. I actually think I want my money back for these 1084's.  ???





------------------------------------------------------------------------------------------------------
Just kidding. I rather like when you talk dirty!  :D :D :D :D :D :D :D

BTW, can we track that tortoise??

Cheerio, Jeff  ;D




Title: Re: EQN build thread
Post by: desol on March 21, 2010, 09:14:27 PM
To come to his defense, canidoit asks alot of unneccessary questions imo, which i feel can get annoying for some, distracting and shows certain amounts of disrespect. Whether he/she's aware of this or not. Canidoit needs to start screening their questions as to whether they are necessary/valid or not, imo...and start reasearching common sense information beforehand. Better judgement. There comes a point when this type of information starts to take away from a thread, and as i suggested, can be distracting or even misleading.

A star is useful when swearing. ie: F*ck.  (burp)
Back to my gin and tonic. Cheers all...and no disrespect to anyone.
Title: Re: EQN build thread
Post by: peter purpose on March 22, 2010, 02:42:30 AM
I rather like when you talk dirty!

You know I do it just for you Jeff.
Title: Re: EQN build thread
Post by: peter purpose on March 22, 2010, 02:43:47 AM
A star is useful when swearing. ie: F*ck.  (burp)

Bollocks * ... like that?
Title: Re: EQN build thread
Post by: canidoit on March 22, 2010, 03:24:57 AM
To come to his defense, canidoit asks alot of unneccessary questions imo, which i feel can get annoying for some, distracting and shows certain amounts of disrespect. Whether he/she's aware of this or not. Canidoit needs to start screening their questions as to whether they are necessary/valid or not, imo...and start reasearching common sense information beforehand. Better judgement. There comes a point when this type of information starts to take away from a thread, and as i suggested, can be distracting or even misleading.

A star is useful when swearing. ie: F*ck.  (burp)
Back to my gin and tonic. Cheers all...and no disrespect to anyone.

People who start out, dont know some of these common sense stuff. Like Q1, Q2, Q3. Im just trying to help myself and people who arent as knowledgable as some of you guys. It's not being disrespectful if someone really does not know and wants to post an enquiry. Do you expect me to do a search on what 3 asterisk means on Peters BOM list or what part is what when non of the parts provided are labeled. I am already struggling trying to find the parts using the search function at the stores. I have no idea what some of these parts looks like that are in the BOM even after doing a search. I thought this thread is about questions about this build.
Title: Re: EQN build thread
Post by: peter purpose on March 22, 2010, 08:12:15 AM
Manny....just engage brain before opening gob and it'll go much more smoothly.
Title: Re: EQN build thread
Post by: peter purpose on March 22, 2010, 08:14:25 AM
In another thread Volker asked "what size do I have to use?" when referring to potentiometers.

Small format... ie Vishay PRV6/PARV6 kinda size.
Title: Re: EQN build thread
Post by: boji on March 22, 2010, 11:08:12 AM
We've all been there canidoit.  I've posted plenty of headsmackingly obvious questions, it's just part of the learning process.
Just take your licks from the intelligentsia, muster up some humility and read everything thrown at you, like, five times.
Sleep on it, read it again, then, if your still chaseing butterflies, post.     :P


Title: Re: EQN build thread
Post by: desol on March 22, 2010, 11:12:21 AM
A star is useful when swearing. ie: F*ck.  (burp)

Bollocks * ... like that?

No, like this>>> What the f*** are you on about?
Or, s**t, I just burnt my new remote control with the soldering iron.
Kinda like that, or kinda not, whichever.
Title: Re: EQN build thread
Post by: peter purpose on March 22, 2010, 12:44:15 PM
Right... I think I get it... cough.
Title: Re: EQN build thread
Post by: jsteiger on March 23, 2010, 08:10:07 AM
Kits received Peter. Thanks!

Just ordered 2 partial parts kits from Colin. Nice and easy.  ;D

Now, Mike and Ed were is the rest-o-the iron???  ::)

Looking forward to bugging the piss out of you on this one Peter!  :D

I kid.  ;)

Cheers, Jeff  :)
Title: Re: EQN build thread
Post by: peter purpose on March 23, 2010, 08:42:23 AM
Looking forward to bugging the piss out of you on this one Peter!  :D

Looking forward to ignoring you.
Title: Re: EQN build thread
Post by: technut on March 25, 2010, 07:23:21 PM
Got mine today! Thanks to peter and colin for all their help so far!
Title: Re: EQN build thread
Post by: zayance on March 25, 2010, 09:18:03 PM
Sorry girls, but I couldn't NOT share.
Skylar has rendered up a front panel with some custom knobs.... and I had to knock one out.

(http://lazpro.com/lazeqn.jpg)

Those knobs look a lot like the Kilo international DDS type knobs, looks great.
Title: Re: EQN build thread
Post by: canidoit on March 30, 2010, 09:48:13 PM
Does the minimal calibration process for this unit require an Oscilloscope? Can you get this unit running at its best without one?

I am in the process of considering buying one and I need to know if I should buy it for this build? My Oscilloscope may be out of calibration though since it will be old but maybe it will be sufficient enough for this build.

Thanks
Title: Re: EQN build thread
Post by: peter purpose on March 31, 2010, 08:40:14 AM
Search for a free software scope. That'll be sufficient for your needs.
Title: Re: EQN build thread
Post by: johnnyscotch on April 09, 2010, 02:29:11 AM
Everything is ordered, so let's start with a BOM.
http://lazpro.com/eqnbom.pdf
I think it's all there.

This might be a stupid question, and I'm sure more will follow, but here goes:

All 1/4w resistors unless noted otherwise?

I'm putting my parts order together as I type this.....

cheers!
Title: Re: EQN build thread
Post by: canidoit on April 09, 2010, 06:59:08 AM
Everything is ordered, so let's start with a BOM.
http://lazpro.com/eqnbom.pdf
I think it's all there.

This might be a stupid question, and I'm sure more will follow, but here goes:

All 1/4w resistors unless noted otherwise?

I'm putting my parts order together as I type this.....

cheers!
Yes that's right,
"They are 1/4 watt unless specified for the resistors.
Power caps need to be 25v minimum."

All the best with the parts mate, if you manage to gathers all your parts, can I please have a look at your store BOM list to reference from. :)

Title: Re: EQN build thread
Post by: Denyle Guitars on April 09, 2010, 10:59:15 AM
Quote
They are 1/4 watt unless specified for the resistors.

Including the mini's? So far I've only been able to find those in 1/8w.
Title: Re: EQN build thread
Post by: johnnyscotch on April 09, 2010, 05:26:10 PM
Quote
They are 1/4 watt unless specified for the resistors.

Including the mini's? So far I've only been able to find those in 1/8w.

Oh, yeah, what about those??

1.7mm, is that "mini"??

I'm looking on Mouser.........
Title: Re: EQN build thread
Post by: kazper on April 10, 2010, 12:00:56 AM
The 4M7 (Mini) resistors should be fine as 1/8W.

Title: Re: EQN build thread
Post by: johnnyscotch on April 10, 2010, 12:10:49 AM
So, about the "mini" part, do you reckon these will fit the bill?
http://www.mouser.com/ProductDetail/Xicon/299-47K-RC/?qs=sGAEpiMZZMsCQIGbZVRXMFXYoRLDbKp7wdcuiFDfqis%3d (http://www.mouser.com/ProductDetail/Xicon/299-47K-RC/?qs=sGAEpiMZZMsCQIGbZVRXMFXYoRLDbKp7wdcuiFDfqis%3d)
Title: Re: EQN build thread
Post by: kazper on April 10, 2010, 12:50:30 AM
The leaded holes are over 6mm so it has more do do with the width of the part.. Buy 200 of what you found and send me some.

Here is some from newark as well
http://www.newark.com/multicomp/mccfr0w4j0475a50/res-carbon-film-4-7mohm-250mw-5/dp/58K5059
Digikey
1/6W
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=4.7MEBK-ND
1/8W
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=CF1/84.7MJRCT-ND
Title: Re: EQN build thread
Post by: peter purpose on April 10, 2010, 12:00:50 PM
Guys... I use RS part 136-115P... anything along those lines will do you nicely.
Title: Re: EQN build thread
Post by: kazper on April 11, 2010, 10:12:57 PM
Peter,

What was the part number for the DC/DC thing incase someone wants to hang that way? Helping someone find parts for there build, and I passed on by it wherever it is...

Kaz

Title: Re: EQN build thread
Post by: jsteiger on April 11, 2010, 11:26:52 PM
Peter,

What was the part number for the DC/DC thing incase someone wants to hang that way? Helping someone find parts for there build, and I passed on by it wherever it is...

Kaz


Kaz,

It's TDK LAMBDA CC6-2412DF-E from Peter's BOM.

Cheers, Jeff
Title: Re: EQN build thread
Post by: kazper on April 11, 2010, 11:47:07 PM
Peter,

What was the part number for the DC/DC thing incase someone wants to hang that way? Helping someone find parts for there build, and I passed on by it wherever it is...

Kaz


Kaz,

It's DC-1 TDK LAMBDA CC6-2412DF-E from Peter's BOM.

Cheers, Jeff

Woahhh apparently I'm smoking something and just don't know it. Thanks for the number though.


Bad news is it's coming up as a obsolete part now....at least on mouser
Title: Re: EQN build thread
Post by: fazeka on April 14, 2010, 06:21:00 PM

Bad news is it's coming up as a obsolete part now....at least on mouser


Others (Digikey, etc.) have it listed not as obsolete, but out of stock...

Expensive little bugger - $15.
Title: Re: EQN build thread
Post by: briomusic on April 22, 2010, 03:44:49 PM
having some problems tracking down the bc184c at my usual places...
is the bc549c an ok replacement?
a quick look at the datasheet revealed that the bc184c has/likes a collector current of 500ma and the bc549c only 100mA. That a problem?

thanks!
Title: Re: EQN build thread
Post by: Grooveteer on April 22, 2010, 03:59:41 PM
I bought my BC184Cs from these guys:

http://cgi.ebay.com/BC184C-BC184-Transistors-Sinclair-Computers-10-Pack-/250616104735?cmd=ViewItem&pt=UK_VintageComputing_RL&hash=item3a59e2471f

Cheers,

G
Title: Re: EQN build thread
Post by: Denyle Guitars on April 22, 2010, 04:00:58 PM
Is the API 2623 cool for the output transformer?
Title: Re: EQN build thread
Post by: briomusic on April 22, 2010, 04:38:14 PM
Is the API 2623 cool for the output transformer?

I think a custom made tranny based on the LO1166 is in the works and will be sold by hairball audio.

as for the small format pots....having trouble finding the PRV6 series, but found RV6 instead:
will this one fit the bill?
http://uk.rs-online.com/web/search/searchBrowseAction.html?method=searchProducts&searchTerm=2508745105&x=0&y=0 (http://uk.rs-online.com/web/search/searchBrowseAction.html?method=searchProducts&searchTerm=2508745105&x=0&y=0)
or indeed this one?
http://www.banzaimusic.com/Alpha-9-PC-NUT-10k-lin.html?quantity=1 (http://www.banzaimusic.com/Alpha-9-PC-NUT-10k-lin.html?quantity=1)
Title: Re: EQN build thread
Post by: briomusic on April 29, 2010, 04:35:23 AM
Hi Peter,
starting to populate the board now - very comfortable to solder!
Thanks for the crucial advice regarding the mini resistors.

Would you care to elaborate on the following bits....
R29 TBD gain set -how to determine this value?
R18 220k not used -this means just leave out, not a jumper right?
R17 2k7/6k8 -again how do I determine the correct value?
I guess the amp-pins need to be bent by 90 degrees to fit the sockets,
would be great if you have a picture that shows how it's done right.
RV4/5 -what is the alignment procedure for these trimmers? is it similar to the 'symmectrical clipping' process on the 1290 preamp?

Cheers
Briomusic

ETA one more question regarding the orientation of the 68uF on the ampboard...on this picture:(http://lazpro.com/ampol.jpg)
C8 has the plus sign on the left and slightly to the bottom, on the actual ampboard this cap is positioned vertically, so just to verify, plus side pointing towards/or away from the connector pins?
Title: Re: EQN build thread
Post by: Denyle Guitars on April 29, 2010, 04:11:27 PM
I think the plus side goes in, the ground is closer to the edge of the pcb.
Title: Re: EQN build thread
Post by: briomusic on April 30, 2010, 06:17:04 PM
Thanks denyle, had a look at the BA284 schematics and the traces on the pcb, and what you say makes sense!

Have you (or anyone else for that matter  :) ) had a chance to fire up your EQN yet? I am pretty close to finishing, but am a bit weary about powering up without answers to the questions above.
Title: Re: EQN build thread
Post by: briomusic on May 01, 2010, 02:18:00 PM
well as my 'journey' continues (unfortunately currently a journey without 'purpose', geddit)
i actually powered up today - no smoke  :D
i am even getting some very tinny sounding audio, which disappears when i disable the eq
(it's obviously not a hard-bypass, I am still trying to figure out what the 'eq in' switch does, not easy without schematics etc...)
however, all the frequency bands seem to be working i can boost and cut to my hearts content, can't really make any judgement about the sound as something is clearly going wrong somewhere.
I swapped the 'BA284'style ampboards for two different ones from the other kit - this didn't change anything.
I am currently looking at the input stage (is there even one? can't locate the BA283 that would be found on the original)
or output stage.
RV4 seems to be some sort of input level, RV5 seems to be the 'symmectrical clipping' adjuster same as in my EZ1290.

I can't believe noone is posting apart from me and denyle, I think quite a few kits were sold. come on guys, pipe up :)
(http://img.photobucket.com/albums/v426/brio/brioEQn1.jpg)
(the trafo is a VTB 1847 which I am using to test the eq while waiting for the EA1166)
Title: Re: EQN build thread
Post by: jsteiger on May 01, 2010, 02:41:29 PM
...I can't believe noone is posting apart from me and denyle...
We are all anxiously awaiting while yourself and Denyle pave the way...work out any kinks and so on!  ;D

I have yet to order the balance of my parts, aside from already receiving Colin's parts kit. I am trying to tie up a few other loose ends before starting more loose ends.  8)  I'm sure I speak for a few others too.

Keep up the good work guys. I hope you figure out the "tiny" sounding situation. Also, congrats on no smoke. That is always a plus.  ;)

I remember Denyle mentioning a 2623-1 for output tranny. Is there any DC present? Probably not good for a 2623-1if it's more than a few mA.

Cheers, Jeff
Title: Re: EQN build thread
Post by: peter purpose on May 03, 2010, 09:23:57 AM
Guys.... you wouldn't believe the chit I've been stuck under, but you now have my attention.
I'll start working through... let me wake up first.
Title: Re: EQN build thread
Post by: peter purpose on May 03, 2010, 09:34:22 AM
Would you care to elaborate on the following bits....
I'll have a pop
R29 TBD gain set -how to determine this value?
Depending on how the output transformer ratio ends up, we'll be using something from 600R-1k2.
We also have a fader trimmer to fine tune.
R18 220k not used -this means just leave out, not a jumper right?
Leave it out.
R17 2k7/6k8 -again how do I determine the correct value?
Different schematics have different values. This is the q setting resistor for the mid inductor. I used 6k8.
I guess the amp-pins need to be bent by 90 degrees to fit the sockets,
would be great if you have a picture that shows how it's done right.

I'll get a pic up.
RV4/5 -what is the alignment procedure for these trimmers? is it similar to the 'symmectrical clipping' process on the 1290 preamp?
Exactly.
Title: Re: EQN build thread
Post by: peter purpose on May 03, 2010, 09:56:28 AM
well as my 'journey' continues (unfortunately currently a journey without 'purpose', geddit)
Chortle
i actually powered up today - no smoke
Marvellous 
i am even getting some very tinny sounding audio, which disappears when i disable the eq
(it's obviously not a hard-bypass, I am still trying to figure out what the 'eq in' switch does, not easy without schematics etc...)

I'll get an abortion of a schematic up...... I've been avoiding it like the plague.
however, all the frequency bands seem to be working i can boost and cut to my hearts content, can't really make any judgement about the sound as something is clearly going wrong somewhere.
No answer to that until I get my thinking cap on.
I swapped the 'BA284'style ampboards for two different ones from the other kit - this didn't change anything.
ditto
I am currently looking at the input stage (is there even one? can't locate the BA283 that would be found on the original)
or output stage.

The input tx's output goes to the eq in switch and from there either to the eq section, or the output stage.
RV4 seems to be some sort of input level, RV5 seems to be the 'symmectrical clipping' adjuster same as in my EZ1290.
RV4 is the fader. It's sets the level going to the output stage. RV% is as you say.
Title: Re: EQN build thread
Post by: peter purpose on May 03, 2010, 09:59:09 AM
Is the API 2623 cool for the output transformer?

Absolutely not.... you need a gapped job to handle the current drive.
Title: Re: EQN build thread
Post by: briomusic on May 03, 2010, 02:07:03 PM
well as my 'journey' continues (unfortunately currently a journey without 'purpose', geddit)
Chortle

I am here all week!

i actually powered up today - no smoke
Marvellous  
i am even getting some very tinny sounding audio, which disappears when i disable the eq

update...R7 was disconnected, tinny sound now also present in bypass, albeit not eq'd  :D

(it's obviously not a hard-bypass, I am still trying to figure out what the 'eq in' switch does, not easy without schematics etc...)
I'll get an abortion of a schematic up...... I've been avoiding it like the plague.


allow me....
(http://img.photobucket.com/albums/v426/brio/eqnschem.gif)

I am currently looking at the input stage (is there even one? can't locate the BA283 that would be found on the original)
or output stage.

The input tx's output goes to the eq in switch and from there either to the eq section, or the output stage.


I am now pretty sure that I have an error right after the input transformer. Because: with out+ (of the input tran) connected to the pcb I have the tinny sound on the primary AND secondary of said input transformer, with that node disconnected I have normal sound on both sides (=> transformer seems fine). It seems I have an impedance problem or some sort of severe high pass filter on the secondary of the input transformer. (would that sorta thing also affect the primary side of an input transformer?)

Looking at the schematic there seem to be quite a lot of paths between the two nodes of the secondary winding (the lower one also being signal ground, AFAI understand) I am especially puzzled by R3 and R4 in parallel...is this to get a particular value?

Anyway, good to have you back, peter, and would love to see your abortion of a schematic, to compare and contrast with my reverse engineered abomination. :D

ETA: one more question, what's the jumper between the OT and the word 'london' for?
Title: Re: EQN build thread
Post by: Marcocet on May 03, 2010, 03:37:44 PM

as for the small format pots....having trouble finding the PRV6 series, but found RV6 instead:
will this one fit the bill?
http://uk.rs-online.com/web/search/searchBrowseAction.html?method=searchProducts&searchTerm=2508745105&x=0&y=0 (http://uk.rs-online.com/web/search/searchBrowseAction.html?method=searchProducts&searchTerm=2508745105&x=0&y=0)
or indeed this one?
http://www.banzaimusic.com/Alpha-9-PC-NUT-10k-lin.html?quantity=1 (http://www.banzaimusic.com/Alpha-9-PC-NUT-10k-lin.html?quantity=1)

Anybody have an answer for this one? The first ones look good to me but I don't trust myself. Thanks!

Title: Re: EQN build thread
Post by: briomusic on May 03, 2010, 04:25:36 PM
the second one is no good (6mm shaft), so I swapped it for this one:
http://www.banzaimusic.com/CTS-270-10k-LIN.html (http://www.banzaimusic.com/CTS-270-10k-LIN.html)
which just about fits after I clipped off some of the pcb material.

ETA: these pots eventually broke after my 'customisation'. ::) I ended up buying the PRV6's that this kit was designed for.
Title: Re: EQN build thread
Post by: Denyle Guitars on May 03, 2010, 05:16:21 PM
Quote
as for the small format pots....
I used Clarostat 308 series
Title: Re: EQN build thread
Post by: jsteiger on May 03, 2010, 05:25:42 PM
Tom,

You saw about the output iron didn't you? Just making sure.

Jeff
Title: Re: EQN build thread
Post by: Denyle Guitars on May 03, 2010, 05:36:10 PM
Tom,

You saw about the output iron didn't you? Just making sure.

Jeff

Yeah, I just measured 600+mv at the OT primary pad. I was mainly wondering about the ratio. I figured I could stick a cap on there for testing until Ed's are done.
Title: Re: EQN build thread
Post by: Marcocet on May 03, 2010, 07:34:41 PM
Thanks guys. I have one more newbie sourcing question

The 1N400x diodes: will 1n4001's cut it? was it not specified because any of the series will do?

Can't wait to get a look at the schematic.
Title: Re: EQN build thread
Post by: peter purpose on May 03, 2010, 09:40:24 PM
Thanks guys. I have one more newbie sourcing question

The 1N400x diodes: will 1n4001's cut it? was it not specified because any of the series will do?

Can't wait to get a look at the schematic.

1N4001 will do nicely.
Title: Re: EQN build thread
Post by: peter purpose on May 04, 2010, 08:24:56 AM
I am especially puzzled by R3 and R4 in parallel...is this to get a particular value?
No, but R4 39K can be left out. The prototype was fine with it.
what's the jumper between the OT and the word 'london' for?
That is to switch the R37/604R resistor accross the output transformer secondaries should you so wish.
On the underside are some pads for adding a zobel if we need one.
Title: Re: EQN build thread
Post by: peter purpose on May 04, 2010, 08:37:58 AM
The pins need to have a fairly close-up bend to the pcb.
The easiest way is to solder them in and then bend them.
Don't worry about roughing up the surface... it'll give extra grip in the sockets.

(http://lazpro.com/bend.jpg)
Title: Re: EQN build thread
Post by: briomusic on May 04, 2010, 10:04:12 AM
I am especially puzzled by R3 and R4 in parallel...is this to get a particular value?
No, but R4 39K can be left out. The prototype was fine with it.
what's the jumper between the OT and the word 'london' for?
That is to switch the R37/604R resistor accross the output transformer secondaries should you so wish.
On the underside are some pads for adding a zobel if we need one.

ok I am still not at peace with the input stage. I have now taken my 2nd kit and just soldered in part-by-part starting from the input transformer, all the while monitoring the secondary side with a little guitar amp. as soon as either R3 and/or R4 are connected, the sound gets really thin and quiet in a way that makes me think this can't be right. all this without power connected, just using the passive components up to R5 and R7.

just to confirm: I have the primary and the secondary side of the VTB9076 wired in series for 2:1 turn ratio.

peter, could you re-check and confirm the input stage on your schematic, I now have the exact same thing happening on two pcbs...

all the more frustrating, as on the first kit, I can hear the EQ working 'well' on the weirdly hpf'd signal
Title: Re: EQN build thread
Post by: peter purpose on May 04, 2010, 11:08:45 AM
(http://lazpro.com/itx.jpg)

As you can see... the input transformer needs to be wired 4:1... primaries in series and secondaries in para.
2 goes to IN+
5 goes to IN-
7&8 go to OUT+
9&10 go to OUT- Ground
Title: Re: EQN build thread
Post by: briomusic on May 05, 2010, 09:54:54 AM
Result! ;D ;D

After rewiring the input transformer to 4:1 and still struggling with the tinny sound, I decided to try using a different output from my interface (Digidesign 96 i/o) and all of a sudden everything was ok. Later on I will try and figure out why output 1 wouldn't play ball with my EQN and output 9 would  ???, but for now, let's just enjoy the sweet eq-ness.  ;D

Apart from this problem (which has to be blamed on my studio's wiring) this was really a very straight-forward kit to build (super minor gripe: the replacement screws for the input transformer are a little too long and need to be shortened which sometimes damages the threading). Also, I still would like to see a schematic whenever peter gets round to it.

I can't wait to try this eq in place of a unit built by a company that shares its name with a character out of friends.  ;)
especially with the added high frequencies. will report back later.....
Title: Re: EQN build thread
Post by: Slenderchap on May 05, 2010, 09:59:50 AM
I can't wait to try this eq in place of a unit built by a company that shares its name with a character out of friends.

Must be Phoebe Audio, or Monica Acoustics...

Title: Re: EQN build thread
Post by: strangeandbouncy on May 05, 2010, 10:31:53 AM
Hey Brio,


   Hope all is well with you!


  i have beeen having all kinds of trouble with our 192's, having made the assumption that they would drive an unbalanced input. They will, but only with one leg(cold) disconnected, and with an insertion loss of 6dB. They HATE having one leg shorted to ground. This might be your trouble(?). I'd check you wiring to see if that output is shorted/un-balanced somewhere.


     Kindest regards,



       ANdyP
Title: Re: EQN build thread
Post by: Holger on May 09, 2010, 07:44:50 AM
I don't have a 68µF C8 for the amp boards. Is it possible to use a 47µF or 100 µF instead wihtout getting punished?

Regards

Holger
Title: Re: EQN build thread
Post by: briomusic on May 09, 2010, 10:58:24 AM
my half-educated guess - this is not a pcb-bypass or decoupling cap, so I would be careful about simply changing that value to a larger one.
Title: Re: EQN build thread
Post by: briomusic on May 12, 2010, 01:18:14 PM
just one more bit of advice: put the stop pins into the grayhill switches before soldering them in. you won't be able to open them afterwards, as the filter caps are in the way.

(got that one wrong, pins go in from the front)

otherwise: great sound, very comparable to my 'other' commercially obtained neve copy
that said, I find it hard to do the top end of a female vocal sound with just neve-eqing, I feel that I need an 'air eq' or some plugin to get the really hi stuff. this applies to all 1073/84 eqs I have encountered.
I patched the EQN on various channels of a multitrack I had handy, and it was most helpful on drums and guitars - again typical neve behaviour :)

I'll definitely get two more if there is another round. ;D
Title: Re: EQN build thread
Post by: Grooveteer on May 12, 2010, 04:16:57 PM
Ok, time for one of my silly questions:  How are you insulating your MJE3055 from the heatsink? I usually use an insulation pad plus a grommet to insulate the bolt, but the screw that came with the heatsink is too large for the grommets I have.  Should the MJE3055 be insulated from the heatsink at all?

Thanks!
G
Title: Re: EQN build thread
Post by: Denyle Guitars on May 12, 2010, 05:41:29 PM
The heatsink isn't connected to the chassis so I didn't use an insulator.
Title: Re: EQN build thread
Post by: briomusic on May 12, 2010, 07:03:02 PM
me neither. the soldering is just to fix it in place, no electrical connection to anything.
Title: Re: EQN build thread
Post by: strangeandbouncy on May 12, 2010, 07:25:35 PM
Hi Brio,


  vv. "Air" on vocals. I guess it depends on the source. I am using Peter's prototype every day, Mostly on lead vocals. SOmetimes(normally on other people's recording) I need some additional sh*t, but where i am using my own recorded stuff, I am using it FOR the "air"(highest frequency setting) . . . . . , and something else for the "presence" . Mind you, I have a number of things I use to bring up the air over the mix too, . . . so . . . Thank heavens we are all  a bit different, eh?


    AndyP
Title: Re: EQN build thread
Post by: boji on May 13, 2010, 01:57:41 PM
Not sure if this is any help:

Quote
as soon as either R3 and/or R4 are connected, the sound gets really thin and quiet in a way that makes me think this can't be right. all this without power connected, just using the passive components up to R5 and R7.

Quote
Balanced unbalanced line-in question
« Reply #1 on: August 21, 2006, 11:54:16 am » Quote 

--------------------------------------------------------------------------------
As long as you have it wired like this:

primary + to T
primary - to R
shield/ground to S

inserting a TS jack will automatically pull the primary - to ground, giving you an unbalanced input.  Simple eh?  :cool:
The only problem would be if you had a TRS with nothing wired to the R.  Then youd get the familiar one legged transformer bleed sound (very quiet high freq only).
http://www.groupdiy.com/index.php?topic=17624.msg204996#msg204996 (http://www.groupdiy.com/index.php?topic=17624.msg204996#msg204996)
Title: Re: EQN build thread
Post by: Marcocet on May 18, 2010, 01:57:34 PM
Any word on Ed's output tranny?

Title: Re: EQN build thread
Post by: haima on May 23, 2010, 09:07:34 AM
Marcocet - check this thread (last pages) for updates on the output transformer. i think they are not too far off now :)

http://www.groupdiy.com/index.php?topic=28923 (http://www.groupdiy.com/index.php?topic=28923)

EDIT - i just saw you have posted in that thread ;D... but i guess the link up might be useful to someone else.
Title: Re: EQN build thread
Post by: Marcocet on May 26, 2010, 05:53:25 PM
Okay, I put one of the kits together minus the output transformer and R29 (TBD). I've got two questions:

First off can someone post the wiring schemes for the input and output tx? Or at least give me a clue, I always seem to get lost in TX land.

Secondly I got the AML kit and I can't seem to find the stop pins for the switches. Were they not included or am I just blind? I took one of the whole switches apart accidently while looking. Damn are those things well built.

Thanks so much everyone for the help. I kinda jumped in to the deep end with this project but the build went pretty well so far!

Title: Re: EQN build thread
Post by: Hairball Audio on May 26, 2010, 05:56:35 PM
Any word on Ed's output tranny?

It's looking like I will have them in hand by this Friday (May 28th).

Fingers crossed.

Mike
Title: Re: EQN build thread
Post by: peter purpose on May 27, 2010, 02:04:03 PM
Okay, I put one of the kits together minus the output transformer and R29 (TBD). I've got two questions:

First off can someone post the wiring schemes for the input and output tx? Or at least give me a clue, I always seem to get lost in TX land.

Secondly I got the AML kit and I can't seem to find the stop pins for the switches. Were they not included or am I just blind? I took one of the whole switches apart accidently while looking. Damn are those things well built.

The wiring for the input transformer is on the previous page. Also take 6 (screens) to SCR.
For the output, we'll have to wait for colour confirmation from Ed.

Stop pins for the Grayhills should be in a little plastic bag. They're tiny, so handle with care.
Title: Re: EQN build thread
Post by: Hairball Audio on May 27, 2010, 02:36:59 PM
For the output, we'll have to wait for colour confirmation from Ed.

I just spoke with Ed about this earlier today.  I'll have all the wiring/color info on the 1166 product page later today.

Feel free to link to it or post it here.

Thanks,

Mike
Title: Re: EQN build thread
Post by: Slenderchap on May 27, 2010, 03:29:25 PM
Secondly I got the AML kit and I can't seem to find the stop pins for the switches.

The Grayhill switches come from Grayhill packed in 2 different styles....
...individually packaged in a round plastic container which contains the switch, stop pins and silver label
...bulk packed.... where we have to pack the pins and silver label seperately....

When they are individually packed it is assumed the pins are inside the package.... when bulk packed we put a pair of pins (and silver label) into a small plastic bag and put that in another bag with the switch..... either way they should be there.....

If you still cannot find them you can always just use the leg of a resistor.... push it in the hole and cut it off

Colin
www.audiomaintenance.com
Title: Re: EQN build thread
Post by: Marcocet on May 27, 2010, 05:10:24 PM
Lifesavers. Thanks guys. I don't know how I missed the Input tranny wiring on page 4...

I'm so excited to hear this thing.

-marc alan
Title: Re: EQN build thread
Post by: Brizco on May 31, 2010, 03:59:07 AM
grayhill-newbie asking dumb questions:

- once the pins are attached, how can i take them out again? :) do i have to open the switch?




Title: Re: EQN build thread
Post by: zayance on May 31, 2010, 04:07:48 AM
Quote
Insert Quote
grayhill-newbie asking dumb questions:

- once the pins are attached, how can i take them out again?  do i have to open the switch?





i remember there was a round chromed sticker looking like a washer that was closing the pin holes, so it's still possible to take it out, but the stickers will be less and less efficient, at least on the ones i had.
Title: Re: EQN build thread
Post by: Brizco on May 31, 2010, 07:55:01 AM
Quote
Insert Quote
grayhill-newbie asking dumb questions:

- once the pins are attached, how can i take them out again?  do i have to open the switch?





i remember there was a round chromed sticker looking like a washer that was closing the pin holes, so it's still possible to take it out, but the stickers will be less and less efficient, at least on the ones i had.

hmm, the sticker isnt already attached but the pin is. and it wont come out. :(
Title: Re: EQN build thread
Post by: zayance on May 31, 2010, 08:21:26 AM
Quote
hmm, the sticker isnt already attached but the pin is. and it wont come out.

Did you try turning the knob a little when upside down, i did it like that if i remember and it came a little out, just enough to grab it with a tweezer, and if it's really hard stuck, maybe a small magnet or so can help also???? And i suppose this one is not in the right position?
Title: Re: EQN build thread
Post by: Brizco on May 31, 2010, 10:19:42 AM
Did you try turning the knob a little when upside down, i did it like that if i remember and it came a little out, just enough to grab it with a tweezer, and if it's really hard stuck, maybe a small magnet or so can help also???? And i suppose this one is not in the right position?

ill try it with the magnet, good idea. and yes, you suppose right  8)
Title: Re: EQN build thread
Post by: kazper on May 31, 2010, 02:23:00 PM
Did you try turning the knob a little when upside down, i did it like that if i remember and it came a little out, just enough to grab it with a tweezer, and if it's really hard stuck, maybe a small magnet or so can help also???? And i suppose this one is not in the right position?

ill try it with the magnet, good idea. and yes, you suppose right  8)

Magnet....Thats the only way I've gotten them to come out myself.
Title: Re: EQN build thread
Post by: Marcocet on May 31, 2010, 02:48:48 PM
I had to open the switches up part way, wedge a tiny flathead in there and fiddle around with the pins till enough came out to grab with some needle noses.

It was a whole lot of fun. Got the pins out and the switches work fine though. Next time I wait to put the pins in till I take a good look at the faceplate (yeah, I know)

Title: Re: EQN build thread
Post by: Brizco on June 01, 2010, 12:15:08 PM
finally the pin came out :)

setup for sw6 (example): front view, one pin attached most northern, then turning the switch ccw and then attaching the second pin most southern. am i doin it the correct way?

And where do i get the L-Bracket for the carnhill from?
Title: Re: EQN build thread
Post by: Marcocet on June 01, 2010, 05:35:32 PM
Okay, output iron is in! Now to decipher the dreaded R29. Plus some insight on what the trim pots are / how to properly adjust them would be greatly appreciated. Thanks guys

Title: Re: EQN build thread
Post by: djn111 on June 01, 2010, 06:08:56 PM
Hi,

I can help you out on the trimmer adjustment, the rv4 is the gain trimmer, it is in-between the EQ section and the output amp. RV5 is to adjust the output stage, so that the distortion is symmetrical, you need a scoop to adjust this properly, check the ez1290 build from Madriaanse, in his build pdf is a explanation how to :-)

DJN
Title: Re: EQN build thread
Post by: Marcocet on June 01, 2010, 06:28:18 PM
awesome. Thanks!

-marc alan
Title: Re: EQN build thread
Post by: briomusic on June 01, 2010, 06:33:20 PM
I'll get an abortion of a schematic up...... I've been avoiding it like the plague.

peter, just wondering if you had a chance to draw up a schem? especially everything outside of this:
(http://img.photobucket.com/albums/v426/brio/ppeqnquestion.gif)

I am trying to figure out a way to go into the EQ directly from an EZ1290......
Title: Re: EQN build thread
Post by: peter purpose on June 02, 2010, 03:13:16 AM
Let me wake up and I'll answer what I can.
Title: Re: EQN build thread
Post by: Marcocet on June 03, 2010, 07:00:18 PM
Anyone devise a value for R29 with Ed's tx?

I don't even know where to start trying to figure it out myself. Any leads would be appreciated.

Thanks.

Title: Re: EQN build thread
Post by: edanderson on June 03, 2010, 07:14:19 PM
i think in an earlier post in this thread peter said R29 would be in the 600 to 1.2kohm range.  i'd guess you can safely plug in a 1k for now to get it working.

ed
Title: Re: EQN build thread
Post by: Marcocet on June 03, 2010, 07:53:22 PM
Hey Ed, thanks

Yeah, I was going to just do that to make sure everything's working, but I'm not sure how to determine what the best value would be. Obviously not a hurry of any sort.

Title: Re: EQN build thread
Post by: Brizco on June 13, 2010, 04:30:43 AM
i still dont know how to attach the pins to the grayhills...

setup for sw6 (example): front view, one pin attached most northern, then turning the switch ccw and then attaching the second pin most southern.

is this the correct?
Title: Re: EQN build thread
Post by: peter purpose on June 14, 2010, 06:41:01 AM
i still dont know how to attach the pins to the grayhills...

setup for sw6 (example): front view, one pin attached most northern, then turning the switch ccw and then attaching the second pin most southern.

is this the correct?

Sort of. Have you read the instructions that come with the switch?
I'll stick up a pic of pin positions when my camera is charged.
Title: Re: EQN build thread
Post by: peter purpose on June 14, 2010, 06:53:00 AM

peter, just wondering if you had a chance to draw up a schem? especially everything outside of this:
(http://img.photobucket.com/albums/v426/brio/ppeqnquestion.gif)

I am trying to figure out a way to go into the EQ directly from an EZ1290......

Very rough schem, but should help.

(http://lazpro.com/84rough.jpg)
Title: Re: EQN build thread
Post by: Brizco on June 14, 2010, 10:03:25 AM

Quote

Sort of. Have you read the instructions that come with the switch?
I'll stick up a pic of pin positions when my camera is charged.

i read the datasheet of the rotary switches, but i wasn't lucky finding something. or my english is too bad...

a pic would be very helpful!
thanks a lot!!
Title: Re: EQN build thread
Post by: djn111 on June 14, 2010, 10:25:08 AM
Hi,

About the pin position of the switch take a resistor, and try all holes one by one till you got the action of the switch you need, only twelve holes, so the job is not to time consuming.

DJN

Title: Re: EQN build thread
Post by: Marcocet on June 14, 2010, 04:05:50 PM
Anyone using this with a standard API rack yet? I'm getting +/- 16v into the Lamda DC converter, however I'm getting +6v on every pin on the way out. No power further down the line either. Any ideas? I'm looking at the Lamda docs and I assume these things are bi-directional? It states that the input should be 24v to get +/- 15v output, however the way the circuit is designed we're putting +/- 15 into the input.

Thanks for the help!

EDIT: Swapped out the Lamda. Works great now! Giving a listen as we speak.
Title: Re: EQN build thread
Post by: MM1100 on June 14, 2010, 10:09:55 PM
Marc,

What exactly do you mean by "Swapped out the Lamda." Did you have a faulty Lambda or did you just have it hooked up incorrectly?

Thanks - Nathan - Studio315
 
Title: Re: EQN build thread
Post by: Marcocet on June 14, 2010, 10:14:54 PM
Faulty one I believe. I just swapped it for another and the unit's working fine. However I was doing all this in the back of the studio while another session was going on, so I got to test it only long enough to know that it's working. I'm planning to give it a good listen tomorrow!

-marc alan
Title: Re: EQN build thread
Post by: Brizco on June 15, 2010, 03:55:09 AM
Hi,

About the pin position of the switch take a resistor, and try all holes one by one till you got the action of the switch you need, only twelve holes, so the job is not to time consuming.

DJN



thanks DJN, got that. but i'm still not shure if im doin it correct. the switches have no stop, so first i attach the stop pin... and then do i have to turn CCW or CW before attaching the pin to stop at sixth point?  i mean there are two possibilities, two sides , or am i just confused ???
Title: Re: EQN build thread
Post by: briomusic on June 15, 2010, 05:14:22 AM
you sir, are a gentleman and a scholar  ;D


Very rough schem, but should help.

(http://lazpro.com/84rough.jpg)
Title: Re: EQN build thread
Post by: peter purpose on June 15, 2010, 10:41:28 AM
My camera is bolloxed, so with the switch in anything but position 1..... put a pin in 12 o'clock.
This is the start point fully counter clockwise.
Then depending on how many positions.. i.e. 5... stick the pin in at 5 o'clock.

Making sense?
Title: Re: EQN build thread
Post by: Brizco on June 15, 2010, 12:15:40 PM
My camera is bolloxed, so with the switch in anything but position 1..... put a pin in 12 o'clock.
This is the start point fully counter clockwise.
Then depending on how many positions.. i.e. 5... stick the pin in at 5 o'clock.

Making sense?

thanks peter!! FCCW was the key!
Title: Re: EQN build thread
Post by: funkymonksf on June 24, 2010, 10:00:01 AM
For those not building for a 51x rack what 1mh chokes are you using? If anyone doesn't mind sharing a part number it'd help greatly. Thanks
Title: Re: EQN build thread
Post by: Marcocet on June 24, 2010, 01:00:19 PM
I found it.

I used 22R105C from Mouser (part #580-22R105C). They're way too big and radial but I couldn't find ones nearly small enough or axial to fit on the board. So i crammed these in and they work fine. Hopefully someone else has better advice but these will certainly work in a pinch.

Title: Re: EQN build thread
Post by: peter purpose on June 24, 2010, 01:31:01 PM
I use RS part 191-0712
Epcos Manufacturers Part No. B78108S1105J
Title: Re: EQN build thread
Post by: funkymonksf on June 25, 2010, 11:05:53 AM
Hey Peter would you be willing to share how one might obtain those knobs on the 1084 on the first page? Oh It'd be so sassy to have those....
Title: Re: EQN build thread
Post by: Marcocet on June 26, 2010, 12:00:57 AM
I did the same thing when I saw it. It's a rendering. They don't exist. Yet.

They sure are sexy tho.

Title: Re: EQN build thread
Post by: peter purpose on June 26, 2010, 04:10:14 AM
Those knobs... when eventually manufactured, are to distinguish between the kit and the retail versions.
So please don't ask.
Title: Re: EQN build thread
Post by: haima on June 27, 2010, 07:39:51 AM
i hope the retail units are very popular pete - you deserve it!

maybe us diy'ers should start a list of available knobs that fit - specifically those tiny 1/8" cut/boost knobs....
Title: Re: EQN build thread
Post by: dandeurloo on June 27, 2010, 11:13:05 AM
maybe a group buy on knobs?  Not sure how to do that but if someone finds or makes cool knobs I'm sure a number of people would buy them.  Lets make them a different color then Peters retail version if possible. 
Title: Re: EQN build thread
Post by: jsteiger on June 27, 2010, 11:53:30 AM
I have sent an email to my knob supplier to see if they will do red and blue anodized. They would look similar to Pete's rendering but not exactly the same. The small knob would not have a skirt. The diameter is 3/8" which just makes it inside the indication marks. The larger knobs would have a skirt. I'll see what they say. I would assume either black or clear anodizing would be more cost affordable but I think the red and blue would look killer!

I am building mine with the Lambda V converter so I can plug them to my liking anywhere in my console. I think I am also gonna do my own faceplate so they match the rest of my board.

I working on my Mouser/Digi order now for the parts I need. Will take some time indeed!

best, Jeff
Title: Re: EQN build thread
Post by: funkymonksf on June 27, 2010, 01:15:44 PM
That'd be awesome Jeff. I'm all for it. I've been looking everywhere for some suitable knobs and no luck. I figured if kilo would do custom colors that'd be the best bet, but I doubt they do. Please keep us updated. I'm sure alot of us would be interested.

-Brice Conrad
Title: Re: EQN build thread
Post by: jsteiger on June 27, 2010, 01:49:29 PM
As for the inductors in the US, I have found these at Mouser. http://mouser.com/ProductDetail/Xicon/43LS103/?qs=sGAEpiMZZMsg%252by3WlYCkU6LFPAFG9Gi9baAGxaFiF10%3d (http://mouser.com/ProductDetail/Xicon/43LS103/?qs=sGAEpiMZZMsg%252by3WlYCkU6LFPAFG9Gi9baAGxaFiF10%3d) They are axial, small and inexpensive.

Peter, correct me if I'm wrong, the BOM shows "1MH". According to your RS part, it should be "1mH"? You mean millihenry and not megahenry right? So, the equivalent then is 1000uH or microhenry. All these darned henry's.  ??? Just glad I'm still on a coffee high!  :D

Just trying to help (myself and others!).  ;D

best, Jeff
Title: Re: EQN build thread
Post by: dandeurloo on June 27, 2010, 03:17:52 PM
Jeff, I wondered if you would be able to help with the knobs!
Title: Re: EQN build thread
Post by: haima on June 27, 2010, 08:59:31 PM
jeff's solid aluminium knobs are the best feeling knobs in town  ;D

put me down for two sets, if you manage to er... pull it off.
Title: Re: EQN build thread
Post by: jsteiger on June 28, 2010, 10:50:48 AM
Pardon me if it has been covered 100 times already, in know the pots are 10K linear. I assume that center detent is preferred.
Title: Re: EQN build thread
Post by: haima on June 28, 2010, 11:21:50 AM
hey jeff ol bean:)

bom says:

RV1 10K LINEAR SMALL FORMAT
RV2 10K LINEAR SMALL FORMAT
RV3 50K LINEAR SMALL FORMAT

if the center dent is ACCURATE then it would be handy - but i've heard some (cheaper) center dent pots aren't always dead on - i.e. not always 50% total resistance if you know what i mean... which would be annoying... flat wouldn't be flat.
Title: Re: EQN build thread
Post by: haima on June 28, 2010, 11:28:30 AM
oh, and those cute little pots that peter used on his prototype are Vishay/Sfernice parts - search for PRV6 (and possibly PARV6? too)

mouser and farnell seem to have 'em
Title: Re: EQN build thread
Post by: briomusic on June 28, 2010, 11:41:48 AM
I would hazard a guess that it will be very difficult to fit any other model pot, I tried before and ended up ordering the PRV6's in the end....

Personally I am not too worried about center detent, as each band can be switched off if it isn't used (off position on the freq selector) if you want to have it guaranteed flat.
Title: Re: EQN build thread
Post by: jsteiger on June 28, 2010, 11:49:29 AM
...Personally I am not too worried about center detent, as each band can be switched off if it isn't used (off position on the freq selector) if you want to have it guaranteed flat.
Good point. Time to not over-think things as usual.
Title: Re: EQN build thread
Post by: peter purpose on June 29, 2010, 09:15:31 AM
1000uH 1mH
Title: Re: EQN build thread
Post by: haima on June 29, 2010, 09:28:08 AM
peter, should we be concerned about the current rating of those inductors? how much current gets pulled through them?
Title: Re: EQN build thread
Post by: jsteiger on June 29, 2010, 09:32:09 AM
Good point. The ones I selected and ordered are rated 100mA max. I assumed that would be sufficient but we all not what assume means.
Title: Re: EQN build thread
Post by: haima on June 29, 2010, 09:36:53 AM
peter's suggested part is 130mA...

i have a feeling a neve class A line stage can pull more than 100mA surge at startup? can't remember....
Title: Re: EQN build thread
Post by: jsteiger on June 29, 2010, 10:10:05 AM
peter's suggested part is 130mA...
Yes I did see that.

Quote
i have a feeling a neve class A line stage can pull more than 100mA surge at startup? can't remember....
There was some back and forth banter with Dan K. about this in Peter's original thread. Nothing definite was ever mentioned in public but I think that there is some delay circuitry involved before the DC-DC converter to limit the inrush current. The last mention is here. http://www.groupdiy.com/index.php?topic=36096.msg445440#msg445440 (http://www.groupdiy.com/index.php?topic=36096.msg445440#msg445440)
Title: Re: EQN build thread
Post by: haima on June 29, 2010, 10:55:53 AM
there's also this thread - http://www.groupdiy.com/index.php?topic=28577.40 (http://www.groupdiy.com/index.php?topic=28577.40) - in which dan kennedy gave us the delayed turn on DC-DC converter circuit from his 500 series mic preamp.

dan said:
Quote
"I also used a simple transistor turn-on circuit that keeps the converter off until the rack is near full supply, or it's initial surge will cause the regulators of the rack to current limit."

(http://lazpro.com/dansdc.jpg)

still not sure about the total current drawn though those inductors though. i believe a properly biased 1073 draws around 110mA? this circuit would be slightly less i think?
Title: Re: EQN build thread
Post by: peter purpose on June 29, 2010, 02:17:35 PM
130mA each on two rails.... not had a problem with said part.
Title: Re: EQN build thread
Post by: Marcocet on June 30, 2010, 08:41:45 PM
Does anybody have a good scan of their PCB available? I built all of mine and now am having some difficulty following the traces in order to troubleshoot one of them.

The rest all function perfectly (though I have noticed that there's about a 1db gain loss when they're inline, both while engaged and bypassed) but on one of them the mid band doesn't seem to do anything. I pulled the mid amp card and swapped it as well as checked out all my solder joints and everything looks pretty good, but it's hard to follow exactly where the signal's going without a map and I stupidly didn't keep a photocopy of one of the PCBs around.

Thanks for any help!

-marc alan goodman
Title: Re: EQN build thread
Post by: canidoit on June 30, 2010, 10:23:35 PM
Does anybody have a good scan of their PCB available? I built all of mine and now am having some difficulty following the traces in order to troubleshoot one of them.

The rest all function perfectly (though I have noticed that there's about a 1db gain loss when they're inline, both while engaged and bypassed) but on one of them the mid band doesn't seem to do anything. I pulled the mid amp card and swapped it as well as checked out all my solder joints and everything looks pretty good, but it's hard to follow exactly where the signal's going without a map and I stupidly didn't keep a photocopy of one of the PCBs around.

Thanks for any help!

-marc alan goodman
I have one up here if you need it.
http://www.groupdiy.com/index.php?topic=38884.msg492539#msg492539

Download the links for a larger and high resolution version of what I have so far.
Title: Re: EQN build thread
Post by: Marcocet on June 30, 2010, 10:29:51 PM
Thanks dude!
Title: Re: EQN build thread
Post by: haima on July 01, 2010, 03:48:31 AM
marc - you've finished a few channels? how do you like the sound? i'm pretty close to finishing my pair - just waiting for a few parts to come from the US...
Title: Re: EQN build thread
Post by: peter purpose on July 01, 2010, 08:13:40 AM
I have noticed that there's about a 1db gain loss when they're inline, both while engaged and bypassed

Have you tried adjusting RV4 (fader) to make up the loss?
If you have, then R29 needs to be reduced to increase the gain in the output amp.
Title: Re: EQN build thread
Post by: Marcocet on July 01, 2010, 12:08:04 PM
Ahh. Yeah, I calibrated it, but until just now I didn't know exactly what R29 was responsible for. I just threw a 1k in there. Any suggestions on what range I should jump to?

They sound awesome. I've put one of them up against my 1064s in some quick listening tests and they were almost identical, however I'm doing my first real session with 7 of them in the console today.

Here are some quick phone photos:

(http://strangeweatherbrooklyn.com/sales/EQNdesk1.jpg) (http://strangeweatherbrooklyn.com/sales/EQNdesk2.jpg)
Title: Re: EQN build thread
Post by: zayance on July 01, 2010, 12:11:16 PM
Looks super nice, funny i wanted to use these kilo aluminium knobs also, i had some for one stompbox, and it was looking killer on EQN, very nice  8) :)
Title: Re: EQN build thread
Post by: funkymonksf on July 01, 2010, 12:29:44 PM
Awesome work Marc. I agree that the Kilo knobs look killer. I'm actually surprised how good thy look. Might do it myself.

Does anyone have any tips or instructions on how to bias and setup the 1084?

Has there been any common decision on what value to use for R29? What are you using Peter?

Thanks to you all,
Brice Conrad
Title: Re: EQN build thread
Post by: haima on July 01, 2010, 12:31:55 PM
looks amazing! where's the drool icon?!?

yes, those knobs look great - where did you get them? they'll do - at least until jeff comes though with his red and blue numbers  :)

nice studio too marc, checked out your site...


Title: Re: EQN build thread
Post by: jsteiger on July 01, 2010, 12:50:55 PM
Nice desk Marc. That looks like it is a PW tweener? Between the Saul Walker era 2488's and before Paul started with the Legacy line? The bus modules look familiar. I quoted a guy in SF on making 40 new custom bus modules. He said his were all dead and useless.

Are those 4 band APSI parametrics off on the right?  :o  Nice.

Good to know you are digging the EQN's. After today's UPS, I should have everything on hand to build out my pair. I hope the wife gives me enough space to get that done this weekend!!  :D  I also hope she never reads this post!!  ::)

Best, Jeff
Title: Re: EQN build thread
Post by: zayance on July 01, 2010, 01:06:10 PM
Quote
yes, those knobs look great - where did you get them? they'll do - at least until jeff comes though with his red and blue numbers 

Digikey has all the Kilo knobs catalog, my favorite aluminium knobs  :), the Knurled Straight are not cheap tough
Title: Re: EQN build thread
Post by: haima on July 01, 2010, 07:20:11 PM
Quote
Digikey has all the Kilo knobs catalog, my favorite aluminium knobs  Smiley, the Knurled Straight are not cheap tough

darn. i knew you were gonna say that - i JUST placed my digikey order for the DC-DC converters! and at $30 shipping to australia i won't be doing another one for a bit  :'(

jeff - i believe marc's desk is a 1608!
Title: Re: EQN build thread
Post by: jsteiger on July 01, 2010, 07:27:37 PM
...
jeff - i believe marc's desk is a 1608!
Haha! Right you are! My stare was so focused on the EQN's and then directly to the APSI's...that I never even noticed the meter bridge! Duh!!
Title: Re: EQN build thread
Post by: haima on July 01, 2010, 07:56:57 PM
any movements on the coloured knobs front jeff?  :-*
Title: Re: EQN build thread
Post by: jsteiger on July 01, 2010, 08:17:43 PM
any movements on the coloured knobs front jeff?  :-*
I talked to them yesterday about a big 3-50 pointer knob delivery. She reassured me that the owner had my price request for the EQN and would be handling it himself. I have not heard yet. I will follow up with them again Tuesday. Monday is Independence day here!!  :)
Title: Re: EQN build thread
Post by: zayance on July 01, 2010, 08:27:38 PM
Quote
darn. i knew you were gonna say that - i JUST placed my digikey order for the DC-DC converters! and at $30 shipping to australia i won't be doing another one for a bit 

Sorry about that, but just for info, Digikey has free shippings worlwide for purchase over 65 euros, or dollars don't remember, anyway, those 30 dollars would have been for other things, like knobs yes  :), but dont want to be a PITA just wanted to let you know if you missed that one  ::)
Title: Re: EQN build thread
Post by: Marcocet on July 01, 2010, 08:37:22 PM
Yip. 1608. Yes they're APSI parametrics. I have a pair of the 559 Graphic modules too in a rack off to the side, as well as 4 Aengus EQs which are my favorite things in the friggin universe.

As of a few weeks from now the desk will be 16 EQN - 8 APSI 562 - 16 Purple ODD. Extremely excited

Anyway did my first session with them today. Ended up using them on almost everything. If I was eqing on the way in I used the 1064s, but I didn't bother patching them in at all during the mix. EQNs were killing it.




Onward: I haven't had a lot of time but I've been trying to figure out what could be wrong with my 8th module. If the mid band is off it passes signal perfectly, but if I turn it to any of the settings i lose my signal. I checked all my solder points and tried to trace the lines out but I can't quite figure why I would be losing all of them except for off. If anybody has any clues it would be greatly appreciated.

Title: Re: EQN build thread
Post by: haima on July 01, 2010, 08:39:45 PM
Quote
Sorry about that, but just for info, Digikey has free shippings worlwide for purchase over 65 euros, or dollars don't remember, anyway, those 30 dollars would have been for other things, like knobs yes  Smiley, but dont want to be a PITA just wanted to let you know if you missed that one

thanks zayance - but it must be worldwide except for australia!... i ordered a lot more than 65 euros - i believe it's always a flat fee of $30usd for australia

mouser on the otherhand is free shipping on orders over $200 aud - very handy!
Title: Re: EQN build thread
Post by: zayance on July 01, 2010, 08:45:25 PM
Oh yes you're right i've just checked, when you change country to Australia you have one blinking message telling that, that's a real PITA.
Title: Re: EQN build thread
Post by: haima on July 01, 2010, 09:26:35 PM
Quote
Onward: I haven't had a lot of time but I've been trying to figure out what could be wrong with my 8th module. If the mid band is off it passes signal perfectly, but if I turn it to any of the settings i lose my signal. I checked all my solder points and tried to trace the lines out but I can't quite figure why I would be losing all of them except for off. If anybody has any clues it would be greatly appreciated.

marc - do you have a card edge "harness" - like an external 500 series connector wired to XLRS and power - for the bench?

if you have one of those and a signal tracing probe/scope you should be able to follow the signal through the mid section and find out where it stops.

it's probably nothing too big, if it passes signal in the OFF position it would seem that it's something in the "BA211/A" section of the schem pete posted a few pages back. look for solder bridges, wrong parts etc around the midrange inductor, switch and caps? i would expect something there is shorting all your signal to ground perhaps?
Title: Re: EQN build thread
Post by: Marcocet on July 02, 2010, 01:19:00 AM
Yip, that's been my guess. I do have a test rig set up and an oscilloscope. However I'm pretty new to the whole thing and haven't been able to find the trouble spot yet. I have learned that if i swap out the mid amp card the problem stays the same. I'm gonna have to spend some time figuring out how to track down the signal tomorrow. I'll let you know how it goes. Thanks!

Title: Re: EQN build thread
Post by: MM1100 on July 02, 2010, 03:05:19 AM
Nice job Peter! After several hours of work we have a beautiful sounding EQ. Don't laugh at the knobs ladies, they are only temporary. No issues.
Title: Re: EQN build thread
Post by: Brizco on July 02, 2010, 08:20:35 AM
Thanks Peter! Finished mine yesterday...

(http://img171.imageshack.us/img171/6204/eqn.jpg)
Title: Re: EQN build thread
Post by: haima on July 02, 2010, 08:36:19 AM
Quote
I have learned that if i swap out the mid amp card the problem stays the same. I'm gonna have to spend some time figuring out how to track down the signal tomorrow. I'll let you know how it goes. Thanks!

yes, according to pete's schem the signal always goes through that amp card, so it appears that part is fine. good luck tracing it - mine isn't done yet otherwise i'd be able to give you more specific places to probe...

BTW: looking good Brizco & MM1100!
Title: Re: EQN build thread
Post by: peter purpose on July 02, 2010, 08:44:28 AM
And the pix start flowing in.... keep em coming.

Marc... Could you have the switch stop pins in the wrong place on the dodgy 8th?
Just a guess, as signal would go nowhere if you're the wrong side of the pins.

As for R29... stick 750R in there and adjust with the fader.
I haven't built any yet, so can't report.
Title: Re: EQN build thread
Post by: funkymonksf on July 02, 2010, 05:30:27 PM
How is the input transformer being mounted on the PCB? Are you guys using an L shaped bracket or this something included in the kit that I'm missing. Just want to have all bases covered before I send out my mouser/digikey order.  Also, Marcocet would you mind sharing what size knobs you got? I think I'm going to follow the KILO route. It looks really good. I'd do it myself I just don't know the diameter size for the front panel markings.

The builds look great!

Thanks,
Brice Conrad
Title: Re: EQN build thread
Post by: Marcocet on July 02, 2010, 05:48:07 PM
I can't remember exactly what the diameters were but they were easily measured with a ruler and the faceplate. 1/4" shafts on the switches and 1/8" on the pots.

As far as mounting the transformer I used 1" 4-40 screws and nuts. My local store didn't have washers that size but they're holding fine without them. I don't plan on moving the things around much.



As far as the stop pins I checked them and they're right, plus it's the 12 position switch so even if I was on the opposite side at least some of the settings would work. Gotta be something in the signal path that involved all of the on positions but not the off, I'm just having trouble sorting out exactly what those spots are. However I know I can get through it, just gotta keep looking at the schematics and layouts till my brain jumps into the right tracks.

Title: Re: EQN build thread
Post by: haima on July 02, 2010, 06:55:32 PM
check out around those 4m7 resistors on the underside of the mid switch too - maybe there's a solder bridge or something amiss there?
Title: Re: EQN build thread
Post by: crisotop on July 22, 2010, 07:08:00 AM
Would 1/8W be fine for the 4M7 mini resistors as well?

thanks,
Christoph
Title: Re: EQN build thread
Post by: briomusic on July 22, 2010, 08:15:38 AM
Would 1/8W be fine for the 4M7 mini resistors as well?

thanks,
Christoph

yes, I think only 1/8 Watt is available in the required size which is 204 (the normal 207 resistors won't fit!)
Title: Re: EQN build thread
Post by: ultra-alex on August 04, 2010, 12:30:53 PM
finished mine today.  :D
altough i went through some trouble with one of the amp boards, but all working fine now. thanks, peter!
cheers, alex

(http://www.ultraton.net/33609diy/EQN_fin1_640.jpg)
Title: Re: EQN build thread
Post by: dmp on August 09, 2010, 12:50:05 PM
I'm looking for the ceramic caps and wondering if others have found these in the USA (mouser, newark...)
I can't find a few in the 5mm LS, and the .1uf in COG.   

CAPACITOR          Order #
10uf / 25v tant   74-199D25V10-E (mouser)
22uf / 25v tant   74-199D16V22-E3
10pf COG 2.5mm   140-500N2-100J-RC
180pf COG 5mm   140-50N5-181J-TB-RC
220p COG 2.5mm   66C6064 (newark)
330p COG 2.5mm   66C6073
470 pf cog 5mm   66C6083
100nf COG 5mm   

Title: Re: EQN build thread
Post by: zayance on August 09, 2010, 12:57:16 PM
I found them all at Digikey IIRC, they were Murata brand, with the right pitch and all, try again, be precise  ;), you know what, give me a minute i'll give you the ref of Digikey.

22uf / 25v tant : 478-4175-ND
10uf / 25v tant : 399-3640-ND
10pf COG 2.5mm : 490-3678-ND
180pf COG 5mm: 490-3695-ND, i just bend them to go to 5mm, same same
220p COG 2.5mm : 490-3638-ND
330p COG 2.5mm : 490-3723-ND
470 pf cog 5mm : 490-3738-ND
100nf COG 5mm : 445-4756-ND

Check if i'm correct again, maybe i did some typing mistakes who knows, and maybe there are some cheaper alternatives, but i was doing some order there so, and a little spare is always ok, will find it's need in other projects as well  ;)





Title: Re: EQN build thread
Post by: dmp on August 09, 2010, 01:08:15 PM
Ok, thanks! I found them right away on digikey (it's nice that they include LS in the search filter, which mouser does not!).
Title: Re: EQN build thread
Post by: zayance on August 09, 2010, 01:09:59 PM
Anyway i gave you the links in case of, look up.
Title: Re: EQN build thread
Post by: dmp on August 09, 2010, 02:19:00 PM
Thanks Zayance!
That 100nf is a pricey cap...
Title: Re: EQN build thread
Post by: zayance on August 09, 2010, 02:29:38 PM
yep  ::), if you get cheaper somewhere else, please share  :)
Title: Re: EQN build thread
Post by: edanderson on August 09, 2010, 10:50:34 PM
100nf (or 0.1uf as it is more often written here in the states) is at the "large" end of the range for ceramic caps, and will generally be expensive in c0g.  you could definitely substitute a 0.1uf film capacitor in 5mm lead spacing.  panasonic ECQ-V series stacked polyester is a "jellybean" part - i keep a bag of 100 in my desk.  part P4725-ND, about 10 cents each.  wima, AVX, epcos all make box style caps in 5mm pitch that would also work.

ed
Title: Re: EQN build thread
Post by: zayance on August 10, 2010, 03:50:47 AM
Thanks a lot for the tip, yes i have those ECQ series, in a lot of different values actually, thanks for sharing.
Title: Re: EQN build thread
Post by: dmp on August 17, 2010, 09:36:07 PM
Looks like that 0.1uf cap is just for decoupling the V+ of the two small amp boards, so it certainly does not need to be high end.
Peter, I got my kits - they look great. Thanks much for putting this together!
Title: Re: EQN build thread
Post by: dmp on August 17, 2010, 09:40:45 PM
Any idea when the Ed Anderson input transformer will be ready?
Title: Re: EQN build thread
Post by: dandeurloo on August 21, 2010, 10:20:59 PM
R17 2k7/6k8 -again how do I determine the correct value?
Different schematics have different values. This is the q setting resistor for the mid inductor. I used 6k8.

Hey Peter if I use something in the middle like 5.1k will that be a wider q or sharper q then 6.8k?
Title: Re: EQN build thread
Post by: peter purpose on August 22, 2010, 11:35:00 AM
Sharperer.
Title: Re: EQN build thread
Post by: Hairball Audio on August 22, 2010, 11:50:00 AM
Any idea when the Ed Anderson input transformer will be ready?

4-6 weeks would be my guess.  There are always a lot of slow downs and hold ups in the first batch.  It's all necessary to get it right!

Outputs should be back in stock in a week.

If you have any follow-up Q's please use my WM thread.

Thank guys!

Mike
Title: Re: EQN build thread
Post by: dandeurloo on August 22, 2010, 08:56:54 PM
I'm getting close on the EQ's!  I have a few noobish questions I thought I would check in on with you guys before I solder these last few pieces in. 

1. what cap are you guys using for C50?  I have the AML kit and the WIMA cap that came with it is to wide to fit in between TR1 & TR2.  I can get the leads to reach but it doesn't sit well and it is touching everything around it.  Is there and skinny cap that can fit in there? 

2. I also am not sure what value u1K63 wima caps are?  Is that the cap for C31? 

3. I know it was briefly discussed, but how do we mount the input TX?  Do we take out two of the screws that are holding the TX together and put longer ones in and screw those through the PCB into the TX?  Or is there an different method.

4.  On the PCB next to the input TX, where it say OUT +- and in between the IN+- and the SCR there are lines.  Are we suppose to jumper those and connect the input TX to oneside of those?

Thanks for the help.
Title: Re: EQN build thread
Post by: peter purpose on August 22, 2010, 09:11:51 PM
1. Stick it on the underside.
2. Hunh?
3. Yes.
4. No... they're extra holes for Ed's tx.
Title: Re: EQN build thread
Post by: dmp on August 22, 2010, 10:19:01 PM
Quote
u1K63 wima caps

0.1uf C17, C18, C31
Quote
cap are you guys using for C50?

You also could order a 2.5mm thick cap, like 505-MKP24700/630/5 (mouser)


 
Title: Re: EQN build thread
Post by: dandeurloo on August 22, 2010, 10:26:11 PM
dmp and Peter thanks.  This helps me sort out a few things.  I was starting to think I had some caps in the wrong spot but I think I got them right.  I'm getting much closer. :)

I think I will mount these 4n7 film on the underside and see how that works. 

I'm gonna have to decide on Knobs soon.  Maybe the KILO's or if Jeff has knobs coming through soon I will be set.
Title: Re: EQN build thread
Post by: funkymonksf on August 23, 2010, 06:19:23 PM
Can someone explain what CW W CCW means for the smaller potentiometer wiring? I am assuming it means clockwise w? counter clock wise, but how do I know what is what on the PRV6?  Can anyone explain in detail. Sorry this may be the dimmest of questions yet, but here it is.... and thanks

-Brice Conrad

P.s.
Peter the kit looks great! So very excited
Title: Re: EQN build thread
Post by: kazper on August 23, 2010, 06:40:31 PM
Can someone explain what CW W CCW means for the smaller potentiometer wiring? I am assuming it means clockwise w? counter clock wise, but how do I know what is what on the PRV6?


W= wiper and you have Counter Clockwise and Clockwise correct. Basically Peter is trying to help you not make a wiring mistake.
RV1,RV2,RV3 you should be concerned with the others are just trim pots

(http://lazpro.com/xinf.jpg)
Title: Re: EQN build thread
Post by: dmp on August 23, 2010, 06:55:52 PM
I think that would mean with the pot turned fully cw, the cw tab is the one with zero resistance to wiper
You can use a ohm meter to figure out which one the wiper is.
As long as you get the wiper right, worst case the knob will work backwards and then you'd have to flip the cw and ccw wires
More detail:  http://en.wikipedia.org/wiki/Potentiometer
Title: Re: EQN build thread
Post by: dandeurloo on August 23, 2010, 07:43:14 PM
isn't the wiper always in the middle? so thats easy to find.
Title: Re: EQN build thread
Post by: dmp on August 24, 2010, 11:24:03 AM
Quote
R17 2k7/6k8 -again how do I determine the correct value?
From the schematics it looks like the 1073 used 2.7k for R17, and 1084 used 6.8k.
If I understand it correctly, the Hi-Q switch is putting R19 in parallel with the R17.
If you want both the 1073 and 1084 options, use 6.8k for R17, then choose R19 such that you get R19||6.8k=2.7k when you flip the Hi-Q switch.
That value would be 4.5k for R19.
Title: Re: EQN build thread
Post by: briomusic on August 25, 2010, 04:52:56 AM
thanks dmp, for xplainin how this q thang works!  :D
Title: Re: EQN build thread
Post by: loopermc5 on September 01, 2010, 09:35:22 PM
Thanks for this project Peter......Got mine up and running post some pics once I get knobage. So is the bias setup the same as the pre's ?

Thanks

P.s I got alpha pc mount 1/4 shaft to fit great just used a file to angle the solder pcb's some,if your looking to save some bucks. I can post pics if anyone wants to see.
Title: Re: EQN build thread
Post by: peter purpose on September 02, 2010, 09:25:06 AM
So is the bias setup the same as the pre's ?

Exactly
Title: Re: EQN build thread
Post by: dandeurloo on September 04, 2010, 10:46:09 PM
RV4/5 -what is the alignment procedure for these trimmers? is it similar to the 'symmectrical clipping' process on the 1290 preamp?
Exactly.

Ok, i looked at the 1290 thread.  I still am a little un clear on how to do this. 

1. Do we need to adjust just RV5 or both RV4 and RV5?

2. I don't have a scope but maybe able to go to a friend who has one.  Do I want it to hard clip or just clip?  Not sure what to look for.

3. Is there anyway to do this without a scope? 

Thanks
Title: Re: EQN build thread
Post by: briomusic on September 04, 2010, 11:23:32 PM
RV4/5 -what is the alignment procedure for these trimmers? is it similar to the 'symmectrical clipping' process on the 1290 preamp?
Exactly.

Ok, i looked at the 1290 thread.  I still am a little un clear on how to do this. 

1. Do we need to adjust just RV5 or both RV4 and RV5?

RV5 is the clip adjust. RV4 is to adjust level difference of 'eq in' vs 'eq out'. adjust RV4 with all the frequencies set to "off" to get the same level at both positions of the 'eq in' switch.

2. I don't have a scope but maybe able to go to a friend who has one.  Do I want it to hard clip or just clip?  Not sure what to look for.

"Just clip" is best. you are basically trying to find out if the top or bottom half of the sine waves clips first. if you hard clip it will look like they both clip all the time. it just needs a bit of tinkering with the amount of level you send into the eq and the setting of RV5. when the onset of clipping is happening at both the top and bottom half of the sine wave you have the correct bias.

3. Is there anyway to do this without a scope? 

yes, you can do it with the waveform display of your DAW but it takes a little longer (make adjustment/record audio/zoom in to waveform/make another adjustment/record again/etc)

Title: Re: EQN build thread
Post by: dandeurloo on September 05, 2010, 06:55:45 PM
The wiring for the input transformer is on the previous page. Also take 6 (screens) to SCR.
For the output, we'll have to wait for colour confirmation from Ed.

I've got a number of minor issues with my EQ's.  I tried biasing the eq's and found this so far.

1. I have a much lower output then going into the eq.  Could it be that I don't have anything hooked up to the SCR pad on the input transformer?  I saw the earlier hook up diagram and just saw this.  Does pin 6 go to SCR?

2. My gain pots are wired backwards.  Easy Fix.

3.  So far I noticed that my LF switch is a little wierd.  "Off" is in the second position and I have sound coming out of the 1st position?  Is that something to do with the stopper pins in the grayhill or something else.


Title: Re: EQN build thread
Post by: dandeurloo on September 05, 2010, 08:13:14 PM
I wired pin 6 of the input tranny to SCR. 

I fixed the backwards wired gain pots. 

But now I have random scratchy sounds out of both eq's and at least -20db signal lose. 

I am also pretty sure my stop pins are all in wrong positions of the grayhill's because it doesn't seem to be working properly.

Any ideas on how to trouble shot this. 

Title: Re: EQN build thread
Post by: haima on September 05, 2010, 09:05:45 PM
you can remove the switch pins from the front using a strong magnet i imagine...

i've got photos of where the switch pins need to go - i'll post them asap in case you need help.

Title: Re: EQN build thread
Post by: dandeurloo on September 05, 2010, 09:41:24 PM
Thank you! That would help a ton.

I'm going through part by part now to check again for errors as well.  

would it matter if I have R1 and R2 installed even though I'm using it with 51x?  I did it before I saw they aren't needed and I checked the Schemo and didn't see them on it.  So I figured it would be completely by passed so it wouldn't hurt to leave them in.  Am I correct in my thinking?
Title: Re: EQN build thread
Post by: dandeurloo on September 05, 2010, 10:21:22 PM
I just cross checked all the resistors and the COG's and tant's and electrolytic.  All good!

It must be the switch pins in the wrong spot or some how I messed up the WIMA's?  

I don't have anything in J1.  Does that need anything?

I'm using 750R in R29 as well.
Title: Re: EQN build thread
Post by: loopermc5 on September 06, 2010, 12:35:54 AM
I just cross checked all the resistors and the COG's and tant's and electrolytic.  All good!

It must be the switch pins in the wrong spot or some how I messed up the WIMA's? 

I don't have anything in J1.  Does that need anything?

I'm using 750R in R29 as well.
i think your right to check your pins I bet it solves it. MY first one worked perfect then somehow the second one got all messed up must have been up to late anyways it did all sorts of foolishness till i fixed it.My pins were right but the switch shaft was turned to the wrong side when I place them.
Title: Re: EQN build thread
Post by: dandeurloo on September 06, 2010, 01:13:57 AM
I think that will fix it.  I just need to figure out the proper place for the pins.  I have been doing this stuff late at night so I'm sure it was my fault.
Title: Re: EQN build thread
Post by: crisotop on September 06, 2010, 07:15:45 AM
Anyone found suitable pots with center click in europe? I was browsing Farnell and RS (and the smaller shops ones like Banzai and Musikding) but found nothing that would fit (nor the recommended Vishays)? Any links would be very handy..

Thanks!
Christoph
Title: Re: EQN build thread
Post by: peter purpose on September 06, 2010, 12:39:59 PM
Punch prv6 into Farnell
Title: Re: EQN build thread
Post by: crisotop on September 06, 2010, 12:44:18 PM
thanks peter, already looked at them - but as far as I've understood they have no center click?

cheers again,
Christoph
Title: Re: EQN build thread
Post by: peter purpose on September 06, 2010, 01:02:20 PM
What do you need a click for....... is this a brail eq?
Title: Re: EQN build thread
Post by: dandeurloo on September 06, 2010, 01:11:32 PM
Hey peter can you give me some help figuring out the stop pins on the grayhills?  I think they are all messed up.

Also, I used Clarostat 308 pots.  That portion works great.
Title: Re: EQN build thread
Post by: peter purpose on September 06, 2010, 02:02:30 PM
Page 6
Title: Re: EQN build thread
Post by: briomusic on September 06, 2010, 02:11:11 PM
What do you need a click for....... is this a brail eq?
I agree with this, given the common pot tolerances you're more likely not to be at +-0dB on your centre click anyway. better and easier to switch the band off with the frequency selector if it is unused.
Title: Re: EQN build thread
Post by: dandeurloo on September 06, 2010, 03:25:22 PM
Peter, is this right for the switches?

I stuck resistor leads in to show the placements.

This is for the top 2 switches.

(http://www.dandeurloo.com/diy/LAZ%20EQN/top%202%20switches.jpg)

And this for the bottom 2 switches.


(http://www.dandeurloo.com/diy/LAZ%20EQN/bottom_switches.jpg)
Title: Re: EQN build thread
Post by: peter purpose on September 06, 2010, 03:43:11 PM
Peter, is this right for the switches?


No.
Title: Re: EQN build thread
Post by: dandeurloo on September 06, 2010, 03:49:38 PM
Ok, it makes sense because it doesn't work.  Haha.  At least I can narrow it down to the switches hopefully then.

I love your answers.  hahaha

Any help?

Title: Re: EQN build thread
Post by: peter purpose on September 06, 2010, 03:52:20 PM
Dan, read the instructions that come with the switches... Then go to page 6.
Title: Re: EQN build thread
Post by: dandeurloo on September 06, 2010, 03:57:21 PM
Sorry the instruction got thrown out in a frantic house cleaning by the wife.  I looked on grayhill's site but couldn't find a digital print of them.  Anyone have a link?

I have read page 6 a number of times, still trying to sort it out.

thanks
Title: Re: EQN build thread
Post by: 12volts on September 06, 2010, 04:36:05 PM
Peter, is this right for the switches?

I stuck resistor leads in to show the placements.

This is for the top 2 switches.

(http://www.dandeurloo.com/diy/LAZ%20EQN/top%202%20switches.jpg)


Dan, summat else.

On top of your pin location problems ...... If you look on the photo, you haven't filed down the PCB
'pips' left over from routing. The metalwork sits flush on this edge. The 'pips' have to be removed before
assembly .......



Frank
Title: Re: EQN build thread
Post by: peter purpose on September 06, 2010, 04:52:05 PM
Frank... he's obviously a muso in a hurry.
Title: Re: EQN build thread
Post by: 12volts on September 06, 2010, 05:01:40 PM
Frank... he's obviously a muso in a hurry.


I have a soft spot for musos. Because of them I drink.

Frank
Title: Re: EQN build thread
Post by: peter purpose on September 06, 2010, 05:28:11 PM
Frank.... That's why I got out of the studio business.... I still drink though..!!
Title: Re: EQN build thread
Post by: dandeurloo on September 06, 2010, 06:46:38 PM
Thanks for the compliments guys.  I do make my living from making music and working with musicians... not circuits as I am sure you can tell.    Because of that I do have plans for this wonderful project as soon as I can get it wrapped up. 

Frank I do have plans for a little file time once I go to the shop again.  Sharpe eye!

Title: Re: EQN build thread
Post by: peter purpose on September 06, 2010, 07:32:40 PM
Dan... don't try to seduce Frank to into giving you the answer you lazy twunt.... read something.!!
Title: Re: EQN build thread
Post by: dandeurloo on September 06, 2010, 07:33:46 PM
Wow Peter...
Title: Re: EQN build thread
Post by: zayance on September 06, 2010, 07:35:00 PM
Sorry Mr Peter for helping out  ;D Here is the instructions for the Grayhill if you still need it. And IIRC, when watching the switch from the front with pins flat on the desk, you have to put a pin at 12o' clock, and one at 6 if you want it to switch 6 position etc...Seeing your pictures you just got the switch at 90°, if you check at the back you'll see the numbers according to the positions. Correct me if i'm wrong. And just have to make sure the point 1 of the instructions, if this can help?
(http://img842.imageshack.us/img842/5091/grayhill2.jpg)



Title: Re: EQN build thread
Post by: dandeurloo on September 06, 2010, 07:42:20 PM
Thank you good Sir!
Title: Re: EQN build thread
Post by: dandeurloo on September 07, 2010, 11:30:05 AM
I am 99% sure I got the switches correct thanks to some info from zayance!  So, if anyone else gets hung up on the same thing I did here are a few things.

1. 12:00 on the switches is with the eq laying down pins against your work surface.  Not in the standing up position that it will be in the 500 rack.

2. With this as your starting point the info on page 6 makes sense!

3.  The other thing I kept getting hung up on was the orientation of the flat portion of the shaft.   In this application it doesn't matter other then in making sure you have it start opposite position 2 on the switch.  I was thinking that the screw of the knob would screw into this portion of the shaft like they generally do, but that is not the case!  Just get the positions to work correctly then line up the knob so it points properly on the faceplate.  Not the flat part of the shaft.

Hopefully that info will help anyone else from getting hung up on the switches. 



Title: Re: EQN build thread
Post by: technut on September 08, 2010, 07:16:46 PM
Been Stuck for a couple of days. Fired it up. Power seems to be getting where it needs to and measures correctly but i'm not passing any signal with the eq in or out. Can someone give me a clue on where to start on this. I have resoldered every point on the board.
Title: Re: EQN build thread
Post by: dandeurloo on September 08, 2010, 10:27:39 PM
got any pics?  Is the output tranny wired correctly?

http://www.groupdiy.com/index.php?topic=38884.0


Title: Re: EQN build thread
Post by: technut on September 08, 2010, 10:42:51 PM
I will check again tomorrow but I'm almost 100% sure it is.
Title: Re: EQN build thread
Post by: briomusic on September 09, 2010, 04:36:17 AM
@technut: have you tried toneprobing or scoping around the circuit to see how far the signal gets?

in my case it was 'broken' right at the input transformer and the source (dodgily balanced output of behringer headphone amp) ended up being at fault.

good testing points are R7 (right before the eq section) and C48 (right before the output amp).
Title: Re: EQN build thread
Post by: peter purpose on September 09, 2010, 09:00:08 AM
Any overnight joy technut?
Title: Re: EQN build thread
Post by: technut on September 09, 2010, 10:40:59 AM
Just got to work. Output transformer is wired correctly. Will probe during lunchbreak.
Title: Re: EQN build thread
Post by: technut on September 09, 2010, 04:46:57 PM
Ok i tested at r7 and c48. both are very faint but the same level at both. Maybe its the input tx. I have the right wires connected to the proper places on the pcb. Maybe i dont have the right stuff strapped together on it. Heres how I have it wired. 2 to 4,3 to 5,3 to 4,7 to 8 and 9 to 10.
Title: Re: EQN build thread
Post by: peter purpose on September 09, 2010, 06:45:29 PM
OOOO NO...... !!
Have another look at that schem..... 3-4 as a starting point.

(http://lazpro.com/itx.jpg)
Title: Re: EQN build thread
Post by: technut on September 09, 2010, 06:50:05 PM
Ok I will. Thanks Peter!
Title: Re: EQN build thread
Post by: technut on September 09, 2010, 09:32:21 PM
All fixed!!!!! Just need to calibrate. Thanks again!
Title: Re: EQN build thread
Post by: dandeurloo on September 10, 2010, 06:06:07 PM
Just tested my eq's.  One of them is perfect and sounds amazing! Seriously amazing sounding eq!

The other one has 5db less output.  I went back through and double check all the resistors and everything is right.  I put the other boards op amp card in to this eq and it was the same so its not the op amp cards.  Any suggestions on how to locate the problem?

Thanks
Title: Re: EQN build thread
Post by: zayance on September 10, 2010, 06:20:05 PM
Quote
RV4 is to adjust level difference of 'eq in' vs 'eq out'. adjust RV4 with all the frequencies set to "off" to get the same level at both positions of the 'eq in' switch.

Tried this?
Title: Re: EQN build thread
Post by: dandeurloo on September 10, 2010, 06:21:39 PM
yeah, it doesn't have enough range to make up the 5 db difference. 

I got the other eq with in .5db so that one is good.  And it sounds really really good!
Title: Re: EQN build thread
Post by: zayance on September 10, 2010, 06:27:04 PM
Quote
Quote from: Marcocet on June 30, 2010, 08:41:45 pm
I have noticed that there's about a 1db gain loss when they're inline, both while engaged and bypassed

Have you tried adjusting RV4 (fader) to make up the loss?
If you have, then R29 needs to be reduced to increase the gain in the output amp.

Title: Re: EQN build thread
Post by: dandeurloo on September 10, 2010, 06:47:02 PM
right.  

The thing is, I have 2 eq's built with the same parts.  One is working properly with a .5 db difference with the eq in vs. out.  

The second eq is 5 db difference.  I have a 750R in r29 of both eq's.  All 1% resistors except the 1/2 and 2 watt 12r.  Shouldn't they be a lot closer?  I could change r29 in the second one to a lower value like 600r.  But I would think they would be closer in general.  Makes me think something might be off some where.

If I did change r29 in the second eq would it on change the output level of the eq when it is "in" only.  If so that may be the solution if I can't seem to track down why it wouldn't be closer to the first eq. 


Thanks
Title: Re: EQN build thread
Post by: peter purpose on September 10, 2010, 07:44:58 PM
No... It's not a matching question, but an inadvertant mistake.... sleep on it.
Title: Re: EQN build thread
Post by: dandeurloo on September 10, 2010, 10:38:43 PM
Ok, I glad you have a hunch!  I'll keep poking at it and see if I can find it.

I'm trying to understand the schematic a little better.  Am I correct thinking that the green line is the path if the eq is not switched in?   And the path with out any of the bands switched in but the "EQ IN" goes through R52 (10k) on the schematic?

I'm trying to find what is in the signal path once the EQ switch is IN.

Thanks
Title: Re: EQN build thread
Post by: briomusic on September 11, 2010, 12:15:47 AM
In the schematic all the colored lines are voltages, green being 0Volt. The audio path is the black line coming out of the bottom of the input transformer. Tracing this will eventually lead you to the eq in/out switch :)
Title: Re: EQN build thread
Post by: peter purpose on September 11, 2010, 05:11:10 AM
No... It's not a matching question, but an inadvertant mistake.... sleep on it.

I was very drunk..... and still have no answer.
Title: Re: EQN build thread
Post by: briomusic on September 11, 2010, 05:32:00 AM
my guess is transformer wiring (for the 5dB loss)
Title: Re: EQN build thread
Post by: dandeurloo on September 11, 2010, 12:34:23 PM
i've checked the tranny's about 8 times thinking the same thing.  It is correct.  I wonder if I should re flow the board? 

Could the difference be in the inductors?   

Any good test points?

Title: Re: EQN build thread
Post by: shabtek on September 11, 2010, 12:37:42 PM
could the leads be wrong color?


also, is the hole too tight for Eds xfmr?
Title: Re: EQN build thread
Post by: dandeurloo on September 11, 2010, 12:41:04 PM
In the schematic all the colored lines are voltages, green being 0Volt. The audio path is the black line coming out of the bottom of the input transformer. Tracing this will eventually lead you to the eq in/out switch :)

Ok, clearly a noob question.  The eq "in/out" switch is right after R73 on the schematic correct.  So the problem I should be after that switch since the level is fine when the unit is not engaged.

Its even a little more confusing for me since the shematic numbers don't match the boards but should be able to get it if I can start circling the area a little.

Thanks
Title: Re: EQN build thread
Post by: dandeurloo on September 11, 2010, 12:41:56 PM
could the leads be wrong color?


also, is the hole too tight for Eds xfmr?

Well, I guess they could be but my other eq turned out fine.

The leads fit nicely.

Thanks for suggestion!

Title: Re: EQN build thread
Post by: briomusic on September 11, 2010, 01:29:26 PM
dan, just to clarify, you get the 5dB level difference with:
1) eqn in the signal path, eq switch on 'out'
2) eqn in the signal path, eq switch on 'in', all frequencies set to off.
3) both

IIRC RV4 is active even in "soft bypass" which is what the eq in/out switch is. the signal still goes through all the transformers and the out-amp.

Can you toneprobe/scope a bit and find out if the level difference occurs at R7 or C48? (I guess you would have to check on both the good and the bad unit)
Title: Re: EQN build thread
Post by: dandeurloo on September 11, 2010, 11:02:42 PM
dan, just to clarify, you get the 5dB level difference with:

2) eqn in the signal path, eq switch on 'in', all frequencies set to off.

Can you toneprobe/scope a bit and find out if the level difference occurs at R7 or C48? (I guess you would have to check on both the good and the bad unit)

The second one is what is happening.

Not sure how to toneprobe?  I'll goggle it and see.



Thanks
Title: Re: EQN build thread
Post by: zayance on September 12, 2010, 04:09:12 AM
Quote
Not sure how to toneprobe?  I'll goggle it and see.

Toneprobing, means send a tone for example a sine wave at 1Khz, and use an oscilloscope to find that signal in the circuit with the "probes" of the Oscillo.
Title: Re: EQN build thread
Post by: briomusic on September 12, 2010, 04:21:31 AM
If you don't have access to an oscilloscope you can just use any active speaker (I use a guitar practice amp). Connect the grounds together and put a 1uF (or similar value) polyester cap in series with the input to protect against accidentally hitting DC. now you can poke around your circuit and see what your signal is getting up to on its way. where it gets louder/quiter or lost altogether.
Title: Re: EQN build thread
Post by: haima on September 12, 2010, 04:27:05 AM
** EDIT - oops, briomusic beat me to it  ;D

OR if you don't have a scope you can try using a little amp & speaker to follow the test tone though the circuit.

you'll need a capacitor in series with the probe to block DC. you can even make a probe out of axial capacitor, some heatshrink and some shielded cable, using the cap lead as the probe. just make sure the cap and the cable are rated for the power supply voltage you are working with - 63v is plenty for most solid state stuff, but you might need 500v+ for some valve/tube circuits. terminate the shield at the amp end and just cut it off an insulate it at the probe end.

you'll also need an alligator clip to tie the ground of the amp to the gear you are testing.

there's some good diagrams/pictures around on the net - google "audio probe" or debugging effects pedals etc...

http://www.diystompboxes.com/pedals/debug.html (http://www.diystompboxes.com/pedals/debug.html) etc

it's a good tool to have, even if you have a scope too - sometimes your ears will tell you things you can't see, and vice versa.
Title: Re: EQN build thread
Post by: Holger on September 12, 2010, 12:18:39 PM
Gents, my amp stage doesn't work. I am seeing and hearing my signal at the base pin of TR1. The EQ itself works as expected, only the gain stage doesn't.
I see 24V at the + pin of C53, but no voltage after that cap. I've exchanged C53, HS1 etc, still no supply voltage there. Any hints for me?
Title: Re: EQN build thread
Post by: briomusic on September 12, 2010, 01:16:32 PM
**edited to remove wrong/misleading info**

if you are seeing DC at C53+ then the next port of call would be R35 (24V-ish on one side 22.5V-ish on the other) and also collector of TR3.
do you see/hear signal at base of TR2? did you double check pin orientation of your particular model of BC184?
Title: Re: EQN build thread
Post by: dandeurloo on September 12, 2010, 01:42:42 PM
Ok, I'll see if I can rig up the tone probe. 

But is there also any test points I can check with my digital meter to see if any votages are out of the range they should be in?

Thanks guys.
Title: Re: EQN build thread
Post by: briomusic on September 12, 2010, 02:50:52 PM
see my reply to holger's post.

I think in your case it's unlikely to be the voltage, but either way you will find where the level drops compared to the good board and that will take you a fair bit close to solving this.
Title: Re: EQN build thread
Post by: dandeurloo on September 12, 2010, 03:33:40 PM
ok, I'll check now. 

Just to confirm what I am hoping to find.
Looking for voltage on c53 - 55.  No voltage on the negaitve side is good.  Also, no voltage at either side of R35 is a good thing.

I'll report back.  Thank you!
Title: Re: EQN build thread
Post by: dandeurloo on September 12, 2010, 03:56:07 PM
ok.  I think I got problems. 

the negative legs voltages are as follows.

c53= 2.5v

c54= .34v

c55= .01v

R35 is 23v

Title: Re: EQN build thread
Post by: peter purpose on September 13, 2010, 07:10:13 AM
Dan,
If I had one to test I'd report back..... but I don't.

As an experiment.. why not stick the smaller R29 in and report back.
If the sound is still good it might save you an awful lot of trouble.

Peter (not a good troubleshooter)
Title: Re: EQN build thread
Post by: dandeurloo on September 13, 2010, 10:02:29 AM
Peter I can do that.  But with the voltage on the negative legs will any damage be done to parts with long term use?

Thanks

EDIT:
I just measured the EQ that I think is working properly.  Here are mu findings:

EQ 2:  the working one
R35= 23.3 on onside and 3.4 on the side closest to TR2

c53= 2.3

c54= .3

c55= .0

So maybe both are wrong here or both are right here?  Briomusic any suggestions.

I'll try swapping R29 once I get back later today.

Thanks guys.
Title: Re: EQN build thread
Post by: briomusic on September 13, 2010, 02:47:58 PM
ok, first of all a correction I was wrong about C53-55 they are in fact part of the out-amp, not PSU bypass. I confused them with C59-60 (which are bypass). To make up for this red herring I offer up a BA283AM-PP schematic, with the components named according to PP-EQN standard and to the best of my knowledge [/disclaimer]:
(http://img.photobucket.com/albums/v426/brio/BA283PPEQN.gif)
The schematic (and transistor voltage table) was borrowed from the EZ1290 documentation and modified by me. If I am in breach of anyones copyrighted artwork let me know. It should help with voltage checking and signal tracing duties.

Please make sure:
1.)...you test all transistors using the hfe function of your DMM. it is not advisable to try them in the circuit with alternative orientations, you might do damage
2.)...the output transformer is connected, this circuit does not function without it.

Lastly, please do not PM me with questions - post them here. that way:
-the info is available for future builders for years to come
-anyone can have a go at helping, not just one person.

thanks.
Title: Re: EQN build thread
Post by: Holger on September 13, 2010, 03:19:15 PM
Thank you very much...
Title: Re: EQN build thread
Post by: peter purpose on September 13, 2010, 10:16:23 PM
Brios's retainer is paying dividends.... cough
Title: Re: EQN build thread
Post by: dandeurloo on September 13, 2010, 10:29:04 PM
K, I just finished a session and measured these quick.  I think I'm probably with in the ballpark on both of these Eq's.  there is a small difference between the 2 eq's but probably not enough to cause 5 db level difference.  I'm gonna try and reflow the board I think.  Is there any place around the input tranny I can check?

EQ1:

TR1
B .89
C 3.64
E .34

TR2
B 3.6
C 21.4
E 3.0

TR3
B 2.4
C 21.4
E 3.1

EQ2:

TR1
B 0.89
C 3.41
E 0.35

TR2
B 3.41
C 21.6
E 2.86

TR3
B2.86
C 21.6
E 2.25

Thanks
Title: Re: EQN build thread
Post by: briomusic on September 14, 2010, 06:05:15 AM
K, I just finished a session and measured these quick.  I think I'm probably with in the ballpark on both of these Eq's.  there is a small difference between the 2 eq's but probably not enough to cause 5 db level difference.  I'm gonna try and reflow the board I think.  Is there any place around the input tranny I can check?

EQ1:

TR1
B .89
C 3.64
E .34

TR2
B 3.6
C 21.4
E 3.0

TR3
B 2.4
C 21.4
E 3.1

EQ2:

TR1
B 0.89
C 3.41
E 0.35

TR2
B 3.41
C 21.6
E 2.86

TR3
B2.86
C 21.6
E 2.25

Thanks

@peter...felt I owed you one  ;)

@dan I don't think DC voltages are your problem, my guess is a bad resistor (10k instead of 1k type of thing) or bad solder joint. have you already tried using the two amp-boards from the good eq?
Title: Re: EQN build thread
Post by: dandeurloo on September 14, 2010, 02:07:43 PM
I reflowed all the solder joints last night and tested it and I think I got it.  I will use them a little and see how they work but I must have had a cold solder joint or something. 

Thanks guys, so far so good!


Title: Re: EQN build thread
Post by: zayance on September 15, 2010, 08:43:15 AM
YEAH BABY! ;D ;D ;D, sounds great so far on quick simple vocal check, Merci monsieur Peter, second one finished also (the other two will have to wait  ;D), just one thing, Briomusic told me on PM a way of doing the clipping calibration using a comp with pushing make up gain for getting to clip the EQ (thr. all the way to no comp of course), i can do that for sure, but i wanted to be able to test that in my bench, i tried one of my pres and it clipped before going IN, and my Sound generator will not go that far in terms of voltage, any tips on doing this in Lab without much fuss ??? Thanks a lot
(http://img96.imageshack.us/img96/1097/gutsr.jpg)
(http://img217.imageshack.us/img217/7035/frontjw.jpg)
(http://img843.imageshack.us/img843/5741/inrack.jpg)
Title: Re: EQN build thread
Post by: kato on September 15, 2010, 08:53:11 AM
Zayance, I like your knobs. What are you using for the small ones?
It's hard finding 4mm shaft knobs in the US. All my searches are coming up empty - at least for knobs that aren't cheap plastic.
Title: Re: EQN build thread
Post by: zayance on September 15, 2010, 08:59:09 AM
Quote
Zayance, I like your knobs. What are you using for the small ones?
It's hard finding 4mm shaft knobs in the US. All my searches are coming up empty - at least for knobs that aren't cheap plastic.

Go Digikey, and type Kilo search field, look for 12.88cm Diameter/3.18mm Shaft (i'm using Sfernice brand Pots, they have 3.18mm shaft) Kilo Knobs don't have 4mm Shaft, view page to have a look of all the options, love these knobs, use a lot of them, nice and clean....
Title: Re: EQN build thread
Post by: kato on September 15, 2010, 09:18:19 AM
Ahhhh! Thank you!  ;D I'm using the same pots.
I was nearing the point of 'bang my head against the wall.' You saved me from buying the wrong knobs because I read the datasheet (http://www.vishay.com/docs/51035/prv6parv.pdf) wrong. Somehow I looked at the 61H pots, not the parv6 in the same sheet.  Whew. Those 1/8" shafts are actually very common and opens up a world of possibilities for knobs. Although I may still go with the Kilos because they look so cool.  Thank you!
Title: Re: EQN build thread
Post by: peter purpose on September 15, 2010, 10:52:52 AM
This is what I'm up to in the knob department at present.

(http://lazpro.com/n1.jpg)

(http://lazpro.com/n2.jpg)
Title: Re: EQN build thread
Post by: zayance on September 15, 2010, 11:32:35 AM
Hmmm looks nice in all Black, maybe next two with ed's input tranny will go all black... Anyway i need to finish calibration and test drive, it's been a while...
Title: Re: EQN build thread
Post by: kato on September 15, 2010, 11:46:16 AM
Ooo yeah, like it. Black knobs, on black surface, with little black lights that light up black to let you know you've done it.   :D
Title: Re: EQN build thread
Post by: haima on September 15, 2010, 11:52:35 AM
my Sound generator will not go that far in terms of voltage, any tips on doing this in Lab without much fuss ???

if you signal generator is too weak you can try boosting on the EQN to get you up to the clipping point. the test waveform will look weird but you can still look for symmetrical clipping... just an idea.
Title: Re: EQN build thread
Post by: Grooveteer on September 15, 2010, 02:14:23 PM


(http://img245.imageshack.us/img245/6365/eqnu.jpg) (http://img245.imageshack.us/i/eqnu.jpg/)

I like Jeff's knobs...  :o  No, wait.. I mean..   ;D
Title: Re: EQN build thread
Post by: dandeurloo on September 15, 2010, 03:58:33 PM
Here is what I came up with for knobs.  Found them at a surplus store.  ;D


(http://www.dandeurloo.com/diy/LAZ%20EQN/laz.jpg)



Title: Re: EQN build thread
Post by: ultra-alex on September 15, 2010, 04:05:41 PM
massive types for the greyhills, but definitely unique. ;)
Title: Re: EQN build thread
Post by: tim-burns on September 16, 2010, 05:49:40 AM
This is what I'm up to in the knob department at present.

Peter
i've got knob envy, whats the brand/part number for your knobs? I've had a look round but can't seem to get the right combo...
cheers
Tim
Title: Re: EQN build thread
Post by: zayance on September 16, 2010, 06:44:53 AM
Just a little update for those who need that info, i've done clipping calibration following Briomusic's tip on that, thanks to him, pretty simple procedure, don't know why i couldn't figure out that by myself ::), meaning using Compressor Make-up gain for boosting the signal on the way up to the EQN, well the figures were looking good without doing nothing, well my trimmers were at unity when received, i believe that's enough for getting to a quiescent point, i trimmed a tad to get it to be precise, so if you don't need precision, then i believe you can skip that part, well that's on my side, but wanted to inform those who don't want to bother and maybe don't have the tools etc....
Title: Re: EQN build thread
Post by: peter purpose on September 16, 2010, 10:38:46 AM
i've got knob envy, whats the brand/part number for your knobs? I've had a look round but can't seem to get the right combo...
cheers
Tim

Tim,
The bigguns are actual BBC knobs and are made of unobtanium.
RS part 465-9886 is similar, but comes without any markings..!! So you'll have to engrave the lines.
The littleuns are RS part 465-9820. I leave the pot shaft length at max and slip a Hellerman sleeve on.

peter

Here's a pic of my bodged engraving job.
(http://lazpro.com/rsknob.jpg)
Title: Re: EQN build thread
Post by: tim-burns on September 16, 2010, 11:38:42 AM
That's great thanks mate.
Unobtainium - that's genius!
Title: Re: EQN build thread
Post by: crisotop on September 18, 2010, 03:58:33 AM
Another question about the Q switch: Peter, you said the higher R17 the sharper the bandwidth of the mid-band - right? But by flicking the Q switch in the "Hi" position R19 is in parallel with R17 thus making the Q of the band wider? Or have I overlooked something

Thanks
Christoph
Title: Re: EQN build thread
Post by: peter purpose on September 19, 2010, 06:49:34 AM
Another question about the Q switch: Peter, you said the higher R17 the sharper the bandwidth of the mid-band - right?
Wrong
But by flicking the Q switch in the "Hi" position R19 is in parallel with R17 thus making the Q of the band wider?
Grab a pair of resistors of the same size and measure them in parallel... report back.
Or have I overlooked something.
See above.
Title: Re: EQN build thread
Post by: crisotop on September 19, 2010, 12:25:23 PM
it doesn't matter how many resistors I stick in parallel, the length of the resistance remains approximately the same - I can only measure longer resistance if I put them in series?  :P

Damnit, I've read that post on page ten two times and still got it wrong - going to shut up for know until it's finished

cheers
Christoph
Title: Re: EQN build thread
Post by: dmp on September 20, 2010, 10:27:32 AM
Page ten, Peter says LOWER resistance than 6.8k makes a sharper Q.
Adding a resistor in parallel to 6.8k will lower the resistance.
Thus: R19 || R17 lowers the resistance and makes a sharper Q
Title: Re: EQN build thread
Post by: crisotop on September 20, 2010, 11:28:14 AM
yeah, yeah - rub it in my face :D

thanks for the double clarification, I got it after reading the post a third time ;)

best, christoph
Title: Re: EQN build thread
Post by: dmp on September 21, 2010, 09:39:20 PM
I got a request for my parts list... so here it is. If it is not here, it was either in the parts kit from Audio Maintenance, or I had it on the shelves already. Use at your own risk; I've only partially assembled mine.

Resistor   820 ohm   299-820-rc   mouser
Resistor   4.7Meg miniature (1/8 watt)   299-4.7M-RC   mouser
Resistor   6.2k   271-6.2k-rc   mouser
Resistor   12 / 2w   594-5083NW12R00J   mouser
Resistor   47 / 2w   97M4543   newark
Pot   50k linear small footprint   785-392C350K   mouser
Q   BC184c   512-BC184C   mouser
Capacitor   470p 2.5mm   490-3656-ND   digikey
Capacitor   680p 2.5mm   490-3755-ND   digikey
Capacitor   1n COG 2.5mm   490-3674-ND   digikey
Capacitor   220p COG 2.5mm   490-3638-ND   digikey
Capacitor   330p COG 2.5mm   490-3723-ND   digikey
Capacitor   470 pf cog 5mm   490-3738-ND   digikey
Capacitor   10uf / 25v tant   74-199D25V10-E   mouser
Capacitor   22uf / 16v tant   74-199D16V22-E3   mouser
Capacitor   47p 2.5mm    140-50N2-470J-TB-RC   mouser
Capacitor   470p 2.5mm   490-3656-ND   digikey
Capacitor   680p 2.5mm   490-3755-ND   digikey
Capacitor   1n COG 2.5mm   490-3674-ND   digikey
Capacitor   68uf/10v small electro   667-EEU-FM1C680   mouser
Capacitor   10pf COG 2.5mm   140-500N2-100J-RC   mouser
Capacitor   180pf COG 5mm   140-50N5-181J-TB-RC   mouser
Capacitor   220p COG 2.5mm   490-3638-ND   digikey
Capacitor   330p COG 2.5mm   490-3723-ND   digikey
Capacitor   470 pf cog 5mm   490-3738-ND   digikey
Capacitor   4.7nf film, 5mm thin   505-MKP24700/630/5   mouser
Tr   MJE3055   512-MJE3055TTU   mouser


Title: Re: EQN build thread
Post by: canidoit on September 21, 2010, 10:02:28 PM
I got a request for my parts list... so here it is. If it is not here, it was either in the parts kit from Audio Maintenance, or I had it on the shelves already. Use at your own risk; I've only partially assembled mine.

Resistor   820 ohm   299-820-rc   mouser
Resistor   4.7Meg miniature (1/8 watt)   299-4.7M-RC   mouser
Resistor   6.2k   271-6.2k-rc   mouser
Resistor   12 / 2w   594-5083NW12R00J   mouser
Resistor   47 / 2w   97M4543   newark
Pot   50k linear small footprint   785-392C350K   mouser
Q   BC184c   512-BC184C   mouser
Capacitor   470p 2.5mm   490-3656-ND   digikey
Capacitor   680p 2.5mm   490-3755-ND   digikey
Capacitor   1n COG 2.5mm   490-3674-ND   digikey
Capacitor   220p COG 2.5mm   490-3638-ND   digikey
Capacitor   330p COG 2.5mm   490-3723-ND   digikey
Capacitor   470 pf cog 5mm   490-3738-ND   digikey
Capacitor   10uf / 25v tant   74-199D25V10-E   mouser
Capacitor   22uf / 16v tant   74-199D16V22-E3   mouser
Capacitor   47p 2.5mm    140-50N2-470J-TB-RC   mouser
Capacitor   470p 2.5mm   490-3656-ND   digikey
Capacitor   680p 2.5mm   490-3755-ND   digikey
Capacitor   1n COG 2.5mm   490-3674-ND   digikey
Capacitor   68uf/10v small electro   667-EEU-FM1C680   mouser
Capacitor   10pf COG 2.5mm   140-500N2-100J-RC   mouser
Capacitor   180pf COG 5mm   140-50N5-181J-TB-RC   mouser
Capacitor   220p COG 2.5mm   490-3638-ND   digikey
Capacitor   330p COG 2.5mm   490-3723-ND   digikey
Capacitor   470 pf cog 5mm   490-3738-ND   digikey
Capacitor   4.7nf film, 5mm thin   505-MKP24700/630/5   mouser
Tr   MJE3055   512-MJE3055TTU   mouser



Thanks dmp, when I have time, I will compare and update parts from my excel version BOM. Keep me posted on how your build goes and how it sounds.
Title: Re: EQN build thread
Post by: kato on September 22, 2010, 07:29:55 PM
I got a request for my parts list... so here it is. If it is not here, it was either in the parts kit from Audio Maintenance, or I had it on the shelves already. Use at your own risk; I've only partially assembled mine.

I guess if we're all sharing parts lists, I've got this one (http://wiki.nimbleswitch.com/EQN) with most of the parts sourced from mouser, complete with alternate sizes on the aml parts for the lead spacing nazis among us. Personally I'm more of a 'bend it to fit' kind of guy these days, but I remember when I thought it mattered on some level.
Title: Re: EQN build thread
Post by: canidoit on September 22, 2010, 07:45:39 PM
I got a request for my parts list... so here it is. If it is not here, it was either in the parts kit from Audio Maintenance, or I had it on the shelves already. Use at your own risk; I've only partially assembled mine.

I guess if we're all sharing parts lists, I've got this one (http://wiki.nimbleswitch.com/EQN) with most of the parts sourced from mouser, complete with alternate sizes on the aml parts for the lead spacing nazis among us. Personally I'm more of a 'bend it to fit' kind of guy these days, but I remember when I thought it mattered on some level.

Thanks Kato!
Title: Re: EQN build thread
Post by: MM1100 on October 02, 2010, 11:15:48 PM
I ended up using the knobs from http://classicapi.com/catalog/index.php?cPath=23_24_40

Here's the parts and cost:
Products
------------------------------------------------------
4 x Plain 5/8" Black Aluminum Knob 1/4" Shaft (1-62-2B-WTIW) = $22.48
3 x Plain 3/8" Black Aluminum Knob 1/8" Shaft (1-37-2A-WTIW) = $14.28
------------------------------------------------------
Sub-Total: $36.76
United States Postal Service (1 x 4oz) (First Class Mail: Estimated 1 - 5 Days): $2.23
Total: $38.99
Title: Re: EQN build thread
Post by: peter purpose on October 03, 2010, 09:09:19 AM
Nice.. they give it a vintage look.
Title: Re: EQN build thread
Post by: Marcocet on October 03, 2010, 10:55:21 PM
So I finally got to finish my second batch but I haven't really gotten to troubleshoot them yet so a few are having problems. The only one I'm really confused by is motorboating like crazy. It's passing signal and working fine but it's oscillating like crazy even with RV4 all the way out. Also, RV5 causes the pitch to change. Any ideas?

Thanks again everyone, especially you Peter! I can't work on them again until next weekend but as soon as they're all in the desk I'll have some photos.

Oh: As a side note I think the faceplates are a little too wide. The new batch seems fine, but the ones from my original batch start to squish everything together. I'm gonna upgrade a few parts to what I used on the second batch next weekend as well so I'll file down the plates then.

Title: Re: EQN build thread
Post by: peter purpose on October 04, 2010, 09:03:14 AM
Any ideas?

Not a one..... but swap out the amps for known good ones at the very start.
Title: Re: EQN build thread
Post by: dandeurloo on October 04, 2010, 11:02:30 AM
i don't have any ideas as well but it would probably help to know if it makes the same noise when the eq's are not engaged or if it's only in one band!

That should help narrow it down for ya.
Title: Re: EQN build thread
Post by: Marcocet on October 04, 2010, 01:38:59 PM
Well, it makes the same noise with the eqs in any setting as well as the unit in bypass and it does it with the opamps removed as well.

Probably something in the power section? I suppose I'll reflow that part of the board first, but I have to imagine it's probably a bad component somewhere? What would even cause oscillation like this?

Thanks for your help! I'll get back at it on friday.


Title: Re: EQN build thread
Post by: mnats on October 11, 2010, 03:47:50 AM
I can't remember ever being so excited to build something as this project. Thanks to Peter and all who contributed to the thread.

Mine worked perfectly from the get-go using a 51X jig, but I'm still waiting for the DC/DC converter to put it into my 500 rack. I've posted some notes on a page here:

http://mnats.net/pp-eqn_notes.html

Careless me - I lost one of the 1mm sockets for the DC converter...if anyone is building a 51X version you should have two to spare. I've got some extra bits and bobs I can trade for another socket if anyone is willing. *edit* - Sorted. Thanks to 12Volts.
Title: Re: EQN build thread
Post by: 12volts on October 11, 2010, 04:33:00 AM
I've built my EQN boards and have 16 surplus 1mm sockets. I'll post few on to you.
Could you send a PM with delivery detail?

Frank
Title: Re: EQN build thread
Post by: peter purpose on October 11, 2010, 05:23:16 AM
Nice EQN page Mako.
The small sockets are just pulled from a turned pin strip... hardly rocking horse poo and cheap as chips anywhere on the planet.

peter
Title: Re: EQN build thread
Post by: mnats on October 11, 2010, 06:38:56 AM
Nice EQN page Mako.

Thanks - hopefully the page is helpful to someone else building this nice project.
The small sockets are just pulled from a turned pin strip... hardly rocking horse poo and cheap as chips anywhere on the planet.

Yeah, the 0.8mm ones I got. It's the 1mm one that I lost. I have a bunch of Mil-Max sockets used for DOAs but they sit too high off the board.

I've PMed 12volts so hopefully this is sorted. Hey, anyone got a spare TDK LAMBDA CC6-2412DF-E they want to sell? *edit* - Sorted. In stock at Digikey again.


Title: Re: EQN build thread
Post by: 12volts on October 11, 2010, 01:41:55 PM
PM received and replied to. Over and out.

Frank
Title: Re: EQN build thread
Post by: Marcocet on October 15, 2010, 04:11:08 PM
Okay, I've fixed most of the ones that had problems but one or two still have issues. They're all in the highpass filter. Either the frequencies are all wrong, or some of the settings are dead etc etc etc. I've checked for shorts everywhere and followed the signal all over the board and I cant seem to find anything wrong. Any suggestions of where I should look in particular? What could cause all of the HP settings to screw up frequency-wise? If it was just one or two I'd think faulty caps but I can't get my brain around this one.

Thanks for any help you can give!!

-marc alan
Title: Re: EQN build thread
Post by: peter purpose on October 15, 2010, 04:36:59 PM
World's worst troubleshooter says... no idea.
If the inductors are sound, then it could be the switch.
Failing that, burn them.
Title: Re: EQN build thread
Post by: dmp on October 15, 2010, 06:56:44 PM
Quote
Either the frequencies are all wrong, or some of the settings are dead etc etc etc.
I'd suggest check the rotary switches with a multimeter. I just finished my pair, and had a similar problem in a couple bands and it was a mistake in putting the stop pins in. Once I figured that out, put the switch back in, they both work great. Awesome project Peter.
Title: Re: EQN build thread
Post by: Marcocet on November 08, 2010, 07:04:21 PM
Okay,

Most of them are working great! Of the few i've had problems with two are most likely in the switches, or beneath them where the resistors were soldered. However all my attempts to remove either have the switches have done is pull up a bunch of the solder mask around the pins! Anybody have any advice on how one would go about desoldering and removing one of the grayhills?

Thanks

-marc alan
Title: Re: EQN build thread
Post by: zayance on November 08, 2010, 07:11:06 PM
Okay,

Most of them are working great! Of the few i've had problems with two are most likely in the switches, or beneath them where the resistors were soldered. However all my attempts to remove either have the switches have done is pull up a bunch of the solder mask around the pins! Anybody have any advice on how one would go about desoldering and removing one of the grayhills?

Thanks

-marc alan


Ouch, Desoldering Grayhill hmmm, possible but you have to be very gentle, i use solder pump most of the time, but for sure if you heat too much or pull to hard you will harm the board, got to pump it as clean as possible each time before atempting any pulling out, i heat up the solder pad, and right away insert the pipe of the pump right on it while pumping out, i stay close to the solder gun when doing, but are you sure it's the switch??? i mean they seem to be tough as a rock  :-\
Title: Re: EQN build thread
Post by: barney on November 08, 2010, 07:58:53 PM
I had a similar thing with wrong freq and no signal but that was because I put the pins in the wrong spot on the hpf.  Might be worth triple checking before trying to unsolder a switch.  Please ignore if you've already tried this.
Title: Re: EQN build thread
Post by: peter purpose on November 08, 2010, 08:45:46 PM
Anybody have any advice on how one would go about desoldering and removing one of the grayhills?


Can't think why you would want to, but I would use a pencil blowtorch and waggle it quickly over the solder.
Works a treat.
Title: Re: EQN build thread
Post by: Marcocet on November 08, 2010, 09:34:04 PM
The reason that I'd want to is that I only just realized that I never cleaned the flux off the board under the switches and I think that's probably what's causing them to short. At least i hope that's the problem, it's all I can figure at this point.

Thanks for the tip! Now to borrow somebody's torch...
Title: Re: EQN build thread
Post by: haima on November 10, 2010, 03:42:18 AM
if you really do need to desolder that grayhill, i'd pick up a hakko 808 kit from ebay - these things are amazing, and really quite cheap. one of my favorite tool purchases ever - you might have a chance at salvaging the part if you use a proper de-soldering gun...
Title: Re: EQN build thread
Post by: briomusic on November 10, 2010, 05:30:05 AM
flux isn't conductive AFAI am aware, and without specialist equipment you are at risk of destroying either the pcb or the switch (or both) by attempting to unsolder the grayhill. I never had to do any cleaning under the switches and built 6 working EQN pcbs. I would double check (with magnifying glass) that there are no shorts where the switches are soldered, as those pins are very close to each other. I recommend a solder tip (and solder wire) smaller than 1mm to do this job. Also, wrongly placed stop pins are a major source of weird behaviour as mentioned above.
Title: Re: EQN build thread
Post by: Marcocet on November 11, 2010, 01:51:31 AM
Well, I got a blowtorch before reading any other responses and got the switches off that way. All looks kosher underneath but I can't figure out what else could be wrong with them at this point, so I cleaned it up a bit. I'm planning to put them back together and test em out on friday. Thanks everybody.
Title: Re: EQN build thread
Post by: JBVries on November 22, 2010, 05:32:01 PM
I got in a 100v 180Pf 5% Multi-layered Ceramic Cap and I was wondering if it will work for C57. It's not C0G but the right value so I thought I would ask. Thanks!

Title: Re: EQN build thread
Post by: bruno2000 on November 22, 2010, 06:22:25 PM
I've had really good luck unsoldering Grayhills with soldering "tweezers" with large (30mm) blades. I paid about $30 US for a pair, and they worked great, since you heat up all of the pins at once.
I have also had (now, the reason for the tweezers) a couple of defective Grayhill switches.  Seems that when they assembled them, they left out one of the wiper assemblies.  After that, I ALWAYS check the switches BEFORE soldering them in,
Just my $0.02 (US)
Best,
Bruno2000
Title: Re: EQN build thread
Post by: canidoit on December 07, 2010, 12:01:20 PM
Is this right, that ALL Cog caps do not require polarity positioning?
Title: Re: EQN build thread
Post by: peter purpose on December 07, 2010, 12:03:31 PM
Is this right, that ALL Cog caps do not require polarity positioning?

yes
Title: Re: EQN build thread
Post by: canidoit on December 07, 2010, 12:48:40 PM
Thanks Pete.

Is there any special requirements regarding the BC184C transistors for the Opamps. Like do they have to be matched or a certain HFE?

To minimize my chances of a noisy transistor like Mako, should I install a certain HFE transistor?
Title: Re: EQN build thread
Post by: peter purpose on December 07, 2010, 12:52:11 PM
I grab the first one out of the bag. There was talk of hfe above 600, but I don't know how true.
Title: Re: EQN build thread
Post by: canidoit on December 07, 2010, 07:09:28 PM
I can't remember ever being so excited to build something as this project. Thanks to Peter and all who contributed to the thread.

Mine worked perfectly from the get-go using a 51X jig, but I'm still waiting for the DC/DC converter to put it into my 500 rack. I've posted some notes on a page here:

http://mnats.net/pp-eqn_notes.html

Careless me - I lost one of the 1mm sockets for the DC converter...if anyone is building a 51X version you should have two to spare. I've got some extra bits and bobs I can trade for another socket if anyone is willing. *edit* - Sorted. Thanks to 12Volts.
Mako, in your weblink you spoke of how you discovered your opamp was the cause of a noise issue. How did you know that?
Was that
- by simple de-solder and replace and see if that was the issue
- is it a common problem solving method of noisy opamps by replacing transistor BC184C
- or you increased HFE on your transistors when you replaced them to increase your chances of solving the issue
- or something else?

Thanks
Title: Re: EQN build thread
Post by: briomusic on December 08, 2010, 04:27:24 AM
I don't think Mako's noise problem was related to the hfe value of the transistor, but rather due to an actually faulty component. The chance of this happening is rather low. I have built 6 EQNs (including 12 opamps) and didn't have any problems with noise. what I have heard about the BA283 stage in general (this is the output stage used in the EQN - NOT the opamp) is to use high-hfe transistors for the first BC184 in the darlington configuration, this would be TR2 on the mainboard. I usually try and find one with over 600 hfe, but I haven't actually ever made a test to see how much difference it makes. I wouldnt worry about this too much, if a transistor turns out to be faulty, just swap it out, they are not exactly expensive.
Title: Re: EQN build thread
Post by: canidoit on December 08, 2010, 05:49:21 AM
Anyone experience with this build notice anything wrong with my opAmps, like do the transistors face correctly?
(http://www.diy.ine-kpro.com/laz1084/journey/opAmp2.jpg)

My pin configuration for the BC184C looks like this.

Flat top
L-C-R
Curved bottom

The center leg bends backwards to fit in the PCB middle hole for that transistor?
Title: Re: EQN build thread
Post by: canidoit on December 08, 2010, 10:22:21 AM
Pete on your BOM it sais R19 is 7.5K. I have read people using 4.53K for R19 to get the unit working like a 1073, 1084 EQ.

Why have you set R19 at 7.5K instead. Is this a sharper or wider Q and does it sound better?
Title: Re: EQN build thread
Post by: dmp on December 08, 2010, 10:37:57 AM
Quote
Pete on your BOM it sais R19 is 7.5K. I have read people using 4.53K for R19 to get the unit working like a 1073, 1084 EQ.
Why have you set R19 at 7.5K instead. Is this a sharper or wider Q and does it sound better?
This is discussed on Page 10 and then again on page 15.
Title: Re: EQN build thread
Post by: JBVries on December 08, 2010, 11:09:43 AM
Anyone experience with this build notice anything wrong with my opAmps, like do the transistors face correctly?
My pin configuration for the BC184C looks like this.

Flat top
L-C-R
Curved bottom

The center leg bends backwards to fit in the PCB middle hole for that transistor?

Yes you will have to bend the emitter back a little bit but that's no big deal. I just compared your pic to my op-amps that just happen to be sitting here as I finished them last night and they look fine to me.  Maybe Peter can confirm though  ;D
Title: Re: EQN build thread
Post by: canidoit on December 08, 2010, 05:12:11 PM
Yes you will have to bend the emitter back a little bit but that's no big deal. I just compared your pic to my op-amps that just happen to be sitting here as I finished them last night and they look fine to me.  Maybe Peter can confirm though  ;D
I think it's important for eagle eye overview of correct completed boards for newbies who like visual confirmation of their build. Thanks JB  :)

This is discussed on Page 10 and then again on page 15.
Thanks dmp, yeah I have read those posts, about the sharper and wider Q but I am very curious as to why Pete would do the 7.5K if it's not similar to a 1073/1084 setup when using the 4.53K. So I am thinking maybe its a magic EQ settings that sounds better maybe? Just want to know my options before making the solder of the part.
Title: Re: EQN build thread
Post by: dmp on December 08, 2010, 05:21:04 PM
Quote
magic EQ
I think what is most important is to use a resistor made of fairy dust... haha, just kidding.
Title: Re: EQN build thread
Post by: peter purpose on December 09, 2010, 07:09:22 AM
Best to use the extremely rare Com-Mon-sen5e components.
Leave them near the pcb overnight and they'll find their own way.

(http://farm2.static.flickr.com/1135/991430430_b89eecdf38.jpg)
Title: Re: EQN build thread
Post by: Marcocet on December 09, 2010, 02:03:15 PM
Hey, how'd you get that picture of my feet?

Title: Re: EQN build thread
Post by: JBVries on December 14, 2010, 06:18:06 PM
Just to make things a little easier on future builders. Make sure you have the flat part of the shaft opposite position 2 and drop pins in these locations....

12 and 6
12 and 8
12 and 5
12 and 5

Left to right...

(http://i11.photobucket.com/albums/a174/mrmizuno1/EQN-pins2.jpg)

If this is incorrect please give a shout so I can take this down but I'm pretty sure it's right.
Title: Re: EQN build thread
Post by: canidoit on December 17, 2010, 03:26:22 AM
JBVries, thanks, that has come in handy!

Can someone please tell me what goes to these following holes circled in green and what is the purpose of them? There are 7 of them that I have circled.
eg. 2- you put the header pins there so that you can jumper them for calibration?

(http://www.diy.ine-kpro.com/laz1084/unknown/eqn-unknown1.jpg)

Also the HS1 heatsink's legs, are you soldering those to the PCB board? I tried soldering them but I can't get the solder to stick on the legs??


Thanks
Title: Re: EQN build thread
Post by: JBVries on December 17, 2010, 03:34:02 AM
Are you asking as a hypothetical question or a literal question? I think some of the holes you outlined are just left empty as they were likely part Peter's prototyping/final troubleshooting process that became superfluous to the build.

With HS1 you just gotta turn up the heat on your soldering iron. They should solder in just fine although I just did one for stability, and that way less heat is dissipated directly to the PCB.
Title: Re: EQN build thread
Post by: 12volts on December 17, 2010, 04:21:37 AM
JBVries, thanks, that has come in handy!

Can someone please tell me what goes to these following holes circled in green and what is the purpose of them? There are 7 of them that I have circled.
eg. 2- you put the header pins there so that you can jumper them for calibration?

(http://www.diy.ine-kpro.com/laz1084/unknown/eqn-unknown1.jpg)

Also the HS1 heatsink's legs, are you soldering those to the PCB board? I tried soldering them but I can't get the solder to stick on the legs??


Thanks


They are known as vias. They are used to transfer signal or power tracks to the opposite side or layer of a board
to make routing easier. Sometimes things are more simple than you think. :O)


Frank
Title: Re: EQN build thread
Post by: canidoit on December 17, 2010, 06:04:33 AM
Thanks guys!

I just don't want to miss a step.

As you know, I am not that electronically inclined as some of you folks.  ;)

Did any of you guys get nuts and bolts with your Mini 1066 transformer or EQN kit or do you have to source them yourself?
Title: Re: EQN build thread
Post by: dmp on December 17, 2010, 11:26:56 AM
I believe what you have circled as 2 is for a three pin header. If I recall correctly it terminates the output transformer with R37 if a jumper is installed (600 ohms). Look at the traces to see if this makes sense.
Title: Re: EQN build thread
Post by: canidoit on December 17, 2010, 05:56:31 PM
Is there info on how to calibrate this build? I have read zayance post but do not understand what he is talking about?

What is the most cost effective way of building a test rig for my 500 series builds?

Can I buy a 16 volt laptop charger and use that for power?

Where do I get those blue API socket that is in my lunchbox and what part number are they so I know what to buy?

How should I wire the tab at the back of this build to test it out of the API lunchbox?

Thank you

Title: Re: EQN build thread
Post by: JBVries on December 17, 2010, 06:10:19 PM
Jeff @ classicapi.com has the sockets.

I think you could just build a power supply like the ones APP makes (http://www.groupdiy.com/index.php?topic=33576.0) and be on your way.

(somebody please correct me if I'm wrong.)

I'm not trying to bust your chops, but try to spend some time SEARCHING around the forum and you will find most everything you are looking for. Use "parenthesis" to search for exact text "51x socket" or whatever and only select rooms that would be applicable (IE: The lab, Drawing board, maybe the markets).
Title: Re: EQN build thread
Post by: mikefatom on December 17, 2010, 06:15:31 PM
Get the edge connector from Jeff, Cemal or Volker.  Make sure you get the 51X connector which has 36 connectors.  You will be able to use it for your 500 builds as well as your 51X builds!

Build yourself a simple connection kit like I've done here:
http://www.groupdiy.com/index.php?topic=41312.msg518780#msg518780

Good luck,

Mike
Title: Re: EQN build thread
Post by: canidoit on December 27, 2010, 07:57:20 PM
Thanks  :)

Peter, any reason why you did not use a linear regulator instead of a DC-DC converter for this build? I have read that it jeopardizes the quality of audio in the unit.

Also what is the calibration procedure for these units, I have searched and can not find any proper information.
Title: Re: EQN build thread
Post by: peter purpose on December 27, 2010, 09:01:42 PM
Ask Colin why he does, not why I didn't.
Adjust rv5 for symetrical clipping.
Title: Re: EQN build thread
Post by: JBVries on December 28, 2010, 01:42:55 AM
Peter,

Am I to gather there could be a better part in my EQNs than is currently? If so, could you recommend a linear reg that would be compatible?
Title: Re: EQN build thread
Post by: haima on December 28, 2010, 01:58:50 AM
JBVries - i think both Peter and Colin have chosen different ways to skin the "+/-16v-to-24v" cat - they both have their reasons for choosing the path they have taken... neither are wrong.

Is there something in particular you are unhappy about with the sound of your EQNs? Mine sound awesome. No noise or other issues.

There are hundreds (thousands?) of satisfied users of the Great River 500 series preamps, onlymee N73 preamps & EQN eqs - all these modules use the same TDK DC-DC converter and surrounding circuitry AFAIK (unless you are using the 51X pins on the latter two).

You can't easily drop in a linear regulator in place of a DC-DC converter - it would require some modifications to the circuit and board - if i was you i'd keep you EQNs stock and enjoy them, unless there is an actual problem that needs fixing.

BUT this is DIY so you can do what you want - Just don't expect Pete to help you redesign his EQ.... i imagine he's got better things to do.
Title: Re: EQN build thread
Post by: JBVries on December 28, 2010, 02:09:01 AM
Thanks Haima,

As an admitted novice and also a so called "Muso" (musician in a rush for best musical quality) ;D I didn't mean to offend or imply that anything was lacking and please don't take my ignorance as such. Still have yet to do the final power up but I just wanted to make sure that everything was the way it should be as I know builds can change and Mods happen.

Cheers and thanks for the reply.

Pete - please go ahead an disregard that question.
Title: Re: EQN build thread
Post by: haima on December 28, 2010, 02:13:28 AM
No probs - I too have wondered about the DC-DC converter... and if there's another way - but in practice they work well in this application.

AFAIK there is no errata for this build - it all works as intended  :)

Finish off your EQNs and i'm sure you'll enjoy them - i've been using my pair extensively. Love them!
Title: Re: EQN build thread
Post by: crisotop on January 04, 2011, 05:01:51 AM
I bought my kit in the blackmarket and am missing the heatsink - anything special about it (besides that it should fit the board)?

thanks!
christoph
Title: Re: EQN build thread
Post by: JBVries on January 04, 2011, 05:06:04 AM
Nope, it is definitely more robust than your run of the mill V reg heatsink but aside from that no apparent differences.
Title: Re: EQN build thread
Post by: crisotop on January 04, 2011, 05:11:22 AM
Thanks - that's why I'm asking, don't know if I should look for specific dissipation values, because it looks much thicker than the heatsinks I've got at home.
Title: Re: EQN build thread
Post by: peter purpose on January 04, 2011, 06:47:41 AM
If you want the right thing.... Farnell 1703179
Title: Re: EQN build thread
Post by: crisotop on January 04, 2011, 07:24:59 AM
wicked - thanks peter!
Title: Re: EQN build thread
Post by: crisotop on February 02, 2011, 03:15:56 PM
my pair is finally up and running - thanks for the easy layout / build. Are you guys using any altered termination on the output trafo? My frequency response is a bit "off" at the very low and high end (~3dB down). As far as I can make out R37 is the 600 Ohm load - is C61 (C62) parallel to R37?

Thanks!
Christoph
Title: Re: EQN build thread
Post by: peter purpose on February 03, 2011, 03:21:50 AM
As far as I can make out R37 is the 600 Ohm load - is C61 (C62) parallel to R37?

R37 is the load.
No... c61 c62 are not parallel to r37.

3dB down at what frqs?
Title: Re: EQN build thread
Post by: crisotop on February 03, 2011, 03:11:33 PM
just measured again, with a more precise method. It's not as drastic anymore. 1.5dB down at 20K, unity gain from 7k down to 900, then back to 1.5dB down at 20Hz. Not that I worry much, but my other "Nevish" builds have quite the noticable frequency bump in the very lows and highs, that's why I'm wondering.

Thanks for the support Peter!
Christoph
Title: Re: EQN build thread
Post by: canidoit on February 09, 2011, 06:15:16 PM
Pete,

How much current does this build take.
Title: Re: EQN build thread
Post by: peter purpose on February 10, 2011, 08:42:13 AM
Pete,

How much current does this build take.

Within specification.
Title: Re: EQN build thread
Post by: JBVries on February 17, 2011, 01:13:20 AM
Two EQNs........

No Smoke!!! ;D but no sound either....... the hunt begins.

How are we supposed to set the two variable resistors?

 Also, nowhere on the boards including the heatsink are showing any expected temperature variation almost as if voltage were present at the tabs but not going any where beyond that. Anywhere I can poke to make sure voltage is getting to the right place? If so, proper value expected?

Cheers! 
Title: Re: EQN build thread
Post by: canidoit on February 17, 2011, 03:33:55 AM
Two EQNs........

No Smoke!!! ;D but no sound either....... the hunt begins.

How are we supposed to set the two variable resistors?

 Also, nowhere on the boards including the heatsink are showing any expected temperature variation almost as if voltage were present at the tabs but not going any where beyond that. Anywhere I can poke to make sure voltage is getting to the right place? If so, proper value expected?

Cheers! 
I set mine at 750r from what I recall, because that was like the safe zone as discussed in a few of the posts but I recall only discussing 1 resistor to adjust. Are we both on the same page?  ???
Title: Re: EQN build thread
Post by: JBVries on February 17, 2011, 04:18:13 AM
No, you are thinking of the bandwidth resistor. I am talking about the variable resistors pots (the ones with a set screw).
Title: Re: EQN build thread
Post by: canidoit on February 17, 2011, 05:46:17 AM
No, you are thinking of the bandwidth resistor. I am talking about the variable resistors pots (the ones with a set screw).
You mean the little blue trimmer pots? If so, you are meant to use an oscilloscope and measure for clipping.

I do not recall having to change any resistors besides that 750r one.

Have a look at the BOM I have, I referred to two parts list I received from two builders here before making my own parts list. Maybe the solution is in there??

I would like to know as well incase I did something wrong?
Title: Re: EQN build thread
Post by: peter purpose on February 18, 2011, 08:19:50 AM
jbv,
Are you 51x, or standard?
Title: Re: EQN build thread
Post by: JBVries on February 19, 2011, 02:54:16 AM
I was testing with +-16v on my test little jig. I do use 51x and when I threw one in the rack I had no difference in results.
Title: Re: EQN build thread
Post by: peter purpose on February 19, 2011, 06:30:31 AM
I'll re-phrase... is it fully populated, or are you in 51x mode?
Title: Re: EQN build thread
Post by: JBVries on February 19, 2011, 11:15:20 AM
Ahhh, 51x.
Title: Re: EQN build thread
Post by: peter purpose on February 19, 2011, 06:27:06 PM
Then plus and minus 16v is nfg. Feed it 24v.
Title: Re: EQN build thread
Post by: JBVries on February 19, 2011, 07:42:02 PM
Bollox!! (and i'm not taking the piss I do say that all the time, even though I'm coastal Californian, haha ;))


C60 started to go as soon as I jumped that spot on CC6 and fed it 24v. I heard it first then saw it start to bulge so I killed power. If I find the problem will that cap still be ok, or is it shot already?

and  Orientation and general assembly form aside(as I'm triple checking that now), any advice on where to look would be greatly appreciated.
Title: Re: EQN build thread
Post by: peter purpose on February 19, 2011, 08:17:08 PM
any advice on where to look would be greatly appreciated.

C60 and everything else..!!
Title: Re: EQN build thread
Post by: JBVries on March 07, 2011, 11:27:50 PM
So close I can taste (or hear) it.....

Is there supposed to be significant level coming out of the OUT(-) of the input transformer? When probed I see very little signal.

When I poke around I do see signal various places all over the board. Plenty of signal out of the op amps, but still nothing at the output.

Any thoughts much appreciated.
Title: Re: EQN build thread
Post by: crisotop on March 08, 2011, 03:03:50 AM
Quote
Plenty of signal out of the op amps, but still nothing at the output.

Follow the schematic from the opamps to the output - somewhere along these lines you might have got a problem.

Good Luck!
Christoph
Title: Re: EQN build thread
Post by: peter purpose on March 09, 2011, 12:50:23 AM
Is there supposed to be significant level coming out of the OUT(-) of the input transformer?

No. The negative output goes to ground.
Title: Re: EQN build thread
Post by: JBVries on March 09, 2011, 06:56:16 AM
I did get one of them running..... Sounds beautiful. Thank you much for the great projects Peter!
Title: Re: EQN build thread
Post by: Marcocet on April 12, 2011, 08:13:03 PM
Okay, ran up on a problem I can't solve.

On one of my EQs the High Pass filter is WAY too high. As in when it's set to 45 its cutting at like 4k. I've replaced caps 11-18, all the resistors on the switch and the two tantalum caps and nothing's changed. I can't figure out what else in the circuit it could even be. Anybody have any insight?

Thanks
Title: Re: EQN build thread
Post by: ruairioflaherty on April 12, 2011, 08:22:32 PM
Okay, ran up on a problem I can't solve.

On one of my EQs the High Pass filter is WAY too high. As in when it's set to 45 its cutting at like 4k. I've replaced caps 11-18, all the resistors on the switch and the two tantalum caps and nothing's changed. I can't figure out what else in the circuit it could even be. Anybody have any insight?

Thanks

Hi Marc,

Don't have the schemo handy and mid session anyhow but it sounds like a component factor to me, it's probably cutting at 4500Hz, ie 100 times what it should be.  Are all the high pass values on that one unit similarly elevated?  If so then it could be a rogue resistor in the wrong bin or even marked wrong.  Did you measure them all when fitting?

Cheers,
Ruairi
Title: Re: EQN build thread
Post by: Marcocet on April 12, 2011, 10:27:05 PM
Okay, ran up on a problem I can't solve.

On one of my EQs the High Pass filter is WAY too high. As in when it's set to 45 its cutting at like 4k. I've replaced caps 11-18, all the resistors on the switch and the two tantalum caps and nothing's changed. I can't figure out what else in the circuit it could even be. Anybody have any insight?

Thanks

Hi Marc,

Don't have the schemo handy and mid session anyhow but it sounds like a component factor to me, it's probably cutting at 4500Hz, ie 100 times what it should be.  Are all the high pass values on that one unit similarly elevated?  If so then it could be a rogue resistor in the wrong bin or even marked wrong.  Did you measure them all when fitting?

Cheers,
Ruairi


Stupidly I didnt on this batch. I swapped out all the resistors and caps that I know are in the hpf section though. I'm gonna keep trying to trace it and see if I spot anything else.
Title: Re: EQN build thread
Post by: ruairioflaherty on April 12, 2011, 10:50:45 PM
Hey Marc,

If you pulled the parts from the same bins as the other builds the chances are small but still there that you grabbed a 100R instead of a 10K or something like that, or your cap is 100 times too small....  The other thing it could be is short around the resistors, a very low resistance there would elevate the HPF frequency. 

Are all the HPF frequencies out or just the 45Hz?

Is there a schemo somewhere for the EQ-N, can't find it (and I have a pair to build at some point)

Cheers,
Ruairi
Title: Re: EQN build thread
Post by: Marcocet on April 12, 2011, 11:38:56 PM
it was an inductor! Anybody have a source for 9043's in the states?

Title: Re: EQN build thread
Post by: ruairioflaherty on April 12, 2011, 11:58:38 PM
Hey Marc,

The inductor is use on the HPF??  I always thought that was in the low frequency eq band.  Anyhow I don't think there's any U.S. distribution for the Carnhill stuff.

I've got a pair of 9043 here but I'm halfway through prototyping an LC mastering eq and I've used one for that.  If you're stuck for one quickly I can send you one of mine from California and you can have Colin send one directly to me? (I guess he'll  replace it for you as you've bought so many).

Are you sure it was the inductor? Seems weird to me...

Cheers,
Ruairi
Title: Re: EQN build thread
Post by: peter purpose on April 14, 2011, 01:38:02 PM
Ruairi, HPF is LC based.
Marc.... have you stuck an inductance meter on it? Seems odd that an inductor would fail.
Title: Re: EQN build thread
Post by: ruairioflaherty on April 14, 2011, 01:44:04 PM
Hey Peter,

I didn't know that, I need to dig me up a 1084 schematic.  I robbed the 9043 from my kit for an LC eq I'm working on and I can report that it makes for a rather righteous sounding low end when used as a shelf/bell.

Hope all is well back on the mainland..

Cheers,
Ruairi



Title: Re: EQN build thread
Post by: Marcocet on April 14, 2011, 04:43:37 PM
Ruairi, HPF is LC based.
Marc.... have you stuck an inductance meter on it? Seems odd that an inductor would fail.

That's why it's the very last thing I checked (after pulling every resistor half way off the board and testing them as well as swapping the grayhill and all of the caps in the HPF section). But I swapped it out and problem solved.

I plan on testing the one I've got thoroughly as soon as I get the time to figure out how. Never tested an inductor before, but it doesn't seem like it should be too complicated.

I'll just order a replacement from Colin. I'm in need of another grayhill for a different project anyway. Thanks everyone!
Title: Re: EQN build thread
Post by: shabtek on April 14, 2011, 05:32:41 PM
could be it is "pinned-out" wrong
you could test the resistance against a working one
Title: Re: EQN build thread
Post by: ruairioflaherty on April 14, 2011, 06:24:21 PM
Never tested an inductor before, but it doesn't seem like it should be too complicated.

Hey Marc,

I just happen to have the DCR measurements for my pair of 9043 open

Tap 1 - 1.3H - 237 Ohms
Tap 2 - 3H - 373 Ohms
Tap 3 - 7H - 600 Ohms
Tap 4 10H - 738 Ohms

That's give you an idea what's happening at least.

Cheers,
Ruairi
Title: Re: EQN build thread
Post by: Marcocet on April 15, 2011, 05:32:45 PM
Thanks!!
Title: Re: EQN build thread
Post by: jandoste on May 09, 2011, 01:43:45 PM
Hi Peter,
I didn't find any info for the J1  ??? What I need to do for that?
Thanks,
Title: Re: EQN build thread
Post by: peter purpose on May 09, 2011, 01:52:52 PM
A three way .1" header and a jumper, or just stick in a little wire.
Title: Re: EQN build thread
Post by: jandoste on May 09, 2011, 03:43:04 PM
so like this...

(http://i1236.photobucket.com/albums/ff442/jandoste/xinf.jpg)

cheers,
Title: Re: EQN build thread
Post by: peter purpose on May 09, 2011, 03:46:50 PM
No
Title: Re: EQN build thread
Post by: briomusic on May 10, 2011, 10:47:08 AM
that'll be, cos it's not calibrated  :D

(RV4!)
Title: Re: EQN build thread
Post by: jandoste on May 10, 2011, 12:33:16 PM
that'll be, cos it's not calibrated  :D

(RV4!)


Great!
Brio,Thanks,
Did it and it works   :D :D
Cheers,
 
Title: Re: EQN build thread
Post by: jandoste on May 10, 2011, 12:49:20 PM
I got some hum noise [50-64hz].
any idea ?
Thanks,
Title: Re: EQN build thread
Post by: peter purpose on May 10, 2011, 02:05:17 PM
What are you using for power?
Title: Re: EQN build thread
Post by: jandoste on May 10, 2011, 02:34:24 PM
What are you using for power?

API Lunchbox.
Title: Re: EQN build thread
Post by: peter purpose on May 10, 2011, 04:40:54 PM
Could be a bad dc-dc.... do you have a spare?
Title: Re: EQN build thread
Post by: jandoste on May 10, 2011, 05:41:44 PM
Could be a bad dc-dc.... do you have a spare?

Thanks Peter,
Yeah, I tried with other one but it's the same :( just one unit has the hummmm .
maybe wire connection problem or maybe I soldered R27 with dc :( because they are so close...
Title: Re: EQN build thread
Post by: peter purpose on May 13, 2011, 09:55:02 AM
Did you sort it?
Title: Re: EQN build thread
Post by: jandoste on May 13, 2011, 01:40:56 PM
Did you sort it?

Hi Peter,
I got the same problem. I tried with seconde one but same...
maybe it's just the grnd problem?
Thanks,
Title: Re: EQN build thread
Post by: peter purpose on May 13, 2011, 07:09:59 PM
You've either done something wrong, or you've done something wrong then... cough.
Title: Re: EQN build thread
Post by: bobschwenkler on June 03, 2011, 03:10:08 AM
Hey All, I just skimmed through the first couple pages and didn't see an answer, forgive me if it's been asked already: What's the cost for one of these units run in USD?
Title: Re: EQN build thread
Post by: jensenmann on June 03, 2011, 07:36:46 AM
Regarding hum: is your 1084 placed near the PSU? If so move it to the slot farest from the PSU. Try to shield the inductors with some brass (iron! not aluminium, not copper).
Title: Re: EQN build thread
Post by: jandoste on June 03, 2011, 06:16:43 PM
Regarding hum: is your 1084 placed near the PSU? If so move it to the slot farest from the PSU. Try to shield the inductors with some brass (iron! not aluminium, not copper).

Hi Jensen,
Yep, it is near the PSU... Will try it.
Thanks,
Title: Re: EQN build thread
Post by: bobschwenkler on June 05, 2011, 09:13:13 PM
Is there a schematic for this unit?
Title: Re: EQN build thread
Post by: peter purpose on June 06, 2011, 08:46:00 AM
There is.
Title: Re: EQN build thread
Post by: bobschwenkler on June 06, 2011, 11:51:00 AM
Where can I find this schematic?
Title: Re: EQN build thread
Post by: peter purpose on June 06, 2011, 12:33:16 PM
Page 6
Title: Re: EQN build thread
Post by: bobschwenkler on June 06, 2011, 12:38:06 PM
Thanks! As a suggestion to help out other newcomers like me it would probably be helpful to have it in a more visible spot, like the first page of this thread or the EQN website.
Title: Re: EQN build thread
Post by: dmp on June 26, 2011, 09:49:03 PM
So I've noticed both of my EQNs have a low frequency sputtering noise. With no signal, they both put out about -55 dB (into a +4db soundcard input). It sounds like wind on a microphone. Turning up the HPF stops it. Any ideas? Any else noticed this? I'm using them in a 51x rack.
Title: Re: EQN build thread
Post by: canidoit on July 24, 2011, 07:03:25 AM
 :)
Title: Re: EQN build thread
Post by: dmp on July 24, 2011, 09:55:59 AM
This is my understanding:
RV4 sets the level of the EQ. It's purpose is to match the signal level to unity.
So run a signal through the EQ in bypass and observe the level, then engage the EQ and match the level using the trimpot.

RV5 is adjusted to get symmetric clipping. If you cannot see the signal clipping on your scope, then your signal is not high enough. Since you are using a signal from a macbook pro it is not surprising that you cannot clip the EQN. You need a signal of several volts to get a Neve circuit to clip.
Title: Re: EQN build thread
Post by: onlymeeee on July 24, 2011, 10:55:14 AM
Boost at around 1k or whatever with the eq .. that'll give you 18dB or whatever extra gain before the output stage

Title: Re: EQN build thread
Post by: canidoit on July 24, 2011, 11:08:34 AM
This is my understanding:
RV4 sets the level of the EQ. It's purpose is to match the signal level to unity.
So run a signal through the EQ in bypass and observe the level, then engage the EQ and match the level using the trimpot.

RV5 is adjusted to get symmetric clipping. If you cannot see the signal clipping on your scope, then your signal is not high enough. Since you are using a signal from a macbook pro it is not surprising that you cannot clip the EQN. You need a signal of several volts to get a Neve circuit to clip.
Thanks DMP, I will try that on the RV4
Title: Re: EQN build thread
Post by: ShandonSound on August 05, 2011, 02:26:08 PM
Hi,

Could anyone share the part numbers they used for R27 & R32? I have mouser part no.s 66-GS3T012J (R27) & GS3-100-47R0JLF (R32) but thy seem far too big to fit neatly on the board?

Thanks,

Steve
Title: Re: EQN build thread
Post by: peter purpose on August 05, 2011, 03:35:03 PM
They are 0.5" pitch... so anything with a smaller body than that will do you.
Title: Re: EQN build thread
Post by: ShandonSound on August 06, 2011, 02:08:15 PM
They are 0.5" pitch... so anything with a smaller body than that will do you.

Sorry, I'm pretty new to DIYing and lack knowledge (and confidence) when it comes to sourcing parts but I've found these, are they ok?

Thanks again,
 

71-CPF212R000FKE14
(http://uk.mouser.com/ProductDetail/Vishay/CPF212R000FKE14/?qs=nHuOPoDtCcQ0W7e%252bm%252bMk7g%3d%3d)

594-5083NW47R00J
(http://uk.mouser.com/ProductDetail/Vishay-BC-Components/PR02000204709JR500/?qs=sGAEpiMZZMu61qfTUdNhG%2f4r7Iw6CIkyujIHaiAeRPI%3d)
Title: Re: EQN build thread
Post by: peter purpose on August 06, 2011, 03:38:07 PM
Both of those should do you, but if you're in the UK go to one of the UK distributors.
Farnell, RS and Rapid spring to mind.
Title: Re: EQN build thread
Post by: ShandonSound on August 27, 2011, 02:07:57 PM
Calibrating RV5?
I've been trying to follow the calibration guide on the 'journey' thread but I don't seem to be able to make RV5 have any impact on the shape of the sine wave how ever far I turn it cw or ccw. Currently the sine wave is slightly blunt at the bottom when sending 1khz at 0dbu and if I try to boost the gain as suggested on the other thread it ceases to look anything like a symmetrical sine wave.

Any suggestions/guidance anyone?

Thanks,

Steve
Title: Re: EQN build thread
Post by: ShandonSound on August 28, 2011, 05:29:07 PM
OK ignore that last post (oh you were anyway!):) I'm continuing to troubleshoot and hope I'm making progress. No doubt I'll be back with some really rudimentary questions.
Title: Re: EQN build thread
Post by: peter purpose on August 28, 2011, 06:32:33 PM
Did someone say something?
Title: Re: EQN build thread
Post by: canidoit on August 29, 2011, 12:00:38 AM
if I try to boost the gain as suggested on the other thread it ceases to look anything like a symmetrical sine wave.
Hi mate, the dreaded callibration process  :(

What shape does it exactly do when you boost the signal?

Can you post up a pic.

Your signal could be already distorted when it goes into the EQN, so it giving you a funny shape when boosting into the EQN. From my understanding, you need to have a clean but high gain signal into the EQN and the distortion is meant to come from the EQN's inner working, and you adjust it so that the clipping is even at top and bottom as shown in the oscilloscope.

What devices are you using in doing your calibration. eg. laptop, what preamp, etc.

Also dont be afraid to play around with combinations of turning the RV4 and RV5 trim pot and boosting the signal to try to attain that top and bottom, even clipping, cause that's how I finally ended up with the final result and my unit sounds great with the limited time I have had to use it. I hope to assign more time to it in the future : ))))
Title: Re: EQN build thread
Post by: ShandonSound on August 29, 2011, 03:07:26 PM
Thanks for the reply.
I found I'd made a stupid mistake with terminating the input transformer but that is now sorted so my earlier post is probably best ignored for now.
I am a bit confused about J1 though, the scant references I have found to it are a bit confusing to me. I have now shorted across the three pins and have something which sounds much more like full range audio, is this the right thing to do?
Assuming J1 is now correct I seem to have a surprising drop in level when putting signal through the EQN. Is this just a question of calibrating RV4 & 5 correctly? Do both of these affect level as only RV4 seems to make any difference at the moment?

Cheers
Title: Re: EQN build thread
Post by: zayance on August 30, 2011, 06:45:47 AM
Thanks for the reply.
I found I'd made a stupid mistake with terminating the input transformer but that is now sorted so my earlier post is probably best ignored for now.
I am a bit confused about J1 though, the scant references I have found to it are a bit confusing to me. I have now shorted across the three pins and have something which sounds much more like full range audio, is this the right thing to do?
Assuming J1 is now correct I seem to have a surprising drop in level when putting signal through the EQN. Is this just a question of calibrating RV4 & 5 correctly? Do both of these affect level as only RV4 seems to make any difference at the moment?

Cheers

Go thru the build thread, you'll find your answers, beside maybe some assembly mistake?
Title: Re: EQN build thread
Post by: peter purpose on August 30, 2011, 08:33:01 AM
J1.... top pin connects to nothing.
Middle and bottom jumped together puts R37 across the transformer secondaries.

(http://lazpro.com/j1.jpg)

Check your input transformer connections are correct wrt level loss.
Title: Re: EQN build thread
Post by: ShandonSound on September 03, 2011, 02:42:25 PM
OK, still in calibration hell so here's hoping someone can help me narrow down the problem...
My set up:
I've got an EQN in slot 1 of 51X Rack
I'm feeding a sine wave from Logic to output 8 of a Metric Halo interface. The sine wave is into the red in Logic as per the 'journey' thread description.
Output goes to the EQN input and the EQN output comes back into the interface on input 1 and I am then using the oscilloscope in Audiofile Engineering's 'Spectre' software.
RV4 turns the level up and down as expected and the level between the EQ being 'in' and 'bypassed' is very consistent. The level however is a bit lower than the signal I am sending. So if I send tone at -12, say, I can't get Spectre to meter as high as -12 even if the I turn RV4 full up.(?) I've checked, and checked and re checked the transformer wiring and I don't think it's that!
Despite this I can turn RV4 up to make the sine wave clip (at the top) and turning RV4 down produces a nice symmetrical sine wave.
I can't make RV5 effect the shape of the wave at all though.
I have tried inserting a preamp to boost the level of the signal and this produces some very distorted shapes on the oscilloscope, but whilst RV4 can turn them up and down, and bring the sine wave back into symmetry, I've yet to find a level where RV5 will do anything.

Any input would be very welcome.

Many thanks,

S.
Title: Re: EQN build thread
Post by: peter purpose on September 03, 2011, 03:31:24 PM
Stick in a 1k6 signal and boost it with the eq.... should get you plenty of level.
Title: Re: EQN build thread
Post by: canidoit on September 04, 2011, 03:00:01 AM
ShandonSound, I think you still need a preamp after the halo to boost it high enough into the EQN. Try Pete's suggestion cause apparently people were able to get enough levels by boosting it with an EQ. Not sure if they did it in the software though, because I would think that through the software would just clip the signal on the laptop outputs.

Do you have access to a preamp?
Title: Re: EQN build thread
Post by: ShandonSound on September 04, 2011, 12:57:50 PM

Do you have access to a preamp?

Thanks for your replies!
Yes I have preamps, I've tried patching in a Sound Skulptor MP73 to boost the level. I have uploaded some screen grabs here:
https://www.dropbox.com/gallery/937959/1/Laz%20EQN?h=e2241f
Which shows the test osc going out of Logic (in the red) and into Spectre on input one (via the EQN). In the first image I have a sine wave which looks something like yours on your journey thread, but then in the second I have upped the level from the preamp and I lose any recognisable sine wave shape.
Do the relative levels going out of Logic and into Spectre look right or is something very wrong? I still can't get RV5 to have any effect on the shape of the wave?
Title: Re: EQN build thread
Post by: ShandonSound on September 04, 2011, 01:53:29 PM
Also, when I plug a mic in to the preamp>EQN it sounds very thin. Suspect there is more to this than lack of calibration. I've checked transformer wiring, and cap polarity, any suggestions where I should look next?

Thanks!
Title: Re: EQN build thread
Post by: peter purpose on September 04, 2011, 03:27:45 PM
any suggestions where I should look next?

Thanks!

Nope.... I told you I was a rubbish trouble shooter.
What you could do is inject signal into the neg leg of c48 to rule out the output section.
Try the same (in to out) with each upright amp.
Title: Re: EQN build thread
Post by: canidoit on September 04, 2011, 07:23:51 PM
You are getting the same thing I was getting at the first part of my callibration in my journey. When I got the bottom clip on my oscilloscope, I would turn the RV4 until I lost the bottom clipping in the wave and it became a normal sine wave again. Then that is when I boosted my signal more using my preamp and got a top clipping where I was able to use RV5 to get clipping at the top and bottom evenly.

Do you have access to a preamp?

Thanks for your replies!
Yes I have preamps, I've tried patching in a Sound Skulptor MP73 to boost the level. I have uploaded some screen grabs here:
https://www.dropbox.com/gallery/937959/1/Laz%20EQN?h=e2241f
Which shows the test osc going out of Logic (in the red) and into Spectre on input one (via the EQN). In the first image I have a sine wave which looks something like yours on your journey thread, but then in the second I have upped the level from the preamp and I lose any recognisable sine wave shape.
Do the relative levels going out of Logic and into Spectre look right or is something very wrong? I still can't get RV5 to have any effect on the shape of the wave?
Title: Re: EQN build thread
Post by: ShandonSound on September 16, 2011, 11:36:31 AM
What you could do is inject signal into the neg leg of c48 to rule out the output section.
Try the same (in to out) with each upright amp.

Peter, I'm afraid I have no idea how I would go about injecting a signal!
Looks like I'm out of my depth, probably have been for some time actually, I've just been lucky and tenacious!
I strongly suspect it's a fault/mistake rather than calibration but I don't want to impose on anyone's good will any longer.
If there is anyone out there that might be able to help me fix this I would be very happy to pay for your time and expertise, or if anyone can suggest someone to help (preferably UK based) I would be glad if you would PM me.
Thanks for all the help you have tried to give, I shall have a crack at my second channel and see if that reveals anything about the first!
Title: Re: EQN build thread
Post by: peter purpose on September 16, 2011, 02:38:22 PM
Calibration is unimportant. You'll never drive the thing hard enough to clip it.
Put rv5 in the middle and forget it for now.
RV4 is a fader... match in to out.

Injecting a signal.....  you've been doing it already into the input... you're just putting it somewhere else.
Title: Re: EQN build thread
Post by: canidoit on September 16, 2011, 06:58:56 PM
What you could do is inject signal into the neg leg of c48 to rule out the output section.
Try the same (in to out) with each upright amp.

Peter, I'm afraid I have no idea how I would go about injecting a signal!
Looks like I'm out of my depth, probably have been for some time actually, I've just been lucky and tenacious!
I strongly suspect it's a fault/mistake rather than calibration but I don't want to impose on anyone's good will any longer.
If there is anyone out there that might be able to help me fix this I would be very happy to pay for your time and expertise, or if anyone can suggest someone to help (preferably UK based) I would be glad if you would PM me.
Thanks for all the help you have tried to give, I shall have a crack at my second channel and see if that reveals anything about the first!
I am presuming that injecting means the following. On an audio output of a TS output jack, there is the positive, which is the tip. I think it  means hooking that tip up to the leg of whatever? As for the sleeve of the TS output jack, I think you would connect that to where it usually be connect to, like the output sleev socket of the unit.

## before you do this, please wait for a confirmation from someone who knows more. I am just presuming here.  :)
Title: Re: EQN build thread
Post by: ShandonSound on September 17, 2011, 08:00:54 AM

I am presuming that injecting means the following. On an audio output of a TS output jack, there is the positive, which is the tip. I think it  means hooking that tip up to the leg of whatever? As for the sleeve of the TS output jack, I think you would connect that to where it usually be connect to, like the output sleev socket of the unit.

## before you do this, please wait for a confirmation from someone who knows more. I am just presuming here.  :)

I imagined it would be something along those lines, but like you was unsure. Nice to know I'm not the only one! :)

Thanks!
Title: Re: EQN build thread
Post by: peter purpose on September 17, 2011, 01:14:56 PM
(http://lazpro.com/testin.JPG)
Title: Re: EQN build thread
Post by: zayance on November 17, 2011, 12:43:10 PM
Hi Guys,

Lately i've been having some weird things with my EQN,
i had same things some time after building tem, and
recognised i had forgot to put one of the jumpers on the Output
transformer of one module, and had the both EQN's fitted apart in the rack afterwards,
so i tought that was resolved....

Anyway, today i have two EQN next to each other, and i noticed same weird
oscillation noises as before, in the high frequency region, most noticeable on attacks of percussive sounds...
So i said maybe transformer too close to each other since i don't remember having this
when a couple of slots away.
So i tried this again today, one in slot 1 and the other in slot 4 for example, (all other stuff out in there just the EQN's)
Weird oscillation noise reduced, but as soon as one of the modules is out, no more oscillation at all,
well maybe still but can't hear it then....and one out or the other, same same, i tought one would cause the other etc...
Seems it's not the case.
When back close together, the Noises get back....

Kind of weird and i'm a little unsure about the symptoms, the units work as suppose to tough.....
I'll try to flux clean all the board as i only did this on the opamps... (minor trooblshooting) And try again,
but i don't think it will be that easy.
And i'll push the testing a little more when i have some time this week end....

EDIT: And i'll record a sample of what i'm talking about...

But any toughts on why? And what i could check...


Thanks a lot
Title: Re: EQN build thread
Post by: zayance on November 17, 2011, 01:38:53 PM
Nah couldn't wait, took them out, fluxed cleaned, reheated some solder joints, reracked next to each other,
and seems it's gone huh, hope for good, time will tell, stupid gremlins....
Maybe some stress on the board taking them In/out  causing a small crackle somewhere or whatever,
i'll put this in the "mistery folder"......
Nevermind.
Title: Re: EQN build thread
Post by: dmp on November 17, 2011, 03:46:05 PM
I've had similar gremlins with my pair of EQNs. The noise is more like a quiet sputtering. It is very soft, but noticeable. It increases as the pots are turned up. It exists in all the bands, so it is on the input side of things. I replaced some of the pots and it didn't change it. And when I turn the pots the make noise, like there is DC across the pots.
I'll try cleaning the boards and see if that takes care of my problem as well.
Title: Re: EQN build thread
Post by: shabtek on November 18, 2011, 12:39:22 AM
are you using the dcdc converter or 51x
Title: Re: EQN build thread
Post by: zayance on November 18, 2011, 07:04:30 AM
Well at noon, i fitted back one gear at a time my stuff inside the rack, don't have a lot but still..
And noise got back, but it's when my Mixxbuzz is next to the EQN's, the Gremlins are there, when alone in the rack
it seems no prob...hmmm
I'm running 51X without DC/DC

Or it has nothing to do with this, and again some Gremlins back there, from fitting things back again as before...

hate those Gremlins.....


EDIT: After taking the Mixxbuzz out, the Gremlins were still present in the EQN's but went away
after Bypassing EQ bands and the unit tottaly, and playing with that, so maybe some leaking Caps in there?


@dmp: Going back in the thread, it seems you maybe got same parts as me concerning the ceramic and tantalum links i've posted some time ago reply#175
Maybe some bad tantalums we got?

Anyway will get more into it this week-end.
Title: Re: EQN build thread
Post by: dmp on November 18, 2011, 08:41:12 AM
I'm using 51x as well. A problem with a tant cap is a good idea. It seems like it could be a problem with DC not being blocked somewhere. Good luck and let me know what you find.
Title: Re: EQN build thread
Post by: peter purpose on November 19, 2011, 08:55:10 AM
I have no idea what's going on here boys.
Title: Re: EQN build thread
Post by: zayance on November 19, 2011, 10:37:14 AM
I have no idea what's going on here boys.

haha, me too, how comes? Will see tomorrow, today i had to repair my father's 1984 E30 BMW seat huh, what a PITA
nothing to do with EQN i know, i talk too much....
Title: Re: EQN build thread
Post by: dmp on November 19, 2011, 01:04:53 PM
Quote
@dmp: Going back in the thread, it seems you maybe got same parts as me concerning the ceramic and tantalum links i've posted some time ago reply#175
Maybe some bad tantalums we got?
I checked my records and I only ordered the same ceramics as you from digikey - the tants I got from mouser. Since the ceramics aren't polarized I doubt that is it.

Just looking now, I think I might have C48 backwards...
Title: Re: EQN build thread
Post by: zayance on November 20, 2011, 10:27:14 AM
Allright, so checked the unit with LAB PSU, and all seems in place, and right direction, no prob...
And there is no significant DC on pots nore in the circuit after most Caps,
All tantalums are ok etc.....

Anyway wanted to plug them back in the rack, as i was testing on LAB PSU
and to put a scope on the output and try to have a look of what's going on
after injecting different frequencys in there....
Plugged it back, with some other 500 stuff, and no weird sounds again...

Did i already mentioned i hated those Gremlins? Because i really hate them....


EDIT:
Sound is back , i have recorded it, get the same thing dmp?
One file is inside a percussive sound, it's more noticeable a little after in the file...
Second one is the sound alone, and i'm playin with it, the sound is the most noticeable when HF at 12Khz,
and volume of HF Band at a precise position BUT with the volume of Mid frequency up as well, in the file i'mplaying with the MF volume pot but with no frequency selected.
And playing with HF frequency also afterwards, and bypassing.....
For me seems it's an oscillation problem, now from where i don't know?

Right click save:

http://dl.dropbox.com/u/12562977/EQN%20Percussive.wav

http://dl.dropbox.com/u/12562977/EQN%20Noise.wav
Title: Re: EQN build thread
Post by: peter purpose on November 20, 2011, 12:57:54 PM
How very odd..... did you connect the giggling pin to the laughing shaft?
Title: Re: EQN build thread
Post by: zayance on November 20, 2011, 01:59:47 PM
not this week-end unfortunatly.....
Title: Re: EQN build thread
Post by: peter purpose on November 20, 2011, 03:42:20 PM
 :)
Title: Re: EQN build thread
Post by: zayance on November 20, 2011, 04:49:36 PM
Found on mnats Page:

Quote
I terminated the input to the EQN module with a smallish resistor I had lying around and listened again to the output. Even back in the 51X jig the noise was still there.

The noise didn't seem to change much regardless of frequency switch postitions. But it did, of course, disappear when the EQ IN switch was switched OUT.

Pulling out the BA284 amps one at a time saw the noise disappear. Having located the offending amplifier board I thought about what might be causing such a popcorn noise. After giving the board a good clean I removed the transistors and found there was one particularly noisy one. Problem solved.

Will try that....
Title: Re: EQN build thread
Post by: zayance on November 25, 2011, 07:36:59 AM
Allright, found the bad amp, changed the transistors on it (all the rest was ok), problem solved....
Title: Re: EQN build thread
Post by: peter purpose on November 25, 2011, 09:19:57 AM
Merveilleux
Title: Re: EQN build thread
Post by: zayance on November 25, 2011, 09:36:57 AM
flabbergasting
Title: Re: EQN build thread
Post by: mnats on November 25, 2011, 06:50:46 PM
Allright, found the bad amp, changed the transistors on it (all the rest was ok), problem solved....
flabbergasting

I wonder if there was a bad batch of these transistors? The coincidence is too weird that more than one and possibly three people have experienced a problem with them. dmp - what's the verdict?
Title: Re: EQN build thread
Post by: peter purpose on November 26, 2011, 10:30:45 AM
Sounds like it Mako.
Title: Re: EQN build thread
Post by: atticmike on November 26, 2011, 12:10:14 PM
can anybody tell me what the eq is based on?
Title: Re: EQN build thread
Post by: zayance on November 26, 2011, 12:46:28 PM
can anybody tell me what the eq is based on?

Brrr.. wrong question  :D
Title: Re: EQN build thread
Post by: atticmike on November 26, 2011, 12:54:46 PM
can anybody tell me what the eq is based on?

Brrr.. wrong question  :D

why's that ? :D
Title: Re: EQN build thread
Post by: peter purpose on November 26, 2011, 01:15:40 PM
Tony is just being mean.... it's based on a Massey Fergusson tractor.






Mike, it's a 1084/1073.
Title: Re: EQN build thread
Post by: 12volts on November 26, 2011, 01:22:24 PM
Mike, have you ever heard of Rupert Neve?

If you haven't ... oh dear ... here is the mess Webley, you know what to do.

Title: Re: EQN build thread
Post by: peter purpose on November 26, 2011, 01:57:38 PM
Wrong forum Frank..... check your alzheimers meds son.
Title: Re: EQN build thread
Post by: zayance on November 27, 2011, 06:17:45 AM
@atticmike: don't take all this too seriously, we're just bunch of kids haha...
Title: Re: EQN build thread
Post by: atticmike on November 27, 2011, 08:53:11 AM
That's okay, I should rather be ashamed of myself for not recognizing the magic behind this clone :D

Actually, I'm quite big on eqs but have never found an opportunity to get a hold of neves / try em out.

For the past weeks, the thing that has haunted me the most, ever since I got to work with e series ss eqs at a studio, are the x-rack e-series ssl classic eqs in black and brown.

I was hoping for a clone miming the e / g series ssl eq since this beauty is a king in any application, no matter whether it is kick, snare, guitar, vocals or strings.

What is the neve 1073's main application?
Title: Re: EQN build thread
Post by: zayance on November 27, 2011, 09:51:59 AM
Quote
What is the neve 1073's main application?

brrr...wrong question....next... haha.
Title: Re: EQN build thread
Post by: atticmike on November 27, 2011, 10:58:16 AM
Quote
What is the neve 1073's main application?

brrr...wrong question....next... haha.

Why don't you just fill me in or enlighten me on the path of neve eqs? :D
Title: Re: EQN build thread
Post by: zayance on November 27, 2011, 11:02:26 AM
Quote
What is the neve 1073's main application?

brrr...wrong question....next... haha.

Why don't you just fill me in or enlighten me on the path of neve eqs? :D

http://www.youtube.com/watch?v=HGxVr0Ti6uk
Title: Re: EQN build thread
Post by: Marcocet on January 07, 2012, 02:51:10 PM
Okay, I just built a new pair and I'm having a strange issue with them.

I'm getting +/-14 some volts to the DC-DC converter fine, but i'm only getting 5v out the other side. I've tried swapping them to no avail. Could it be an issue with Q1? Or am I missing something else?

Thanks!

EDIT: got it. Bad inductors again. You'd think I would have learned my lesson the first time. The slow start circuit wasn't opening all the way. (still isn't for that matter, but the eq seems to be running fine at about 20v)

Title: Re: EQN build thread
Post by: peter purpose on January 07, 2012, 06:20:25 PM
Could it be an issue with Q1?  QUITE POSSIBLY
Or am I missing something else? QUITE POSSIBLY
Title: Re: EQN build thread
Post by: Marcocet on January 07, 2012, 06:43:42 PM
Could it be an issue with Q1?  QUITE POSSIBLY
Or am I missing something else? QUITE POSSIBLY

Ladies and Gentleman, the ever helpful Mr. Peter Purpose!

I still love these things btw Peter. What're you working on next??
Title: Re: EQN build thread
Post by: peter purpose on January 07, 2012, 06:52:12 PM
Always glad to help Marc. 8)
500 series single space sta-level.
Title: Re: EQN build thread
Post by: Marcocet on January 07, 2012, 07:43:58 PM
Always glad to help Marc. 8)
500 series single space sta-level.

If you're serious put me down for two :)
I saw that 500 tube pre you did, and I wouldn't put it past you. Crazy thought though.
Title: Re: EQN build thread
Post by: dmp on January 10, 2012, 06:40:21 PM
Quote
I wonder if there was a bad batch of these transistors? The coincidence is too weird that more than one and possibly three people have experienced a problem with them. dmp - what's the verdict?

Confirmed - I had the same thing. Moving the amp boards from on EQN to the other I saw the level of the sputtering noise follow particular amp boards. I replaced the transistors on two amp boards and now my pair of EQNs are both quiet with absolutely no sputtering. The transistors I replaced had 'BK47' on them. I replaced them with code 'BB30'.
Title: Re: EQN build thread
Post by: Marcocet on January 12, 2012, 03:10:48 PM
Okay, here's a whole new ridiculous problem I can't figure out :)

The two modules I just built both work perfectly on the bench. However in my rack or console the signal is EXTREMELY quiet. It's not distorted, and the EQ appears to be working perfectly, but they're like 20db down. Any thoughts?

thanks as always

Title: Re: EQN build thread
Post by: jandoste on January 12, 2012, 04:40:34 PM
Okay, here's a whole new ridiculous problem I can't figure out :)

The two modules I just built both work perfectly on the bench. However in my rack or console the signal is EXTREMELY quiet. It's not distorted, and the EQ appears to be working perfectly, but they're like 20db down. Any thoughts?

thanks as always

Play with RV4 :) I had the same question :)
Title: Re: EQN build thread
Post by: Marcocet on January 12, 2012, 06:14:18 PM
Well it's not RV4. I had calibrated it to the input at home and it was fine, but I tried turning it all the way in either direction and the problem is still the same. Then I tried backing off RV5 but nothing happened there either.
Title: Re: EQN build thread
Post by: peter purpose on January 12, 2012, 08:13:30 PM
Have you tried these in a working slot on the desk?
Title: Re: EQN build thread
Post by: Marcocet on January 12, 2012, 11:04:31 PM
Have you tried these in a working slot on the desk?

pth:)

yes, tried them everywhere. They work fine with my bench supply, but zilch from my console or rack. I measured the racks voltage as 15.65, and I'm working with more like 14 at home, so I'll crank it up a bit and see if that changes anything.

Title: Re: EQN build thread
Post by: Marcocet on January 13, 2012, 01:19:08 PM
Nope, voltages were fine at home. Any other thoughts? What's really throwing me is the fact that BOTH of them aren't working in either the console OR the rack. There are other EQNs in both that are working fine.

Any thoughts at all would be greatly appreciated.
Title: Re: EQN build thread
Post by: peter purpose on January 14, 2012, 01:17:53 AM
Any thoughts at all would be greatly appreciated.

You're doing something wrong!

So they were both working in the rack, but having been put in the desk and retested in the rack... neither work at all?
Tis a conundrum for sure.

As has been said many times before, I'm no trouble shooter.
Have you used any parts in these new ones that you didn't in the working ones?
What voltage is the dc-dc converter putting out now?

I'm flummoxed.
Title: Re: EQN build thread
Post by: Marcocet on January 15, 2012, 06:43:17 PM
Not quite:

They're working perfectly on my bench with the bench power supply and with a +/-15v wall wart I've got. However when I take them to the studio and plug them in to either the rack or the desk they pass almost no signal (like 30 some db down). This happens in both the 500 series rack (Purple Sweet 10) and in the desk. My other EQN modules work perfectly in both the desk and rack.

Really confusing one.... but that's how they go. Thanks for the help Peter! Anybody else have any ideas?

EDIT Solved, I'm an idiot. Neutral side of transformer secondaries were reversed. Signal was canceling itself out :) I checked that first but missed it somehow...
Title: Re: EQN build thread
Post by: number2 on April 20, 2012, 08:33:08 AM
First of all, I take issue with your discriminatory policy against idiots.

2nd, will this work for c25?

http://www.mouser.com/Search/ProductDetail.aspx?R=MKS4D024702A00KSSDvirtualkey50520000virtualkey505-MKS4.047%2f100%2f10 (http://www.mouser.com/Search/ProductDetail.aspx?R=MKS4D024702A00KSSDvirtualkey50520000virtualkey505-MKS4.047%2f100%2f10)

Title: Re: EQN build thread
Post by: peter purpose on April 30, 2012, 11:57:12 AM
Sorry, I haven't been keeping an eye on this thread.
It'll work if the leads are long enough. As in the bom... you want a 10mm/0.4" lead spacing.

My policy stands and will be strictly enforced.
Title: Re: EQN build thread
Post by: number2 on May 08, 2012, 08:06:21 AM
well I'm related to some idiots and they're really nice people ;D

thanks bud
Title: Re: EQN build thread
Post by: number2 on May 12, 2012, 08:37:14 AM
http://au.mouser.com/ProductDetail/Diodes-Inc-Zetex/ZTX796A/?qs=%2f4dsY8i%2fUxIDKYU0UcTJ%2fFdTORtTHkvDu%252bKvCRzUrZk%3d

will this replace the bc184c that is obsolete?

I have a relative who is an idiot that wants to know
Title: Re: EQN build thread
Post by: peter purpose on May 12, 2012, 04:17:34 PM
will this replace the bc184c that is obsolete?

No idea, but try bc550c.
Title: Re: EQN build thread
Post by: number2 on June 01, 2012, 10:24:16 AM
anyone care to teach a lesson on transistor replacement?

I read that these are the important values to compare when substituting transistors. Any comments would be appreciated.
Does this table let me know that the bc550c is a good substitute for the bc184c? I trust that it is I just want to know why

(http://i47.tinypic.com/t675av.jpg)
Title: Re: EQN build thread
Post by: number2 on June 15, 2012, 03:59:09 PM
I'm not passing audio. what do I check first?
Title: Re: EQN build thread
Post by: peter purpose on June 16, 2012, 12:29:56 AM
I'm not passing audio. what do I check first?

Your signal generator.
Title: Re: EQN build thread
Post by: number2 on June 17, 2012, 05:03:20 PM
signal generator? I'm just plugging a mic into the lunchbox w/ EQN

audio goes in via the mic but doesn't come out

are there known multimeter voltage measurements I can check to find the problem?
Title: Re: EQN build thread
Post by: benlindell on June 17, 2012, 05:21:50 PM
There's your first problem right there. You need to connect a line level source to the EQN to test it, it's not a mic preamp.

signal generator? I'm just plugging a mic into the lunchbox w/ EQN

audio goes in via the mic but doesn't come out

are there known multimeter voltage measurements I can check to find the problem?
Title: Re: EQN build thread
Post by: number2 on June 18, 2012, 06:46:58 AM
Oh thanks bud

I had it going thru a preamp 1st but I guess not line level. I used the HiZ input and now it is working
Title: Re: EQN build thread
Post by: jrowell on August 07, 2012, 04:07:22 PM
Hello All,

This might be of interest to any builders of this kit.

I don't know if this has been addressed in a board revision, I did not find mention of it in the thread.

The board versions I have just completed for a client had a missing connection in the LF switch/BA205 card area. 

The symptom is LF response shelved below about 500 Hz, -1.8dB down, or so, with EQ in and all bands set to off.

If you are doing just mid or top EQ, this is a problem.

If the LF band is set to off, the response droops below 500Hz.

Since I am a vintage N*v-e service technician, I knew the issue would be in the off paths of the LF freq switch.

The offs go to one side of C29, a 10nF. The other end of C29 feeds the BA205 cap buss.

The pot wiper goes to one end of R10, a 12K. The other end of the 12K goes to C30 and to the LO/HI amp input.

The pot wiper is normally permanently connected to the off positions. It is not here.

The offs end of C29 and the wiper end of R10 are also normally connected together. Again, not here. This is pin L on an original BA205 board diagram.

Basically we have two pin L points. They need to be connected.

All this can be resolved by connecting the offs end of C29, (side nearest the switch) and the wiper end of R10, (the end closest to the inductor) together with a jumper wire.

Boom, no droop in LF with EQ in and LF set to off.

LF EQ at full cut or boost stays basically identical. Curve is maybe a tad more relaxed.

They actually are a bit flatter than an original, with this corrected.

There are some other details that we found, that improve things, but very excellent execution overall.

This one is a biggie, and I wanted to give something back to DIY. It has been good to me.

We have made a reputation of taking DIY based stuff and turning it into custom level builds, with excellent performance, and all inherent issues solved. 

The EQ is most impressive with the reasonably small number of inherent issues solved.

Thanks again, I hope this helps someone out.

James Rowell
Audio Systems Technician
Sound Service Electronics
www.ssevintageaudio.com

Ask about our 1176 Rev B w/ factory LN build.
Title: Re: EQN build thread
Post by: canidoit on August 07, 2012, 11:04:19 PM
Let me get this straight.

- If you put the EQ in and the Lo Freq set to off, there is a low frequency loss to the signal, even without doing any changes to the other knobs? Does this mean it changes how the curves react when adjusting the other frequencies?
- If you only use the mid and high end part of the eq, means users will encounter this issue? How about if you just leave the low shelf to "on" but the gain at 0, will there still be a problem?
- Can you please provide images and a diagram of the fix you describe?
- If you create a wire link that you mention, this will solve the problem?
- Applying this fix, does that mean you have to re-calibrate the unit again?
- Are there any other issues with this unit and if so, what is the fix?

Thanks
Hello All,

This might be of interest to any builders of this kit.

I don't know if this has been addressed in a board revision, I did not find mention of it in the thread.

The board versions I have just completed for a client had a missing connection in the LF switch/BA205 card area. 

The symptom is LF response shelved below about 500 Hz, -1.8dB down, or so, with EQ in and all bands set to off.

If you are doing just mid or top EQ, this is a problem.

If the LF band is set to off, the response droops below 500Hz.

Since I am a vintage N*v-e service technician, I knew the issue would be in the off paths of the LF freq switch.

The offs go to one side of C29, a 10nF. The other end of C29 feeds the BA205 cap buss.

The pot wiper goes to one end of R10, a 12K. The other end of the 12K goes to C30 and to the LO/HI amp input.

The pot wiper is normally permanently connected to the off positions. It is not here.

The offs end of C29 and the wiper end of R10 are also normally connected together. Again, not here. This is pin L on an original BA205 board diagram.

Basically we have two pin L points. They need to be connected.

All this can be resolved by connecting the offs end of C29, (side nearest the switch) and the wiper end of R10, (the end closest to the inductor) together with a jumper wire.

Boom, no droop in LF with EQ in and LF set to off.

LF EQ at full cut or boost stays basically identical. Curve is maybe a tad more relaxed.

They actually are a bit flatter than an original, with this corrected.

There are some other details that we found, that improve things, but very excellent execution overall.

This one is a biggie, and I wanted to give something back to DIY. It has been good to me.

We have made a reputation of taking DIY based stuff and turning it into custom level builds, with excellent performance, and all inherent issues solved. 

The EQ is most impressive with the reasonably small number of inherent issues solved.

Thanks again, I hope this helps someone out.

James Rowell
Audio Systems Technician
Sound Service Electronics
www.ssevintageaudio.com

Ask about our 1176 Rev B w/ factory LN build.
Title: Re: EQN build thread
Post by: jrowell on August 08, 2012, 12:44:17 AM
Okay,

Yes. Yes.
Yes. Yes.

If you put the EQ in, and all switches to OFF, and do a freq sweep plot you should see it very obviously.

Original N* modules have a bit of passband ripple (more like a very gradual wave) with the EQ in, but not nearly that much, maybe 0.5dB. It depends on how much is wrong with the module. There is something wrong with almost all of them.

Tracing out the points from the description I have provided will take you about 2 min, it will take me 20 to snap and photoshop pics and post them. The points are quite easy to find, the LF pot wiper only goes to the correct end of the 12K R10. The correct end of C29 is the only thing attached to one of the LF switch points.

Yes, one wire link solves the issue. Unfortunately you will not be able to do it from the top of the board.

Make sure this hasn't been caught in a board rev. Measure the points first. They should be 0 ohm. Power OFF. Not any other than 0 ohm. If not do the link.

You should have calibrated in bypass, so if so no.

There are some other items of interest, I think that my client that paid a premium for me do do these my way might be annoyed if I give away much more.

This was a big one, that really affects the performance of the unit, so I don't mind sharing it. Besides, it is a missing connection on this project, not a N* thing that can be applied to other modules that I service.

The others are N*v-e tidbit stuff that I do hold close.

Just one, most all Neve Class A modules, and all clones I am aware of are biased wrong.

That is the most critical setting ever in history in terms of the effect on tone, and it is the main reason people complain of 'pointy N*v-e'

I never got that 'pointy N*v-e' thing until I started getting in more working modules that had been set wrong, over the last number of years, it is a big issue.

That is a service I offer, to original modules. Clones usually need modding to bias correctly, so unless the extra work is discussed and understood, I wouldn't be doing those.

I do need to cover my time with billable work, and I do have to respect my clients needs with current ongoing projects, so I must return to soldering and the AP.

Thanks guys,

James

Let me get this straight.

- If you put the EQ in and the Lo Freq set to off, there is a low frequency loss to the signal, even without doing any changes to the other knobs? Does this mean it changes how the curves react when adjusting the other frequencies?
- If you only use the mid and high end part of the eq, means users will encounter this issue? How about if you just leave the low shelf to "on" but the gain at 0, will there still be a problem?
- Can you please provide images and a diagram of the fix you describe?
- If you create a wire link that you mention, this will solve the problem?
- Applying this fix, does that mean you have to re-calibrate the unit again?
- Are there any other issues with this unit and if so, what is the fix?

Thanks
Hello All,

This might be of interest to any builders of this kit.

I don't know if this has been addressed in a board revision, I did not find mention of it in the thread.

The board versions I have just completed for a client had a missing connection in the LF switch/BA205 card area. 

The symptom is LF response shelved below about 500 Hz, -1.8dB down, or so, with EQ in and all bands set to off.

If you are doing just mid or top EQ, this is a problem.

If the LF band is set to off, the response droops below 500Hz.

Since I am a vintage N*v-e service technician, I knew the issue would be in the off paths of the LF freq switch.

The offs go to one side of C29, a 10nF. The other end of C29 feeds the BA205 cap buss.

The pot wiper goes to one end of R10, a 12K. The other end of the 12K goes to C30 and to the LO/HI amp input.

The pot wiper is normally permanently connected to the off positions. It is not here.

The offs end of C29 and the wiper end of R10 are also normally connected together. Again, not here. This is pin L on an original BA205 board diagram.

Basically we have two pin L points. They need to be connected.

All this can be resolved by connecting the offs end of C29, (side nearest the switch) and the wiper end of R10, (the end closest to the inductor) together with a jumper wire.

Boom, no droop in LF with EQ in and LF set to off.

LF EQ at full cut or boost stays basically identical. Curve is maybe a tad more relaxed.

They actually are a bit flatter than an original, with this corrected.

There are some other details that we found, that improve things, but very excellent execution overall.

This one is a biggie, and I wanted to give something back to DIY. It has been good to me.

We have made a reputation of taking DIY based stuff and turning it into custom level builds, with excellent performance, and all inherent issues solved. 

The EQ is most impressive with the reasonably small number of inherent issues solved.

Thanks again, I hope this helps someone out.

James Rowell
Audio Systems Technician
Sound Service Electronics
www.ssevintageaudio.com

Ask about our 1176 Rev B w/ factory LN build.
Title: Re: EQN build thread
Post by: Marcocet on August 08, 2012, 12:56:45 AM
Interesting. I hadn't noticed it but I'm going to take a closer look now. Thanks for the tip!

Title: Re: EQN build thread
Post by: jensenmann on August 08, 2012, 02:55:40 AM
James, thanks a lot for your hint.
Title: Re: EQN build thread
Post by: peter purpose on August 08, 2012, 08:02:15 AM
James,
Thanks for pointing that out.

canidoit... leave the man alone.... he has said he's busy.
No revisions address anything but transformer connections.

None of us noticed anything lacking, so make your own mind up about pulling your modules apart.
Title: Re: EQN build thread
Post by: jrowell on August 08, 2012, 11:51:14 AM
Hey no prob guys, I looked for a board version number, but couldn't find one.... It sounds like Peter has said the only revs involved TX stuff...

I know these are early ones, this was a closet project as the client did other things first.

As far as subjective, it is a big difference, so I would do it, personally. Everything can be taken as subjective, since it all affects tone. Correct is different. This is a subjective tone change caused by an incorrect wiring. That would be something other than subjective.

Canidoit, simple test. Run full mix through. Something with a nice full tight low. EQ Out. Listen, all switches OFF. Pot settings don't matter. Switch the EQ in. The low mid on down should drop noticeably. 

If so do the jump as described. As soon as you see the bottom of the boards you will see the points I am talking about right away from the description. They are easy ones to find, in this case.

Your map of the 51X PSU came in handy as I did a custom build one for this same client. 

I might get a chance to post an AP plot later on, before and after.

Thanks again guys,

James
Title: Re: EQN build thread
Post by: jrowell on August 08, 2012, 12:10:09 PM
Oh yes, certainly nothing lacking overall.

Issue is only there when LF band is OFF. It did show with an LF freq selected, and not cut or boost. It did not affect full cut or boost. I did not check medium amounts of cut/boost. Logic says it would change things. Fixing the issue did change the shape at full boost, just a bit.

Not having that connection does change the filter arrangement in the LF. Period.

So usually not going to show up, under normal use, unless you use the other bands only, and follow good practice and switch unused bands off.

Or you are a nerd like me and do freq plots on an EQ in, with no frequencies selected, to see how close to bypass the response is.

You could hear it big time anyways. There wasn't a need to really plot it.

There is no real way to make up the difference, as there is no filter in the EQ to invert the curve.

My other tweaks were pretty small things.

As I said, for line in EQ only, this is superior to the original.

Lower distortion
Lower noise
Higher Input Headroom
Simpler Signal Path
More Frequencies
More Flexible Sound

Outstanding Peter,

James
Title: Re: EQN build thread
Post by: jrowell on August 09, 2012, 12:37:46 AM
Nope.

That would be the filter switch.

Reread the posts, I have described the points in there. You will have to use the layout on the first page of this thread, as your designators will be covered with components.

Deep in an amp, so will post plot and pic tomm


James
Title: Re: EQN build thread
Post by: jrowell on August 09, 2012, 12:43:37 AM
You got the non switch end right. The 12K end is correct.

James
Title: Re: EQN build thread
Post by: jrowell on August 09, 2012, 12:57:02 AM
The correct link is labeled in green.

James
Title: Re: EQN build thread
Post by: canidoit on August 09, 2012, 01:14:12 AM
Thanks James for fixing up the diagram!

I am very much considering doing this fix, but I just need some assurance before taking up some down time. Hopefully someone with more electronic experience than me and a regular here can confirm your fix and findings.
Title: Re: EQN build thread
Post by: jrowell on August 10, 2012, 08:44:53 AM
No problem. I might be able to get a plot up today.

I would like some confirmation as well, if it is every card out there.

Perhaps someone with some raw cards could see if those two points are connected on theirs,

If we think it though we can probably check from the top of the card, without having to take things apart.

A simple resistance test will show it. Those two points need to be connected.

I have serviced hundreds of N*v-e modules over the last 15 years. I know what they are supposed to sound like, in all modes of operation, and condition. The first audio test of these lasted 2 seconds, because I knew something was wrong. I make a point of listening before testing.

1.8dB down below 500Hz as a shelf is highly audible. Setup a comparison test, as I have previously outlined, and you will hear it, if it is there. Trust your ears.

I located a missing connection that exactly coordinated with the symptom.

When I installed the connection, the symptom went away, and the performance returned to correct N*v-e specification, in all modes. That would suggest a correct methodology and result.

Unless this has been caught in a board rev, or I got two bad boards (very unlikely) it is safe to say they all do it.

Switching bands off cleans up the sound. It is just good practice. So I always start out that way. That is why I noticed it immediately.

That is why N*v-e's don't use center detent pots. Center is never center on detents, so use a normal pot, and switch the EQ band off if you are not using it.

James
Title: Re: EQN build thread
Post by: whomper on August 12, 2012, 11:39:09 AM
Hey,

Starting my build and am in the process of sourcing parts. Anyone have a source for the 4m7 minis?

Could only locate 4m75 mini on Mouser, will they work just as well?
Title: Re: EQN build thread
Post by: jrowell on August 12, 2012, 11:13:08 PM
Whomper,

Could you measure your cards on resistance between the LF pot wiper end of R10, and the LF switch end of C29?

Tell us what you get?

The 4M75 will work fine.

Any value from 4M7 to 10M will work there.

I like 4M7.

I will get you a part number for the 4M7 (likely cheaper)

Check those points for me.

Thanks,

James
Title: Re: EQN build thread
Post by: peter purpose on August 13, 2012, 07:23:25 AM
RS 136-115P
Title: Re: EQN build thread
Post by: whomper on August 13, 2012, 12:31:56 PM
Whomper,

Could you measure your cards on resistance between the LF pot wiper end of R10, and the LF switch end of C29?

Tell us what you get?

James,

Will be happy to, but my board is only 15% populated. Which components do you require on board for that test? Am looking to get a Mouser order in a matter of two weeks or so.

Thanks James and Peter for the part number.
Title: Re: EQN build thread
Post by: jrowell on August 13, 2012, 02:45:16 PM
Any amount of components will do...

Checking the PN now,

James
Title: Re: EQN build thread
Post by: jrowell on August 13, 2012, 04:03:23 PM
 Mouser 660-CFS1/4CT52R475J for the mini 4M7.

These work well too, and we were getting the pots from there, so...

James
Title: Re: EQN build thread
Post by: whomper on August 14, 2012, 04:01:25 PM
Any amount of components will do...

Well, checked resistance between the two spots (R10 and C29) and it reads nothing. Perhaps since there is little components in that path at the moment. Not sure if it means anything...

EDIT: just to be clear, no continuity.
Title: Re: EQN build thread
Post by: dmp on August 15, 2012, 10:26:00 AM
jrowell, Thanks for sharing your findings on this!
This is why DIY is great.
The explanation makes sense looking at the schematics. I wouldn't hesitate to make this mod if the test points of R10 and C29 do not show continuity.
Here are the schems for anyone curious to see what he's talking about.
The left side shows the 1081 schematic with the BA205 LF module. The pot wiper is connecting to 'L' and the off positions of the switch. On the right is the BA205 schematic, showing the 'L' connection going to both the 12k (R10) and 10N (C29). Making this connection is the jrowell fix.

Now, why didn't I see this when I swept all the frequency bands in RMAA when I built my pair? Thanks again.
Title: Re: EQN build thread
Post by: jrowell on August 20, 2012, 02:42:06 AM
Thanks so much, it is no problem.

Yes those points should be joined.

The board layout stock feeds the wiper to the 12K and the offs to the 10N.

This creates two point 'L' s on the schem.

They need to be joined. As do the one end of the 10N and the 12K.

DMP, unless you swept the LF band on off, it wouldn't show.

It should have shown on the other band sweeps, if you returned the LF to off.

James
Title: Re: EQN build thread
Post by: Beeswax on September 15, 2012, 10:30:10 PM
Chaps - I've finished and calibrated accurately but experiencing a persistant wheezing, buzzing noise in the lunchbox.  Still present with the amp boards out.  Thoughts?
Title: Re: EQN build thread
Post by: peter purpose on September 16, 2012, 11:51:29 AM
If in the last slot next to the power supply, try moving it.
If it persists I have no idea.
Title: Re: EQN build thread
Post by: dandeurloo on October 25, 2012, 09:18:59 PM
I have noticed the low end roll off form the beginning.  I always thought I did something wrong that I could not track down.  I am gonna try James mod.  It seems very simple to do a nice 20 min fix!  I will report back. 
Title: Re: EQN build thread
Post by: haima on October 25, 2012, 09:27:29 PM
Chaps - I've finished and calibrated accurately but experiencing a persistant wheezing, buzzing noise in the lunchbox.  Still present with the amp boards out.  Thoughts?

Perhaps some kind of missing ground connection? Maybe double check your transformer wiring? wiring to the pots? etc

Have you tried the EQN with all the other modules in the lunchbox removed? Maybe you've exceeded the current supply of the lunchbox?

Title: Re: EQN build thread
Post by: dandeurloo on October 25, 2012, 10:55:38 PM
The mod fixed!  Thanks James great catch. 
Title: Re: EQN build thread
Post by: qmp audio on October 26, 2012, 01:13:17 AM
The mod fixed!  Thanks James great catch.

I'm almost complete w/ my first pair of these ( just need to do wiring ).   I did also test continuity between (R10 and C29) and was null before i started the build.  So, just to be clear,  the mod is simply one wire between those two points?
Title: Re: EQN build thread
Post by: dandeurloo on October 26, 2012, 01:20:49 AM
yep, super easy.
Title: Re: EQN build thread
Post by: jrowell on October 28, 2012, 03:17:16 AM
Thanks so much Dan for your confirmation and assistance to other members.
I am happy that it seems to be working so well.

Thanks again guys,

James Rowell
Sound Service Electronics 
Title: Re: EQN build thread
Post by: canidoit on November 01, 2012, 05:49:42 PM
yep, super easy.
So Dan, are you saying jrowell's mod fixed your low end issue with your build??
Title: Re: EQN build thread
Post by: dandeurloo on November 01, 2012, 10:52:10 PM
yes
Title: Re: EQN build thread
Post by: jrowell on November 11, 2012, 02:35:11 PM
Hi Guys,

We should probably stop calling it a mod.

That implies we are changing something to overcome an inherent deficiency.

This is a missing connection fix. We are putting in something that should be there and is on originals.

Very complex to put all this in a 500 format and I have worked in lots of big console modules that have a lot of cut traces and forests of jumpers from the factory.

Even the big N.

Let's call it 'the James fix'

Cheers guys,

James  Rowell

Sound Service Electronics
Title: Re: EQN build thread
Post by: canidoit on November 24, 2012, 07:06:56 AM
The mod fixed!  Thanks James great catch.
Dan, did you have to re-calibrate your unit??

When you calibrated your unit originally, did you do the normal calibration process that Peter mentioned prior to doing the mod. I wanna know if you followed Peter's original calibration, cause I did, and if you did not have to re-calibrate your unit after doing the mod, then I would not have to either : )

Thanks mate
Title: Re: EQN build thread
Post by: dandeurloo on November 24, 2012, 10:51:05 AM
No I didn't re cal it.  It really is a 10 min fix.  It takes more time to take the knobs off then anything else.

Title: Re: EQN build thread
Post by: whomper on December 14, 2012, 11:29:29 AM
Am missing 1-2 BC184 for TR1 and TR2. has anyone replaced them successfully with modern components? Will a BC547/549/550C work there?
Have two of those, first one complete BC184. If I want to use them in a pair, will it make a difference that one might have a replacement tranny?
Title: Re: EQN build thread
Post by: jplebre on December 16, 2012, 04:30:24 PM
Man, this one is a pretty fun build!

Quick question, on Mnats notes, he wired the screen to the carnhill screw.
I am not using a bracket, instead, mounting directly on the PCB (2 screws provided). The screw socket tests continuity to the goldfinger, so does the "SCREEN" PCB hole. The screws all measure continuity. However, soldering a piece of hardwire to the  pin and then stick it under the screw I can't get continuity.

Am I being daft (eg you need to solder to the screw as well?) or should I just go the old way (pin 6 to "screen" PCB point?)

Cheers
Title: Re: EQN build thread
Post by: jplebre on December 22, 2012, 05:17:36 PM
Hey guys just trying to understand this build a bit more, other than just sticking some solder blobs on a pcb:

- the 4.7M resistors are only there to avoid popping when swapping the resistors?
- The 620ohm resistor on a jumper, is this to emulate a o/p load?
- the jumper will allow 24v through for supply, but what happens where there's the 2 voltages present?
- any good source places for information on this kind of equalizer topology? I'm really not following how the whole Q (resistor divider before the amp) affects the signal

Tell me to shut up if I'm being silly. I did get most of the power section from the discussions about the TDK lambda on the old thread (using it the other way around).

Can you say that the input is a passive design with Class A o/p?

Tell me to shut up if I'm being to annoying. :)

:Guinness:
Title: Re: EQN build thread
Post by: peter purpose on December 28, 2012, 11:39:47 PM
Shut up.... you're being really forgen annoying.

1 As far as I know... yes.
2 Yes
3 You'll either add the components for +&- 16v, or leave them out for 24v. Jumping for 24v when using dc-dc converter will result in death.
4 NFI
Title: Re: EQN build thread
Post by: jplebre on December 29, 2012, 02:05:24 PM
This explains why I had to put the kits airing outside :P

(http://lazpro.com/benchmess.jpg)

Sorry for the hijack! back on thread... carry on
Title: Re: EQN build thread
Post by: dandeurloo on December 29, 2012, 02:19:10 PM
Where did you get your knobs?  I wouldn't mind getting enough for my pair.
Title: Re: EQN build thread
Post by: jplebre on December 29, 2012, 03:24:59 PM
those are something that Peter made for his stuff he said he wasn't selling them as they were for the finished units he was selling.
Not sure if it's still the case.

I'm using the skirted Kilo for the frequency and the normal Kilo with a line for the boost/cut. Pretty sweet! :)
Title: Re: EQN build thread
Post by: jplebre on December 31, 2012, 02:29:09 PM
Finished mine. Gorgeous! will callibrate it when I finish the second unit in 2013 :)

Happy new year y'all!
Title: Re: EQN build thread
Post by: whomper on January 01, 2013, 12:08:48 PM
Finished my second one! Calibrated both to the level and applied throw freq mod. Sound amazing!
Title: Re: EQN build thread
Post by: canidoit on January 02, 2013, 02:36:43 AM
Finished my second one! Calibrated both to the level and applied throw freq mod. Sound amazing!
What is the throw frequency mod?
Title: Re: EQN build thread
Post by: whomper on January 02, 2013, 05:43:11 AM
Finished my second one! Calibrated both to the level and applied throw freq mod. Sound amazing!
What is the throw frequency mod?

LOL

Lesson #7 - When typing from iPad, make sure to read what it will send over when you click submit...   :-[
I meant to say the Low Frequency mod.
Title: Re: EQN build thread
Post by: jplebre on January 02, 2013, 05:24:12 PM
the James Fix? :)
Title: Re: EQN build thread
Post by: jplebre on January 06, 2013, 04:04:07 PM
Finished 2 units. Ran them phase opposite and they are super tight! they begin to drift at 7kHz.
Hopefully will put them against n$$e reissues some time soon.

Pete made these too easy to build! :P

Question: my 51x is not running the 24v rail atm.
I have populated the parts for VPR 500 and am running of 16v no problems. Jumper is not in

When I finish the PSU supply, do I have to saw off the tab with the above configuration?

And - if needed in future - is taking out the TDK lambda and putting a jumper enough to go 51x 24v or do I need to remove further components?
Title: Re: EQN build thread
Post by: peter purpose on January 10, 2013, 03:48:39 AM
Joao,
If you saw off the 24v tab, you can ONLY run it off the 16v rails.
Title: Re: EQN build thread
Post by: jplebre on January 10, 2013, 10:45:46 AM
I haven't yet, as I don't have +-24v rails yet running on my 51x. My question is do I have to? :)
(I have populated all the VPR 16v bits)

Was hoping I could swap it in case I run out of 16v juice at home or I need to go somewhere by removing the lambda and putting the jumper in.
Title: Re: EQN build thread
Post by: peter purpose on January 10, 2013, 11:01:45 AM
Removing the dc-dc converter and putting in the jumper is fine for 24v operation. The other components will be happy going nowhere.
But as soon as the 24v tab is removed, you'll only be able to run it off the 16v rails.
Leaving the tab on... without the jumper inserted is fine for 16v.
Title: Re: EQN build thread
Post by: jplebre on January 10, 2013, 11:40:17 AM
AWesome! Interchangeable between the 2 alliances! you are a genius! thanks!
Title: Re: EQN build thread
Post by: scott_humphrey on February 05, 2013, 09:36:16 PM
It's been a cold, blustery winter, with dreams of multiple channels of Neve-style EQ swirling through the frosty air….

I finished 10 units the other week, and I just wanted to say thanks to Peter for making this possible. All units seem to work just fine. I haven't calibrated yet, but using them on a mix they all seem to do what they are supposed to do. Also, thanks to Mnats and canidoit for sharing their advice.

Speaking of sharing, I'll fess up to the stupid mistake that I made and tell you how I solved it. I ended up soldering the Q switch and the bypass switch to the wrong side of the board--and I repeated this mistake on each of the 10 boards! These switches are difficult to removed because the pins are a tight fit in the board even without solder, and I was really worried about damaging the circuit boards during the removal process. After some research, I ended up ordering the Quick Chip SMD-1 removal kit from eBay. I won't go into the details of the product, but for removing a part with multiple pins this worked great and none of the boards were damaged. Despite this, the plastic housing on some of the switches was damaged by the combination of heat and the mechanical force of having to pull them from the board with pliers.  I ordered replacement switches (Multicomp p/n 9473017) and all is well.

Another tip: mnats describes drilling holes so that the potentiometers will seat correctly. I was too lazy for this, and decided instead to clip the tabs off of the potentiometers. I then used the pliers to roughen (make small, superficial cuts in) the remaining metal that interfaces with the bracket, so it acts like a lock washer. This worked very well.

10 years ago I never would have dreamed it possible to own some of the equipment that I now have because of groupdiy. Thanks and cheers!
Title: Re: EQN build thread
Post by: jplebre on February 06, 2013, 06:39:45 AM
Scott, I hear you!

Since I completed my 2 channels they have been used strapped permanently on vocals and I've had to bounce some OH and pianos through it.
They are still expensive to build but what a treat!

Thanks for the tip on the SMD removal
Title: Re: EQN build thread
Post by: pachi2007 on February 06, 2013, 12:31:20 PM
Hi. I was looking at those awesome pictures  and now Ive got a doubt about the input trafo.
Those two screws for holding it to the pcb... can they go all the way inside the trafo or is there a risk to short it inside?.
Thx a lot
Pachi
Title: Re: EQN build thread
Post by: peter purpose on February 06, 2013, 05:08:24 PM
If you have to force it.... don't.
File them down, or pack them out.
Title: Re: EQN build thread
Post by: pachi2007 on February 06, 2013, 06:57:43 PM
Thx Peter.
I see some guys cut the screw, others put a nut and washer to gain some space to avoid cutting. My doubt was if there was a specific max to go inside the trafo before touching the core.
Doubt clear
Title: Re: EQN build thread
Post by: pachi2007 on February 10, 2013, 07:08:16 AM
Ok trouble here.

I´ve got one eq working first try,the other it´s not working fine.

I lose 12db FS when I insert the eq in Protools with the eq bypassed.
With the eq on I can recover the 12db drop with the trimmer.

I checked trafos wiring and seems ok. (I guess they should be ok otherwise I couldn´t recover gain with trimmer, am I right?)

I put a new clipping adj trimmer RV5 and same gain drop.

I noticed that the TR1/MJE3055 and the 47R/2w resistor don´t get warm even after 30min. Checked/resoldered all parts around and nothing.

MJE voltages left to right looking from the front: 1.6V, 23.39V,1.004V
The other working eq  voltages are: 2.17V, 23.14V, 1.571V (is this little bit higher a clue? ) Also this working one gets warm to touch after 5min or so.

Any advice would be apreciated.
Thx
Pachi

 
Title: Re: EQN build thread
Post by: jplebre on February 10, 2013, 09:05:34 AM
If you recover with EQ on, did you check polarity of the 22uF cap and value of 39k resistor to ground on the bypass path?
The o/p trimmer should affect both paths (RV5) (bypassed and EQ'd)

What value did you throw in on R29?

You are sure that your connections are ok? :)

Trying to help didn't have to do any troubleshooting with mine and want to understand the design a bit more

Title: Re: EQN build thread
Post by: pachi2007 on February 10, 2013, 09:48:55 AM

Thanks for you help Jplebre.
Yes I checked both 22uf tant caps, both 39k and the 3k3 next to it.

I didn´t explained myself clearly about RV4. It works both with eq on and bypass. When eq is on and all bands at their off position I can set the trim at unity gain, but when I turn the eq to off there´s this 12db drop.
With the eq on in fact I can go up to a -4db drop (almost there)  but if I bypass then the output is 12db hotter than the input.
I hope this makes sense.

R29 is 680R on both eqs. Works ok on the other eq. The thing that pisses me of is the heat thing at the 2w resistor and the big transistor. It gets warm on the working eq, not on this one, that´s why I was looking over there.

RV4 is for in/out gain adjustment and RV5 just for clipping adj right?

Thx a lot

Title: Re: EQN build thread
Post by: pachi2007 on February 10, 2013, 10:05:49 AM
"With the eq on in fact I can go up to a -4db drop (almost there)  but if I bypass then the output is 12db hotter than the input. "

Sorry I meant the other way around. -4db eq off then +12db hotter than input with eq on
Title: Re: EQN build thread
Post by: pachi2007 on February 10, 2013, 10:45:16 AM
Reheated some stuff , rechecked values, played with the RV5 trimmer and now R32 (the 2w 47R) gets hot as hell in a few seconds. Had 2 turn off power as it was too hot to touch. I see no solder bridges though.
Time for a cigarette  :)
Title: Re: EQN build thread
Post by: pachi2007 on February 10, 2013, 11:04:35 AM
Back from cigarette.
Turned RV5 trimmer the other way again, heat is gone.
I can hear some laughs from the pros :-)
Title: Re: EQN build thread
Post by: jplebre on February 10, 2013, 02:11:51 PM
so it was RV5 :)
Title: Re: EQN build thread
Post by: pachi2007 on February 10, 2013, 04:55:02 PM
No , still the same volume drop. I was just laughing at my troubleshooting and guessing :-)
I´m not sure what to do next. I guess I´ll start taking voltage readings with the working one and compare. I dont want to start swaping things without knowing, just because.
I also checked ground continuity around the input trafo and some other random points (beep beep) I don´t really know if is ok to touch it with the 9V of the multimeter, maybe it´s wrong.
Still slowly learning  ;)
Thx for asking
Title: Re: EQN build thread
Post by: jplebre on February 10, 2013, 05:59:25 PM
well, if i get it correctly RV5 will bias the signal so will raise the DC. The resistor next to it will be dissipating a fair amount of current (12v/47r) roughly 3w (if i get it right)

Since your voltage rails measure fine, I would say the issue is in the bypass circuit or on the BA283 amp http://pds2.exblog.jp/pds/1/201202/15/96/f0039496_2356277.jpg
Title: Re: EQN build thread
Post by: pachi2007 on February 11, 2013, 05:16:31 AM
Thx a lot jplebre.
I´ll report back with my findings
Title: Re: EQN build thread
Post by: pachi2007 on February 12, 2013, 05:27:12 AM
Hey Jp have you ever noticed how much brown and red look alike in those resistor lines?  :D

This is a little embarrasing. As you suggested first it was a resistor (33k instead of 3k3) at the bypass. I checked again all those values and there it was.
Anyway, it´s ok now, no level drop.
Thanks a million for your help, I owe u one.
Title: Re: EQN build thread
Post by: jplebre on February 12, 2013, 09:13:49 AM
Quote
Hey Jp have you ever noticed how much brown and red look alike in those resistor lines? 

all the time. I'm such a nerd now that I always turn them left - right, Up - down :P takes longer but makes it easier!

Cheers!
Title: Re: EQN build thread
Post by: duantro on April 20, 2013, 11:50:42 PM
Finished the pair up today. They worked and sound great! ...well after I realized I forgot the 24V jumper for my 51x juice! Thanks Peter for such an awesome project that is so easy to build.
Title: Re: EQN build thread
Post by: jplebre on April 21, 2013, 05:25:07 AM
Looking great. Loads of trident stuff you got there
Title: Re: EQN build thread
Post by: duantro on April 21, 2013, 10:40:14 AM
Looking great. Loads of trident stuff you got there
Yeah, 4 channels of the s80 tridents. I really like them. I'm also realizing that I'm a lazpro poster child. 3 api 525's, 2 la3a's, and now a pair of eqn's. I really like Peter's offerings as well.
Title: Re: EQN build thread
Post by: jplebre on April 21, 2013, 01:05:36 PM
I have the new 525's and they rock hard. :)
Title: Re: EQN build thread
Post by: duantro on May 04, 2013, 04:02:35 PM
Ok, calibration was pretty straight forward. I use one for a vocal mic and man they sound good! I like them so much that I grabbed another pair from the black market, so that I can have 4, to mate with my 80 series pres.  ;D
Title: Re: EQN build thread
Post by: Bassniac on October 08, 2013, 04:31:04 PM
Hi folks.

I am quite new at the DIY Buisiness. Until now I sucessfully build 6 DonClassic NV 73 preamps and love their sound and one EQN.
The second one will not work.

Until now I figured out that the problem must be located in the Output Amplifier Section. I reheated all the solder points and checked for Solder bridges. Furthermore I replaced all the Transistors TR1/TR2/TR3 with brand new ones. Instead of 184Cs I use 549s. In my second and working unit there are the same Transistors, no problem so far.
I hooked up the module to a 24V PS and get about 23,6 V at the Opamp 24V points, thats exactly as much as my PS supllies. Same at R27. At the EAs Primary I measure 18 V as well as at R35. At the Transistors I measure almost nothing and TR3 doesnt get anything as it is not getting warm. But the EA Tranny will heat up quite fast and that doesnt happen at my working unit. I got Petes schematics and the BA283 schematics from the original Neve 1073 manual and the one that was adapted to Petes EQN and was posted here somewhere. The Resistors seem to be right as I opticalle compared them to my working unit. The Caps look fine and the polar ones are installed the correct way.

Perhaps some more experienced troubleshooter could give me any hint at what I should look next.

Greets, Mathias
Title: Re: EQN build thread
Post by: jplebre on October 09, 2013, 03:46:02 AM
Quote
The second one will not work.
what exactly is happening (or not happening)?
no sound, distortion? crackling sounds? hum? sound passes but no eq?
Title: Re: EQN build thread
Post by: Bassniac on October 09, 2013, 03:53:07 AM
Exactly nothing is happening. No sound passes through. Only the EA Output Trany heats up. The unit seems to short the power line as even my preamps wont work if installed into the 51x rack with the EQN.

Cheers
Title: Re: EQN build thread
Post by: Bassniac on October 09, 2013, 09:56:23 AM
I think I got it and narrowed down the problem to the EA 1166.
The primary windings are short to the Chassis of the Transformer and the chassis is grounded. This will explain the behaviour in my circuit with the heating up of the X-Former. I again did continuity checks around the X-Former and could narrow down the problem to the X-former as the adjacent parts are short to ground at the X-Former near sides and are well isolated from ground at their X-Former far sides. The other X-Former in my second  and working build doesnt show that behaviour. I think I need a replacement as I suppose I got a defective X-Former.

Title: Re: EQN build thread
Post by: Bassniac on October 09, 2013, 12:54:38 PM
Wasnt the EA XFormer. Nervertheless, problem solved, Unit is running. Somehow TR3s Collector was shorting to ground via its Heatsink. Some heatshrink tube cured it.

Cheers.
Title: Re: EQN build thread
Post by: thesolidshadow on January 05, 2014, 01:45:55 PM
Hereby my bom ordered at farnell, note the 2 times lr2 reistor because of supplyer ran out of stock. so far i can tell the r720 resitor is missing since i couldnt find it at the website and transistors are missing because i ordered the originals.

hope it is anyone her/his help:

Artikelnummer   Aantal besteld   Productomschrijving   Fabrikantnummer
2329993   10   RESISTOR, METAL , 10R, 0.6W, 1%; Product   LR1F10R
2330004   10   RESISTOR, METAL , 120R, 0.6W, 1%; Produc   LR1F120R
2330197   10   RESISTOR, METAL , 604R, 0.6W, 1%; Produc   LR1F604R
2330201   10   RESISTOR, METAL , 620R, 0.6W, 1%; Produc   LR1F620R
2330226   10   RESISTOR, METAL , 820R, 0.6W, 1%; Produc   LR1F820R
2330037   10   RESISTOR, METAL , 1K2, 0.6W, 1%; Product   LR1F1K2
2330048   10   RESISTOR, METAL , 1K8, 0.6W, 1%; Product   LR1F1K8
2330087   10   RESISTOR, METAL , 2K2, 0.6W, 1%; Product   LR1F2K2
2330092   10   RESISTOR, METAL , 2K7, 0.6W, 1%; Product   LR1F2K7
2330130   10   RESISTOR, METAL , 3K3, 0.6W, 1%; Product   LR1F3K3
2330135   10   RESISTOR, METAL , 3K9, 0.6W, 1%; Product   LR1F3K9
2330191   10   RESISTOR, METAL , 5K1, 0.6W, 1%; Product   LR1F5K1
2330007   10   RESISTOR, METAL , 12K, 0.6W, 1%; Product   LR1F12K
2330031   10   RESISTOR, METAL , 18K, 0.6W, 1%; Product   LR1F18K
2330083   10   RESISTOR, METAL , 27K, 0.6W, 1%; Product   LR1F27K
2330110   10   RESISTOR, METAL , 33K, 0.6W, 1%; Product   LR1F33K
2330125   10   RESISTOR, METAL , 39K, 0.6W, 1%; Product   LR1F39K
2330186   10   RESISTOR, METAL , 56K, 0.6W, 1%; Product   LR1F56K
2330206   10   RESISTOR, METAL , 68K, 0.6W, 1%; Product   LR1F68K
2329987   10   RESISTOR, METAL , 100K, 0.6W, 1%; Produc   LR1F100K
2330002   10   RESISTOR, METAL , 120K, 0.6W, 1%; Produc   LR1F120K
2330029   10   RESISTOR, METAL , 180K, 0.6W, 1%; Produc   LR1F180K
2330232   10   RESISTOR, METAL , 8K2, 0.6W, 1%; Product   LR1F8K2
1800618   4   CAPACITOR, RADIAL, 10V, 680UF; Product R   EEUFR1A681
1831270   8   CAP, ALU ELEC, 470UF, 16V, RAD; Product   16ZLJ470M8X11.5
2330211   10   RESISTOR, METAL , 6K2, 0.6W, 1%; Product   LR1F6K2
2330213   10   RESISTOR, METAL , 6K8, 0.6W, 1%; Product   LR1F6K8
2330223   10   RESISTOR, METAL , 7K5, 0.6W, 1%; Product   LR1F7K5
1834179   10   CAPACITOR, RADIAL, 100V, 0.47UF; Product   MAL203859477E3
1651089   10   DIODE, POWER RECTIFIER,35V,1A,DO-41; Dio   1N4001
1621627   10   DIODE, ZENER, 27V, 1W; Zener Voltage Vz   1N4750A
608609   10   INDUCTOR, 1MH, 5%, 130MA, 1.6MHZ; Produc   B78108S1105J
1141756   5   CAP, CERAMIC, 10PF, 50V, C0G/NP0, RAD; P   K100J15C0GF53L2
1141762   5   CAPACITOR, 47PF, 50V; Product Range:VISH   K470J15C0GF53L2
1141767   5   CAPACITOR, 220PF, 50V; Product Range:VIS   K221J15C0GF53L2
1141768   5   CAPACITOR, 330PF, 50V; Product Range:VIS   K331J15C0GF53L2
1141769   5   CAPACITOR, 470PF, 50V; Product Range:VIS   K471J15C0GF53L2
1141770   5   CAPACITOR, 680PF, 50V; Product Range:VIS   K681J15C0GF53L2
1141771   5   CAP, CERAMIC, 1000PF, 50V, C0G/NP0, RAD;   K102J15C0GF53L2
1005987   5   CAPACITOR, 4.7NF, 63V; Product Range:WIM   FKP2C014701D00JSSD
1166015   10   CAPACITOR, 0.015UF, 630V; Product Range:   BFC237261153
9411887   25   CAP, CERAMIC, 0.1UF, 50V, Y5V, RAD; Prod   MCFYU6104Z6
1753992   10   CAPACITOR TANT, 10UF, 25V, 20%, RADIAL;   489D106X0025D6VE3
1754021   8   CAPACITOR, TANTALUM, 25V, 22UF; Product   790D226X9025B2BE3
2079095   10   CAPACITOR, 68UF, 10V, 6.3X7MM; Product R   EEAGA1A680
1800634   8   CAP, ALU ELECT, 470UF, 16V, CAN; Product   EEUFR1C471
1006037   5   CAPACITOR, 0.47UF, 100V; Product Range:W   MKS2D034701E00KSSD
2330333   10   RESISTOR, METAL , 3K6, 0.75W, 1%; Produc   LR2F3K6
2330254   20   RESISTOR, METAL , 10K, 0.75W, 1%; Produc   LR2F10K
1738612   10   RESISTOR, 2W, 5%, 12R; Product Range:TE   ROX2SJ12R
1738620   10   RESISTOR, 2W, 5%, 47R; Product Range:TE   ROX2SJ47R
2329535   70   RESISTOR, CARBON , 4M7, 0.25W, 5%; Produ   CFR16J4M7
9353631   4   TRIMMER, 25 TURN 5K; Track Resistance:5k   3296Y-1-502LF
8795711   4   POTENTIOMETER, LINEAR, 10K, 1.5W, 10%; T   PRV6SAABJYB25103KA
8795720   2   POTENTIOMETER, 50K; Track Resistance:50k   PRV6SAABJYB25503KA
1653588   2   TRANSISTOR, NPN; Transistor Polarity:NPN   2N4401BU
Title: Re: EQN build thread
Post by: taliska on February 07, 2014, 06:23:39 AM
Peter,

Just to clarify something...is "the James Fix" required for all variants of your pcb? (perhaps might be worth listing the various revs you ship for completeness sake and the corresponding status with regard to the fix too...just in case anyone else is wondering the same thing...)

Unfortunately I didn't notice it in the thread until my board was fully populated, so wasn't able to test continuity or a lack of it first, but judging by the copyright date (2009), I'm going to assume it is required...

Thanks,

Kaz
Title: Re: EQN build thread
Post by: duantro on February 07, 2014, 03:40:43 PM
Taliska,
Read back in the thread to confirm, but if I remember correctly, the James fix was to even out levels while an eq section was disengaged. I built mine within the last few years, and did this fix, which works great. If you are wondering if the fix has been implemented in your circuit boards, just do a continuity check with a meter at the fix points.
Title: Re: EQN build thread
Post by: taliska on February 07, 2014, 06:55:42 PM
Hey Duantro!

Thanks for the info. Yeah, I did do that continuity test, but unfortunately my boards are fully populated, and I wasn't sure that my continuity test could be trusted because of that. When I read through the thread, jrowell asked another member with unpopulated boards to do the continuity test, and perhaps I read too much in to that, but I took it to mean that he needed the additional input because his boards were also populated, and so couldn't be trusted because the additional connections caused a different, longer route between those two points! I'm not a whizz at this stuff, so I do my best the twisted logic in my brain, but it seemed to make sense to me... ;-)

Regardless, I did do the fix anyway, and nothing blew up, so that's good. ;-) I also ran it through fuzz measure after the fix (forgot to do it before though...doh!), and the response was flat with the LF section switched off, so it seems fine.

I got my boards and built them in the last few months, so I just figured a more official word on it might be in order given that jrowell found the fix quite some time ago and enough time has passed for there to be a newer revision, and for that information to be now incorrect...or not...who knows?! ;-)

Kaz
Title: Re: EQN build thread
Post by: jandoste on February 16, 2014, 02:12:27 PM
Hey guys,

I don't know if there is a solution for my problem but I hope that you can give me an idea! I finished up my new 51X rack and it's ready to go! it's awesome! But before I was using API 500 rack so when I built Peter's EQN than I cut the latest pins( Okidoki :) I know that wasn't a good idea) and now I want to use these EQs with the 51X rack... my question is that it'll be possible to find any solution or I must forget to use them in 51X rack?



Thanks for any advices!

Cheers
Title: Re: EQN build thread
Post by: Dr Gris on February 16, 2014, 05:30:13 PM
The 51X rack is designed to give you both +/- 15V and +/- 24V so I don't see a problem
unless you decided to build the PSU to only deliver 24V, but you didn't right?

Best
//M
Title: Re: EQN build thread
Post by: jandoste on February 16, 2014, 05:52:34 PM
Thanks Dr Gris!
Yap, it has +/- 16V and +/-24V. So I can put them in the Rack without the pins 16 and 17! cool!

cheers,


The 51X rack is designed to give you both +/- 15V and +/- 24V so I don't see a problem
unless you decided to build the PSU to only deliver 24V, but you didn't right?

Best
//M
Title: Re: EQN build thread
Post by: jandoste on February 17, 2014, 01:14:27 PM
my bad!
ok, it didn't work ??? I've cut the pin 16 and 17 that i used for the standard 500 f+%%%%k!
so I moved all components no needed for 24V but it won't work without these pins! any other solution?

Thanks

The 51X rack is designed to give you both +/- 15V and +/- 24V so I don't see a problem
unless you decided to build the PSU to only deliver 24V, but you didn't right?

Best
//M
Title: Re: EQN build thread
Post by: Dr Gris on February 17, 2014, 03:37:48 PM
Hmmm....if I understand you correctly, you have cut off the last two pins that sat together
after the "notch" in the connector that goes into the Edac connector in the rack?
Those last two pins are for +24V DC (pin 17) and -24V DC (pin 18).
Looking at your pic, those are the ones you cut ( not pin 16 and 17)

You can still make the module work on +/- 16V in the 51X rack.
Pin 12 is + 16V DC and pin 14 is -16V DC. The last three gold plated pins in your pic is pin 12,13,14.
So you don't have to worry about that you have cut the last two pins :)

But what you have to do is to put back the components you took away to make it work again.
All those parts labeled "not needed for 51X" still has to be there.
And thats because you took the last two pins away.
" not needed for 51X" means you run it from the last pins (24V).

I hope I make sense.

Don't give up, and best of luck, I love my EQN's!!
//Magnus
Title: Re: EQN build thread
Post by: jandoste on February 19, 2014, 02:49:44 PM

Thanks Dr Gris!

OMG! I accidentally removed C12 and now I can't re-solder it :'( there is nothing for soldering the legs of 470uf ... any idea can safe me?

thanks



Hmmm....if I understand you correctly, you have cut off the last two pins that sat together
after the "notch" in the connector that goes into the Edac connector in the rack?
Those last two pins are for +24V DC (pin 17) and -24V DC (pin 18).
Looking at your pic, those are the ones you cut ( not pin 16 and 17)

You can still make the module work on +/- 16V in the 51X rack.
Pin 12 is + 16V DC and pin 14 is -16V DC. The last three gold plated pins in your pic is pin 12,13,14.
So you don't have to worry about that you have cut the last two pins :)

But what you have to do is to put back the components you took away to make it work again.
All those parts labeled "not needed for 51X" still has to be there.
And thats because you took the last two pins away.
" not needed for 51X" means you run it from the last pins (24V).

I hope I make sense.

Don't give up, and best of luck, I love my EQN's!!
//Magnus
Title: Re: EQN build thread
Post by: Dr Gris on February 19, 2014, 03:36:16 PM

Thanks Dr Gris!

OMG! I accidentally removed C12 and now I can't re-solder it :'( there is nothing for soldering the legs of 470uf ... any idea can safe me?

thanks


[/quote]

C12 is a small 1uF film cap in the filter section. Do you mean C1 and C2 (elyt 470uF)
close to the last pins? Can you take another pic of what you mean?

I have those caps (470 uF 25V electrolyt) as leftovers from the kit from Colin as I didn't
put them in, felt bold in going 24V only 8)
Use some solder wick to clean up the holes in the PCB where they once were,
and I can send you mine for free in an envelope if you need them  :)

Regards
Magnus
Title: Re: EQN build thread
Post by: jandoste on February 19, 2014, 05:07:07 PM
Thanks!
I meant there is nothing on the BCP :(



C12 is a small 1uF film cap in the filter section. Do you mean C1 and C2 (elyt 470uF)
close to the last pins? Can you take another pic of what you mean?

I have those caps (470 uF 25V electrolyt) as leftovers from the kit from Colin as I didn't
put them in, felt bold in going 24V only 8)
Use some solder wick to clean up the holes in the PCB where they once were,
and I can send you mine for free in an envelope if you need them  :)

Regards
Magnus
Title: Re: EQN build thread
Post by: Dr Gris on February 20, 2014, 02:44:52 AM
Ok, I'm not that experienced but I have been forced to remove parts I've put in wrong
and it has looked like that afterwards, but it worked to solder again.
Check the board for continuity where you should have it so that the traces are good,
and try to solder again.

I' m sorry I don't have any more suggestions.
Let me know if you need caps.

Best
Magnus
Title: Re: EQN build thread
Post by: jandoste on February 20, 2014, 05:24:04 PM
Thanks Magnus! I think I won't need the cap but it was so kind...

Please someone can tell me which 470uf is the C2 on the schema? because I need to solder contact its leg but where I cannot find :)

Thanks


(http://i1236.photobucket.com/albums/ff442/jandoste/84rough_zps91f89da8.jpg) (http://s1236.photobucket.com/user/jandoste/media/84rough_zps91f89da8.jpg.html)


I' m sorry I don't have any more suggestions.
Let me know if you need caps.

Best
Magnus
Title: Re: EQN build thread
Post by: zayance on February 22, 2014, 08:34:22 AM
Just follow trace on the PCB and you'll find wich one it is and where the trace has to go for proper contact.
Too bad you lifted an electrolyic cap pad, a ceramic wouldn't need to airwire it (going from your pic)but lifting solo pads can happen easily...
Title: Re: EQN build thread
Post by: Bassniac on February 23, 2014, 03:56:13 AM
And Peters PCBs are a little sensitive... speaking of forcing components of their holes and removing the solder. Thats why I bought a reworking station with a vacuum desoldering iron! Happend to me at least three times building 4 EQNs until now. But you learn how to work around and to be more careful soldering and desoldering those PCBs.
A quick and dirty solution is cutting of the components, leaving the components leads in their holes and soldering to the remaining leads. Of course thats a little problematic with radial Elcos.

Cheers.
Title: Re: EQN build thread
Post by: jandoste on February 24, 2014, 12:12:12 PM

Thanks Tony!

I think I found it but I want to be sure ::)
So leg 1(+) goes to pin 8
leg 2 (- ) = L2 ?

Is that right?

Thanks


Just follow trace on the PCB and you'll find wich one it is and where the trace has to go for proper contact.
Too bad you lifted an electrolyic cap pad, a ceramic wouldn't need to airwire it (going from your pic)but lifting solo pads can happen easily...
Title: Re: EQN build thread
Post by: zayance on February 25, 2014, 08:48:05 AM
Jandoste,

Basically you have to rewire as the trace that is connected to the pad you lifted, since you can't make sure that adding solder on a lifted pad will still make a nice connection in the "plated hole" and so the other side pad.
So just take a black marker pen, and put a point on the pad where the wire should go (looking at the trace destination top side of PCB), and hardwire the lifted pad (cap leg) there, done deal.
Can't tell you yes or no for your previous question ;)
Title: Re: EQN build thread
Post by: jandoste on February 26, 2014, 12:14:29 PM
Thanks Tony!

I have soldered the cap and my problem  not solved... I think my problem is on AMP(small PCB) and the AMP side has anything 0V! is it wrong no? and the input tranx is the same; 0V! I also changed Lambda DC's voltages is ok 16V and 9V! after the Lambda DC, I don't get any Voltage! 0V-0V-OV and sadly I can't find the problem  :'(

Thanks
Title: Re: EQN build thread
Post by: jandoste on March 03, 2014, 02:44:40 PM
Hey,

I'm searching the problem but i didn't find it yet! that maybe because of C61/C5/C6 I'm having this problem? I'm measuring them and C5 is 0V but the second build that it works has 24V... please tell me something :'(

Thanks
Title: Re: EQN build thread
Post by: zayance on March 04, 2014, 06:51:55 AM
Can't tell Jandoste, I don't have your modules in front of me, and i'm not in front of mine.

It's hard to help someone with the distance jandoste, and solving problems as you may know can be complicated.
Assembling is always easier of course, but that's not electronics and DIY...
I understand that you fried the module when inserting it in the rack, so if after replacement of the "visually" defect parts nothing changed, than this means that something else is fried (obviously) and the only person that can find that out is you, you have a DMM tester, and I guess a lab PSU maybe? Good that you have a working module, that helps as well.
Going with the schematic first thing would be to see if the Power rails are feeding parts of the circuit etc....
Testing diodes, transistors with your DMM etc... Etc....
Finding the fault can be hard and takes time, but that's part of the deal, I wasted a LOT of time trying to solve issues, sometimes you get things quick and you're happy, and sometimes it's a PITA.
Cheer up, and get things Rollin, after all these kits you should be able to find the fault.
Write down what seems to be looking good and what's not to keep track, because sometimes it's good to take a break and get back to it so.....
Title: Re: EQN build thread
Post by: slegg on April 09, 2014, 11:25:21 AM
Hi,
Is there anybody have EQN kit for sale ?

Thanks
Title: Re: EQN build thread
Post by: fallout on June 21, 2014, 07:06:21 PM
Finally getting around to putting together my EQN's. It only took me about 4 years to get started!

I thought I had a bunch of BC184c's laying around but apparently I haven't a clue where they are. I do have a bunch of MPSA18's and BC550c's laying around. I'm leaning towards using the MSPSA18's (mounted backwards for pin compatibility). Is there any reason to choose one over the other to substitute for the 184c's?

Can't wait to hear these things!
Title: Re: EQN build thread
Post by: Trench Recordings on July 12, 2014, 12:24:20 PM
Any chance on ordering another run of these ?  :)
Title: Re: EQN build thread
Post by: Bassniac on July 12, 2014, 03:30:13 PM
When I asked him the answer was: "... highly doubtful ..."

Cheers.
Title: Re: EQN build thread
Post by: Trench Recordings on July 12, 2014, 05:38:58 PM
Boo ! how many interested people are required for another run ?
Title: Re: EQN build thread
Post by: Bassniac on July 13, 2014, 01:25:14 AM
I would be in for another pair to make it 10.

Cheers.
Title: Re: EQN build thread
Post by: Trench Recordings on July 13, 2014, 03:49:05 PM
I would be in for aleast a pair to start. More than likely I would build 8
Title: Re: EQN build thread
Post by: tzman on July 13, 2014, 05:47:07 PM
I'm in for a pair!
Title: Re: EQN build thread
Post by: Trench Recordings on July 13, 2014, 08:43:53 PM
I emailed Peter. He has a few available now and another batch coming
Title: Re: EQN build thread
Post by: fallout on July 24, 2014, 12:32:07 AM
I just put together my pair of EQN's.. One of them works fine and just needs to be calibrated. However, I'm having a problem with the 2nd one. The low freq switch doesn't have any effect on audio whatsoever. I've double checked the switch and looked for cold solder joints. I tested it with a meter to make sure the switch itself was working and I also swapped amp PCBs. Nothing made a difference! All other switches work fine.. Does anyone have a clue what my issue could be or other ideas on what i can check?

Thanks!

-jay
Title: Re: EQN build thread
Post by: fallout on July 24, 2014, 01:12:17 PM
A good night sleep did the trick. Turned out that it was the jumper jrowell suggested to fix the LF response issue. Unsoldered the jumper and my LF switch worked. Re-soldered the jumper and all is still good! Although it looked fine to the naked eye, it clearly wasn't! ;)

-jay
Title: Re: EQN build thread
Post by: Rob Flinn on August 26, 2014, 04:08:57 PM
On the droop fix, I understand that a wire needs to be connected in the green position.  What is the red wire on the photo ?  Is that something to ignore, or does a trace need cutting ?
Title: Re: EQN build thread
Post by: duantro on August 26, 2014, 04:33:16 PM
On the droop fix, I understand that a wire needs to be connected in the green position.  What is the red wire on the photo ?  Is that something to ignore, or does a trace need cutting ?
The fix is to just jumper the green wire in the JRowell's photo a ways back. This is what I did and mine have been working great for a while.
Title: Re: EQN build thread
Post by: Rob Flinn on August 26, 2014, 04:45:24 PM
Thanks
Title: Re: EQN build thread
Post by: weiss on September 06, 2014, 06:54:18 PM
Got some in stock again?
Title: Re: EQN build thread
Post by: peter purpose on September 26, 2014, 02:54:10 PM
Got some in stock again?

YES
Title: Re: EQN build thread
Post by: Whoops on January 30, 2015, 07:51:48 PM
Hello Peter,
saw in your website that you are out of stock for EQN parcial Kits.

Would you make a new run if I run a Feelers list and have more than 30 orders in the list?

Thanks
Title: Re: EQN build thread
Post by: Trench Recordings on February 02, 2015, 03:27:14 PM
Anyone know the part number for the 1MM pin sockets ? I'm missing 10 and need to order.

I tried some from CAPI but they are too large dia. to fit in the PCB.

Looks like i might a Harwin ? and not mil-max

Edit* - Thanks Peter
Newark/Farnell part numbers...
Pins 1336227
Skts 149-318 
Title: Re: EQN build thread
Post by: Trench Recordings on April 13, 2015, 07:16:11 PM
I have a problem with one of my eqs. It works fine for about 4 or 5 hours then starts acting up. It starts to hum,  sometimes it starts as a slow pulsing hum and then becomes a constant hum.

Powering down for 15 mins seems to clear the problem and it will run clean for another 4/5 hours.

Ideas ? I going to start swapping opamps, DC/DC convertors and see if i can narrow it down

EDIT. I was the DC/DC convertor. Replaced it and all seems good
Title: Re: EQN build thread
Post by: Whoops on April 13, 2015, 08:01:21 PM
Anyone know the part number for the 1MM pin sockets ? I'm missing 10 and need to order.

I tried some from CAPI but they are too large dia. to fit in the PCB.

Looks like i might a Harwin ? and not mil-max

Edit* - Thanks Peter
Newark/Farnell part numbers...
Pins 1336227
Skts 149-318

Can you enlarge a little bit the holes in the PCB to make them fit?

I use a small drill tool to enlarge the holes in PCB's, Works great.

Title: Re: EQN build thread
Post by: late on January 29, 2016, 05:29:30 AM
Hi

Anyone knows where to get good looking knobs? Would like to get bit original look.
Title: Re: EQN build thread
Post by: qmp audio on January 29, 2016, 11:34:32 AM
Anyone knows where to get good looking knobs? Would like to get bit original look.

http://capi-gear.com/catalog/index.php?cPath=202_203
https://www.don-audio.com/Classic-Vintage-small-Trim-Output-Knob-grey-NV-DA84-Neve-Style
https://www.don-audio.com/Control-Knobs
Title: Re: EQN build thread
Post by: KDE on August 31, 2016, 04:42:30 AM
Looking for 1 more kit if anyone has a spare  :'(
Title: Re: EQN build thread
Post by: mysticmerlin on November 01, 2016, 04:28:13 AM
The website for lazpro has gone down and I was just about to finish 4 eqn's . Would anyone have a schematic or something similar (build notes/ calibration guide / Bom) to help me finish?
Thanks
Title: Re: EQN build thread
Post by: qmp audio on November 02, 2016, 02:36:07 PM
The website for lazpro has gone down and I was just about to finish 4 eqn's . Would anyone have a schematic or something similar (build notes/ calibration guide / Bom) to help me finish?
Thanks

https://www.dropbox.com/s/b2gktw9aqvzltjr/lazeqn.zip?dl=0
Title: Re: EQN build thread
Post by: wave on October 15, 2018, 01:33:09 PM
Does anyone know that the voltage should be on the DC convertor pins 2, 3 and 5, 6, 7 when it's working correctly?
Also, should the case of the DC convertor be set in a pin as well? I haven't seen those pins installed in any of the built module pics...


Thanks,
Dave