CHRISTMASS DIY PROJECT

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Which poject do you want for Christmass?

  • PGA2500 pre (Wiregain-DC)

    Votes: 11 11.2%
  • 2254c-2254 soundpath/33609 compressor's sidechain with HPF

    Votes: 17 17.3%
  • Mastering quality Passive relay based Controll Room Unit

    Votes: 70 71.4%

  • Total voters
    98
  • Poll closed .
Control Room Unit is definatly needed here then i can go with a different control surface and get rid of my HUI! I think the Wiregain Pre is an amazing project and is hardly a second but it seems everyine is needing a monitor controller more at this point!  ;D
 
What do we get for Chanukah? ::)  How about a good de-esser?  Or, better yet, a tube 4-band fully parametric eq with plenty of discrete op amps?  Oh, yeah, add to that high and low pass filters.....
 
Ya vam zhalayu novym godom, y fsyevo horosheva...

(Sorry if that's butchered... I have no idea how else to spell it!)

Wow!!! Absolutely right, just "s novym godom"....
:D ;D 8)

Well, here no Israely who don't know Russian courses and 10-20 phrases...

About 2254c and PGA2500 pre's, don't worry, they will be here, just bit later.

But honestly, never thought crazy project with >50 relays will
take so much votes :))))
...

OK, this is just...."conclusive evidence" all we are at this forum completely crazy:)



 
Why would someone want a control room whrn you can buy for an affordable price the Samson C-control??????




Just kidding,
I vote on the Control Room Also
 
Activated coal....hmmmmm..........
Usefull thing for pre-christmass stomack disorder after hanuka hangover :)
 
Whoops i have 1 C-control Samson and it dont impress me, i feel its dull on the mix.
I know a passif will work better!!
Thanks.
 
3nity said:
Whoops i have 1 C-control Samson and it dont impress me, i feel its dull on the mix.
I know a passif will work better!!
Thanks.

yes, definately!
you have what you pay for with that unit.
it was just a joke

I would love to have a passive unit.
 
OK...

87 votes.

I don't think before 8th dec will be some significant changes.
Yesterday, ordered pcb's for CRM project...just to get 2 first pcb's, test,
then say OK to 100 batch.
Test pcb's will be ready 8th-12th december (hopefully at 8th, my birthday :)....
Here we go:

Front pannel layout:
http://i251.photobucket.com/albums/gg291/diy33609/CRM/plexi_contr.gif

Schematic (still bit messy, but possible to read):
http://i251.photobucket.com/albums/gg291/diy33609/CRM/CRM_SCH.gif
Big one. /right-click, then save target as..../

Audio PCB layout:
http://i251.photobucket.com/albums/gg291/diy33609/CRM/AUDIO.gif

Controll pcb (stuffed from both sides):
Front side:
http://i251.photobucket.com/albums/gg291/diy33609/CRM/CONTR_TOP.gif

Rear/back side:
http://i251.photobucket.com/albums/gg291/diy33609/CRM/CONTR_BTM.gif

I simplified this project as possible without taking down audio quality
to allow the project to allmost everyone who common with soldering
and basic reading of schems....
In other words, people who have biult G1176, Gpultec, GSSL or GreenPre,
can do this.

Votes???Minds???
/anyway, pcb layout is not a subject to change/ :)
 
Hey Igor,

Looking nice! Glad you went with the DSUB 25, far more economical and will allow the unit to fit in a 1U rack, which no doubt will be cheaper to manufacture and take up less space.

Still a bit confused about the 'talkback' options. Trying to make heads and tails of the schematic, seems there is a monitor out which can be used to feed a separate monitor mix? I assume that the MONITOR OUTPUT is feed by whatever IN is selected from the remote or is there a way to feed a DIFFERENT input to the  MONITOR OUTPUT instead of what is going to one of the 3 OUTPUTS?

For example say you are listening to IN 1 through OUT 1 on your monitors, can you also be sending IN 3 to the MONITOR OUT to a headphone amp for the 'talent'?

Also while on Talkback, in a  previous thread you mentioned that an electret mic could be used and the circuit would be onboard? Is this still the case?

For me, and hopefully others this is important, I want to be able to have a small electret mic mounting into the 1U audio PCB rack case and use the controller to be able to turn it on and off, like the Central Station and Dangerous boxes work. Is there a way to control the attenuation of the TB as well, maybe via the remote or a pot mounted to the audio rack?

If it isn't accommodated, maybe your could make a small daughter board that could be mounted to the front panel of the AUDIO rack with a volume pot for attenuation and the electret mic and it can be powered from the rails inside the rack and then feed the output to the TALKBACK INPUT?

Also is the TB switch on the control panel latching or momentary, and or both?

Sorry for all the questions, just trying to get it worked out in my head and for others so we can get the best features out of this unit.

Cheers, and thanks again for the project  ;)

Matt
 
Hi Matt!

Still a bit confused about the 'talkback' options. Trying to make heads and tails of the schematic, seems there is a monitor out which can be used to feed a separate monitor mix? I assume that the MONITOR OUTPUT is feed by whatever IN is selected from the remote or is there a way to feed a DIFFERENT input to the  MONITOR OUTPUT instead of what is going to one of the 3 OUTPUTS?

I decided to move talkback combiner/phone amp outside the box.

First, more than 60% of potential users will not use talkback option.
Second reason, as long as everything is passive, only 12V 2A switching power supply for
relays and logic used.
It is very cheap for these days and possible to buy in most electronics stores.
Then, power supply for audio inside same box will be bit messy.

PCB's for talkback combiner/phone amp will be offered as well for cheap cost.

There's 9 pin SUB-D-9 socket for this purpose.
It feeds balanced signal from input selector (without level controll) and talkback command
to combiner/amp. If there's a need of separate mix in phones, feed signal from
souncard output (say 7-8) to talkback combiner.


Also while on Talkback, in a  previous thread you mentioned that an electret mic could be used and the circuit would be onboard? Is this still the case?

Yes, talkback combiner contains 2 balanced line receivers, electret mic amplifier with "gain" pot,
and kinda "summing circuit" which serves 2 purposes: put down mix level for 7-8 db
and feed talkback signal when TB ON.

Phones signal passes to output at unity gain when talkback is off.
Circuit is simple, 1xquad opamp and 1xsingle opamp, about 25 misc parts total.

I have a small board for phone amplifier, it contains dual opamp and current boosters,
volume pot, 6.3 stereo jack....simple at all, nothing special.
Then, for phones, just take one combiner board and some
phone amp's boards, put this into 1RU...done.
Or use talkback combiner with external phone amp.

For me, and hopefully others this is important, I want to be able to have a small electret mic mounting into the 1U audio PCB rack case and use the controller to be able to turn it on and off, like the Central Station and Dangerous boxes work. Is there a way to control the attenuation of the TB as well, maybe via the remote or a pot mounted to the audio rack?

Answered :)

If it isn't accommodated, maybe your could make a small daughter board that could be mounted to the front panel of the AUDIO rack with a volume pot for attenuation and the electret mic and it can be powered from the rails inside the rack and then feed the output to the TALKBACK INPUT?

Answered :)

Also is the TB switch on the control panel latching or momentary, and or both?

Talkback is momentary, but when pressed for more than 5 sec, it latches on. Press it again to off.

Talkback have an offset-user adjustable value, 0-40 db, which puts down monitor level
when talkback in.

BTW, offsets is very usefull thing.

To define offset level:
Press TRIM+IN1 for example
Screen shows offset value
Set offset with rotary (say, 3 db)
Press TRIM again, screen shows level.

To save all offsets and current system's state as INITIAL (when power up),
press TRIM for 15 sec, it shows SAVe, done.

For example:
LEVEL -40
IN1 and MON1 selected
Offsets:
-3dB for CD, IN1
0db for Workstation, IN2,
+1 db for NS-10, MON1
0db for Genelec, MON2
-12 db for talkback,
+6 db for MONO
-30db for DIM

Sorry for all the questions, just trying to get it worked out in my head and for others so we can get the best features out of this unit.

Matt, all these are good questions.

Feel free to ask.
 
Hey Igor,

Thanks for all the great answers! I can't believe I'm the only one asking them as this is GREAT project, but it isn't going to be cheap so we should flesh out now what CAN and CANNOT be done with this unit. As always, you are have thought WELL ahead of the rest of us  ;D

I was wondering what the 9 pin D-SUB was for, now it is all clear.

I understand the need for keeping the PSU AWAY from the audio path, esp. since it is passive and will eliminate stray EMF from a transformer from adding any noise, keeping it clean and making it 'easier' to build.

In my case I use a personalized headphone monitoring system for the talent so won't need the amps, just a balanced/unbalanced signal to feed the headphone distribution amp so that talkback can be routed on a pair of of sends from the soundcard as you shared.

Does the combiner/phone amp takes it's power through the 9 pin D-SUB or will an ADDITIONAL power source be required for combiner/phone amp? Wouldn't it make sense for the control unit to have the combiner/phone amp built into it as well, so one cable for the HDF15 connector to the control box and one 9 PIN D-SUB to the control box as well? It would do away with the need for an additional case and an electret mic would take up little space on the control box, assume there is enough space?

If I read your schematic correctly 12VDC is sent out via the DSUB 9 so it could be utilized to power the combiner/phone amp if fitted to the control box?

Maybe I'm over thinking things, maybe I'm the only one who need talkback and as you say 60% of guys don't, anyone interested in this project care to chime in about this feature?

Maybe we could poll it and Purusha could offer 2 different control boxes, one that will accommodate the combiner/phone amp's have 2 headphone outs and and electret mic built in? it does away with the need for an additional 1U rack esp. if it only needs to contain a pair of headphone amps and the combiner circuit?

RE the flexibility of the TRIM controls and saving settings, this unit is CRAZY, a bit like you ;-) Being able yo save customizable setting like this is great and I think it practice will be even more exciting than reading about it here  ;D

Thanks again for all your hard work!

Cheers

Matt
 

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