PASSIVE RELAY-BASED CONTROLL ROOM KITS BUILD/SUPPORT TREAD

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Did anyone ever get a mute switch figured out on these?  I'm interested in building one for my mastering room, without talkback, and a mute switch would be the only thing missing.

On your original Igor, you've got 2 speakers and 1 sub.  I assume this could just be 3 speakers?  Or is #3 a latched switch that is meant to connect with another speaker, like the Presonus Central station?

Thanks!
Sig
 
Out 3 is latching (but the in/outputs of the unit can easily be swapped to a 3 in and 4 out configuration). The amount of attenuation of the dim switch is also variable, this could be your missing mute switch?

Hth, christoph
 
crisotop said:
The amount of attenuation of the dim switch is also variable, this could be your missing mute switch?

Not variable enough to act as a mute. If anyone figured this out it would be a breakthrough. I have to turn mine down all the way whenever I want to mute it (which is pretty often). Its definitely the biggest drawback on an otherwise great piece of gear.

Best, Ben
 
Gotta be some easy way to build a mute switch into these, no?

Sounds like just the unit I need for my mastering room.  I've contacted Igor about the kit price mentioned on the first post of this thread, but his other thread in the White Market doesn't mention the kit at all.  Anyone know if the kits are long gone?
 
Siegfried Meier said:
Gotta be some easy way to build a mute switch into these, no?

Sounds like just the unit I need for my mastering room.  I've contacted Igor about the kit price mentioned on the first post of this thread, but his other thread in the White Market doesn't mention the kit at all.  Anyone know if the kits are long gone?

I think they are I'm afraid.  I recall Igor mentioning he was having a clearout of some of his projects and would not be restocking them after they'd all gone.

I've built the mastering controller though and there are no particularly obscure parts, just a lot of relays!  However, a BOM never did materialise despite me requesting it at the time, but in the end I didn't need it.  If you can get that you should have no probs whatsoever getting the parts you need.
 
Hello all,

I finally got a chance to plug in my CRM and was absolutely delighted with it the evening I fired it up, it worked beautifully! I have it paired with an Apogee Rosetta 800 converter on my project setup with a Pro Tools Digi 002, you don't need me to tell you how much better it was listening through the CRM after being plugged straight into the stock digidesign converters and their built in monitoring section. I'm really impressed and grateful that Igor hooked this project up for us.

The next day though things went a bit weird, I got the U20 message on power up, then lost the ability to control volume on Spkr 1, and while Spkr 2 worked the display didn't change along with the level. Spkr1 was stuck at one fixed volume; no lovely click click from the relays anymore, though Spkr2 still changed volume while the display remained fixed at -14.

On top of this, when switching between speakers there would be a terrifying loud click sent to Spkr 1 - just one big nasty transient.

I read through this thread in the evening and found Tim Campell's post about tracing a fault back to a sticky button on In3. Today I bashed away on that same button and found that switching inputs back and forth a bit does allow me to now control the volume on Spkr 1, but the big click is still there on switching, and the unit always boots up displaying the U20 message and "defaults" to the faulty scenario described above (no relay/volume control on Spkr1, display fixed at -14 even when Spkr 2 is changing volume, and big click when switching speakers)

Does anyone have any idea why this might be happening? The unit has not been moved at all since the first night when it worked absolutely perfectly, the only thing that has happened since then is that it's been switched off then on again. I'm wondering if there might have been some kind of crazy rogue power surge that messed with the chip, or maybe if the fact that I hadn't pressed In3 that first night might have not revealed a problem on that part of the circuit.

Any thoughts most gratefully appreciated - I can't stand the thought of switching back to the monitor outputs of my Digi 002 but am worried about doing damage to my monitors from the transient on switching.

Cheers,

D :)
 
Thanx for note about sound quality.
To be honest, it is one of world cleanest possible level controllers.

For further use: TRIM+another button means you press TRIM, hold it,
than press another button like SPK1 for example, then leave fingers from both buttons.
Exactly same way as CTL+C.


Mute function.
There is a DIM button
After startup message, U20, press TRIM+DIM, exactly like you press CTL+C.
You will see -20. Adjust it to -40, it is "mute'ish" enough.
Then, PRESS TRIM AGAIN!!!!!!
You will get to previous screen, maybe, setup will be saved.
To be at save side: check TRIM is not lit up;
press: IN1, MON1, check level is about -40, check no another buttons on,
than, press TRIM for 10 sec, you see SAV.


If somehow the setup was F@cked up.
It happened me when there were shorted buttons at startup.
Can be caused by bad +5V.
It is not the bug of software and can't be corrected.
The microcontroller goes in wrong state.
Guys, PLEASE!!!!! check everything before power up.
I can't take a care on solder blobs, improper soldering and other f@cks.


To solve frozen screen etc.
CHECK EVERYTHING!!!!!!
Than,
DO EXACTLY LIKE HERE:


Turn unit off.
Wait till power supply goes down completely, say, 1 min.

Press and hold TRIM, power up the unit. Wait.
It will show StU (setup). Stop pressing the TRIM.
Nothing to be settled at this stage, setup proc cleans the EEPROM.
After 7 sec seeing the STU, press TRIM again, you get SAV (save) on screen.
You cleaned the EEPROM and trim offsets were set to default.
Check IN1, SPK1 are on, level -40. TRIM is OFF!!!!

Than, to be at safe side, pass on every possible trims.
I.e. press TRIM+IN1 see 0 than press TRIM again;
SAME!!!!
TRIM+IN2, see 0, press TRIM;
TRIM+IN3; see 0, press TRIM;
TRIM+IN4; see 0, press TRIM;
TRIM+SPK1, see 0, press TRIM;  
TRIM+SPK2, see 0, press TRIM;
TRIM+SUB, see 0, press TRIM;
set up ALL!!! 0 offsets for inputs and outputs.

Than, check TRIM is not ON.
If TRIM is ON, turn it off.

Than, press IN1 (pressing IN1 starts the program), SPK1, adjust level for -40,
hold TRIM again 10 sec. It will save initial setup.

Power down the unit, than, power on.

It should show -40, IN1, SPK1.

Then,
press TRIM+MONO, check or set (-6), press TRIM, MONO to get to prev.screen;
press TRIM+DIM, check or se  (-10...-40), press TRIM, DIM;
press TRIM+TBK, check or set (-6...-20), press TRIM, TBK;

check buttons TRIM, DIM, MONO, TB are OFF!!!!!;
check IN1, SPK1, ON; display is -40; press TRIM 10 sec, this will save correct setup.

Power down, wait, power up, check IN1, SPK1, -40, press IN1 to start the prog,
check everything works fine.....DONE!

Again, before setup: check there are no shorts or wrong solder joints etc.
Worst case, if you somehow lucky f@cked up the micro-controller,
I can send new one at self cost.
 
Awesome thanks Igor! I'm back at home now but will check this out in the studio tomorrow. And yes - sound quality simply stunning - I'm so happy with the performance of the CRM.

 
Hey Igor.
Nice kit. A mate of mine has ordered one, and I've whipped up a controller for it. I realise the kit comes with the controller pcb, but we have a spare lawo board waiting for a purpose. Means we dont need to get a front panel made for it.

Anyway, I'm in the middle of programming the PIC, and I was just wanting to know the pinout/wiring of the A6833. I.e. what port to what relay.
Either that or a schemo with the control side of the relays to the A6833 shown.

Cheers,
Andrew
 
Hey Bonnie!!

Welcome to the forum!!

Just to clarify, I am the guy who ordered the CRM that Bonnie wants to modify. As it goes, we don't feel that the controller offers all the options we want (no mute being the biggie, but we also want fixed 'preset' volume levels) which is why Bonnie has spent time and effort writing code (some straight up in hex - respect!) for this!

Im looking forward to building 'the other half' of this...

Mo
 
Hey guys, sorry, all mods - at your rescue only.
In case of whatever, contact me by mail or skype, will help if this not taking too many time.
A6833 will be discontinued very soon, not rec'd for new designs.
I did not wrote the code for CRM, mine are:
idea, algorytm, schematic, PCB layout, front design and tech implementation....
PIC programming for this project was done by my friend at 2005.
He left Israel few years ago, and now I working with another programmer.
Thus: no code, no code updates, no changes.

"fixed 'preset' volume levels" are already here, btw, you can easy store them.
-50 db is "mute" enough.

I still have about 8 CRM PCB sets. The support will be for about a year,
anyway, I want to clean the stock and forget this project. Same as PGA2500 pre',
it is not DIY-friendly.

From the other side, I did design for very similar CRM project, active, without digital control
and quite more DIY-able.

New CRM has: 4 inputs (1 of 4), 3 outputs (can be 1 of 3 or paralelled),
mono, mute (dim), AND great A/B option.
It can be used as simple mastering console with 2 inserts or CRM
with A/B test compatibility.
Talkback can be easy added here.
It is not hi-end as relay-based, passive CRM, but quite more DIY-friendly,
and, trust me, better than monitor section of $$L G4000 (G6000).

 
Hi Igor,
    Are these CRM sets that you have left complete kits with all parts needed (excluding case) to build the unit?  I am about to place and order with purusha for a bunch of cases and if you have kits left I will order a case for the CRM as well, thanks in advance.

Chris
 
Caprock -- I asked Igor via email last week or so about a full kit, and he responded that the parts are instock.  The price, though, was pretty high, and I think you'd be able to source them locally for less maybe.  Igor also included a BOM in that response, and I started looking things up, but decided to not build this project now, so I didn't get very far.
 
Igor,

Need to use some more wires on the VGA connection.

In fact these:

-12V
L-CH +/-/Gnd
R-CH +/-/Gnd

(I like to integrate some meters in my remote)

So the question: do you see any problems for the digital connection between the pic and the relay driver on the audio board?

The audio connections will be buffered, so there should be no backscatter into the main audio (which i will take from the MTR points)

---

and another one: I did read trough the whole thread, but i missed the function of the dip switch except "DIP3 switch SW2 used to equalize speaker's impedance. "

SW1 and SW3 are for ?

EDIT: Stupid me. Impedance for Spk 1 - 3, correct? ;)
 
Last Q for today ;)
If you want to use brightness controll option, install R20,21 and use photoresistor-
allmost everything will work here... Roff >100k, Ron 0.3...2k.

Cannot find LDRs with Ron 0.2..2k. Easy to find are 4k to 12k Ron.

On the datasheet for the MM5450 (on your shematics its 5540) there is a max. of 4.3V @ 750uA stated. So just decreasing R21 (1k8) using these values? Should i modify R20 (22k) as well?

 
@dtonthept: whazzup? News? :)

@CapRock:
    Are these CRM sets that you have left complete kits with all parts needed
    (excluding case) to build the unit?  I am about to place and order with purusha
    for a bunch of cases and if you have kits left I will order a case for the CRM as well,
    thanks in advance.
   
Yes, we have parts for kits, enough for 5 CRM's.
The price is same as last 2 years, full kit EUR368, if you bought PCB's, math is EUR368-USD110.
Kit include everything except: box, power supply, IEC socket, VGA cable.
   
(I like to integrate some meters in my remote)

Good idea. I like it.

IMHO separate cables for audio is best solution.

I'd connect THAT1246 at audio side to
meter feeds and used it's out as unbalanced feed to meter integrated in control.

It is possible to feed meter driver from small 12->+/-15V dc/dc converter.

Easy to find are 4k to 12k Ron.
OK....It is fun to have a brightness of 7-seg. display adjusted all time to lite at the studio.
But.....not MUST :)
decreasing R21 (1k8)
Leave it as is, the maximum brightness can be easy to see at daylight
which almost never found in normal studio..... IMHO the combination of 4k ROn photo-R and
values shown at schematic will work.

I use r20=8k2, r21=not installed, Photo-R=not installed, and it is enough.
 
Igor said:
Good idea. I like it.

IMHO separate cables for audio is best solution.

I'd connect THAT1246 at audio side to
meter feeds and used it's out as unbalanced feed to meter integrated in control.

It is possible to feed meter driver from small 12->+/-15V dc/dc converter.

THAT1246 ... isnt that overkill? We dont need sonic capabilities for a meter feed, or do we for some other reasons?

I was thinking just to add non-inverting buffers to avoid getting noise or other stuff from the control box/cable back into the audio part. Like to keep the one wire solution. Do i miss something?

In fact two build JLM 40vuppm led meters sitting on my desk waiting to jump into my control box  ;D

OK....It is fun to have a brightness of 7-seg. display adjusted all time to lite at the studio.
But.....not MUST :)

Thanks. Well, like you said .. its not a must ... but fun.  8)
 
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