PASSIVE RELAY-BASED CONTROLL ROOM KITS BUILD/SUPPORT TREAD

[user 10827]

Hi Guys!

well its dark here now so the lighting is not great but here it is..

Thanks Igor, owe you big time!  ;D

 

[Moby]

Looking great  What's the front finish? Where did you find that cute knob ?  ;D

 

[rob_gould]

Wow!

That looks great.  I'm really impressed.

I presume that's a front panel you've sent to Schaeffer for them to drill and engrave, rather than a piece if aluminium that they have picked and finished?  What's the finish that you've used there?

Also, it looks like there's some kind of smoked glass inset that covers the LED readout for level.  What kind of material is this and how did you fabricate it?

Cheers,

Rob

 

[user 10827]

Hi Guys,

Thanks, yes i had it engraved by Schaffer, and its their own aluminum raw finish, they said they cant guarantee the raw finish but it looks wonderful to me.

As far as the screen insert, i found some tinted perspex and cut it to the shape of the insert i had cut out of the rear of the panel and carefully super glued it in.

I decided on a BIG knob from Banzai, and rather than sit it on top of the panel i cut it out of the panel, and using 10mm spacers the switches are almost flush with the panel... i like that..

but really Igor is the King in all this, i just put it together, that's the easy bit!

pete

 

[Igor]

HOLY SHIT DUDE!!!!

AWESOME LOOK!!!!!

Peter, I am a way happy with this project.

As VERY lazy person, I don't mind (for now at least) to sell things in big qty's.

But I'm happy my designs are working woldwide, prooved by quality and sound
by other people, and making good vibe and music.

 

[user 10827]

Hi Igor,

Thank you.

I never noticed until today that you can trim the MONO and DIM....how you get you head round designing the relay attenuator i have nooo idea...pure genius!

question:

when you set the trim some times it displays SAU? or some thing similar, what does this mean?

On another subject wait until you see my new Sontec front panel...i cant wait to show you!!

pete

 

[Igor]

Hehehe... Cool.

Peter, I never designed relay attenuator
It is old good trick to controll everything, remaining passive circuit.
There was a lot of info about this in Russian magazine "Radio" than later on DIY Audio forum.
I just wrote the "logic" etc which was programmed into PIC by other guy, and adapted this thing for
recording/mix/mastering studio needs as sound tech with some exp in past

Regarding SAV, it is SAVE. Sometimes (it is PIC bug/issue, we didn't found why),
after adjusting the TRIM (level offset) value, it saves current state as initial.
Nevermind.

To see TRIM (level offsets), press and hold TRIM, then corresponding input/output.
To exit TRIM screen, press TRIM again.

Will be happy to see new Sontec pannel.  I suggest it is same nice!!!!

 

[bluebird]

A little off topic but, may I ask what you use the Dolby units for? I heard people use them to get a little high end sizzle on vocals.

 

[Igor]

Are there more people who finnished the kits?

 

[Moby]

Almost... but I'm still waiting for my box  BTW, did you sent me the additional parts I asked from you? I'm not in hurry ,just checking  8)

 

[Igor]

E-mail sent.

 

[rob_gould]

My boards are soldered but I'm still deciding on case options.

I'd really like to get this in a single box in my rack rather than a separate desktop controller, but I can't justify 4RU of space for it in the same way Pete has done.

Igor - can you tell me if there will be any issue flying the buttons and LEDs etc off the control board with ribbon cable?  That way I will be able to squeeze everything into a smaller case...

Rob

 

[Igor]

Hi Rob, I don't think there will be any issues with flying ( ) buttons....
First proto was a way wierd and messy, but worked fine with long wires coming from keyboard to PIC..
Switches are arranged as computer's keyboard matrix, then, no need to run all wires, see schemo.

MEC switches will fit fine on breadboard.

7-segment LED displays however can be a little prob to get off-board.
Too many wires.... Remember, I'm lazy
Best solution will be to take this one:
http://il.farnell.com/opto-images/b14m04n-r/led-display-red/dp/1210820
(they have same 3-wire and power supp. interface)
I used them at first CRM's, till these displays disappeared.

If you need one, can send with hookup schem, just PM me.

Other option is to bredboard controll pcb....Hmm, no, no way, forgive, it is MESS!!!!

 

[rob_gould]

Hehe ok sounds like it's a little tricky but possible.

Thanks for the advice Igor

PS - 33609 should be finished tonight.  Woo!

 

[Igor]

Looking forward!

 

[ruairioflaherty]

Hi Igor,

I just received my Sontec PCBs, lightning fast delivery .  I'm considering this kit for my mastering room but I have a few questions, I've read the threads and taken a look at the schemo but would appreciate your help.

1) How is the mono function handled - is it purely passive?  I've seen people raise concerns about passive mono summing solutions before due to the source outputs having to drive a near short when the attenuation is set to a certain level. Any thoughts?

2) I'm not sure how the talkback combiner is implemented?  Is it possible to use the combiner board and set it up so that the TB signal only just goes straight to a dedicated set of outputs - in my case I could use the sub outs or add another set? 

Cheers,
Ruairi

 

[Igor]

Hi Ruairi, yap, I know about delivery

10% off from CRM kit's price for your patience

1) How is the mono function handled - is it purely passive?  I've seen people raise concerns about passive mono summing solutions before due to the source outputs having to drive a near short when the attenuation is set to a certain level. Any thoughts?

Attenuator's impedance kept very low (3kOhm), it is the point op-amps at soundcard outs are still clean but attenuator's output impedance
worst case is about 800 Ohms, enough to drive long non-audiofool (2-5m cable) without sacrificing transient responce.
Mono function is passive sum through resistors, before attenuator, btw, you can add +6dB offset (user-define-able) for mono.

2) I'm not sure how the talkback combiner is implemented?  Is it possible to use the combiner board and set it up so that the TB signal only just goes straight to a dedicated set of outputs - in my case I could use the sub outs or add another set?

It is simple pair of line-receivers, resistors/opto network which combines source with electeret mic signal and take
level of playback 7 db down when TB pressed, followed by buffer...
In other words, make playback mix for performer on outs 3-4  of workstation; feed it into talkback combiner,
connect talkback combiner's out to phone amp, that's all.
Talkback combiner can be supplied from digital (12v) power supply, I used for this purpose $10 1W DC-DC converter (12->+/-15V).
In this case, TB combiner's ground fully separeted from digital ground.

 

[ruairioflaherty]

Hi Igor,

thanks for the response.  Just kidding about the Sontec delivery, it was no problem.

One last question.  Are the trim settings lost when the unit is plugged out?  If so is there any way around this - a battery backup or a cap perhaps?  i know this is a budget minded controller so I don't expect miracles, the important thing is the audio quality and we know that is good.

Thanks again,
Ruairi

 

[Igor]

Are the trim settings lost when the unit is plugged out?  If so is there any way around this - a battery backup or a cap perhaps?

 

Yes and no. You can store current settings as initial, by pressing TRIM for 10 sec. System will start from stored settings as default.
All offsets, level, system state will be saved as well.
Battery backup... Possible. But, I'd prefer to set up all offsets once and store them,
and each time system switched on, to have it on silent level, WS to mains, etc...

i know this is a budget minded controller so I don't expect miracles, the important thing is the audio quality and we know that is good.

HMMMM.....I'd say it is not budget quality-wise...
I just simplified my commercially awailable CRM and made it as kit with less functions and easyer to build.
Israel is very small country and me tooo lazy to freak with export and mass-pro.
It not worth the nerve cells killed in a battle with burocracy and mass-market..
From other side, if CRM exists as finnished project,
someone has to enjoy and have fun?

 

[Jeremy.Starseed]

Hi.

Did I see the word "kit" somewhere toward the end of this thread?

I am curious...maybe not enough to build this thing from scratch, but a kit....niiiiice

What is included, and what would a rough estimate of cost be ?

Very nice example a few posts above btw. drool-worthy, even B)

Jeremy