Soundcraft 600 fixer upper

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Can anyone give me advice on excessive noise on channels. It appears not to matter what module is in the spot. Doesn't make a difference whether it's line or mic or PFL either.

Also, what would cause out LED meters? a few channels are out. I recapped and re-chipped the out meters and they still don't work. Swapped chips from working meters, still nothing.
 
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Okie doke, I'm frustrated.

I moved and pieced out my console to move it. The box the master channel was in accidentally got really wet so I left it dry out for a week. When I plugged it back in, whatever signal I have coming in from the 2 track in comes out of the c/r peakers whether the board is on or not. Hitting switches or moving pots does nothing. What has happened. What do I do? The master channel looks fine but clearly is not.


Ryan
 
Regarding the meters not working - as I recall, only the first 8 will work without patching. I had to patch the 9-16 channels to see them on the LED Meters.

And there's this by ARDE, which I personally can't speak to:

Abbey Road D'Enfer said:
You know that the meters follow the "Tape return" switch on the group module, do you?
 
Regarding the meters not working - as I recall, only the first 8 will work without patching. I had to patch the 9-16 channels to see them on the LED Meters.

And there's this by ARDE, which I personally can't speak to:

Abbey Road D'Enfer said:
You know that the meters follow the "Tape return" switch on the group module, do you?
Thanks for the reply. Yes, I've already taken care of everything in the past. The board was working. Recapped 8 channels, the busses, and the master.

Update: R86, R87, and R89 went up in smoke just now on the master channel. Can't figure out what I've messed up when I disassembled the board. Not sure if I plugged things in the wrong place or if it's from when it got wet but something ain't right.

Bottom left near Con 2 is where the problem is.
 

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I've taken care of all my past questions!

This is a random question I thought maybe y'all can answer.

When I plug my interface monitor outs into the 2-track ins of my soundcraft, How should I adjust the monitor out potentiometera on the interface? Should I have it all the way up? Or can that cause clipping?
 
We can't answer this question, because we just don't know what level your interface is putting out!

Try it!

Well, use your ears... If it clips, turn the knob down.
This actually answered my question. I just think I'm being overly worried about it but it's working well all the way up.

Serious question:
Since I've reassembled, cleaned, and rewired the channels. I'm no longer getting any sound to the main mix OR the direct out from channel 2. I've swapped modules, swapped internal cabling, still nothing. When i plug a mic into channel 2 and turn the gain up and tap it, I'm getting peak indication. Anyone have any idea of where I should be looking for a problem?

Thank you all,
Ryan
 
Serious question:
Since I've reassembled, cleaned, and rewired the channels. I'm no longer getting any sound to the main mix OR the direct out from channel 2. I've swapped modules, swapped internal cabling, still nothing. When i plug a mic into channel 2 and turn the gain up and tap it, I'm getting peak indication. Anyone have any idea of where I should be looking for a problem?
Only ch 2 does it? Even putting any other module in there?
Then I would suspect the insert jacks. Try to insert a jack that shorts Tip and Ring. (IIRC insert send and return are on a single jack)
Or there may be a fault on the rearcon PCB.
 
Only ch 2 does it? Even putting any other module in there?
Then I would suspect the insert jacks. Try to insert a jack that shorts Tip and Ring. (IIRC insert send and return are on a single jack)
Or there may be a fault on the rearcon PCB.
I pulled out that PCB but nothing looked wrong. The insert jack however, I haven't even thought about. Thank you so much for that.

Update: I sprayed contact cleaner in the insert jack, and pushed a trs in and out a few times and now it's perfect. So interesting considering I just meticulously cleaned that whole pcb and all the connections!
 
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I'm having trouble using the unalanced direct outs of my soundcraft board to a balanced gear. Losing lots of level. Could a solution be as simple as wiring a trs to ts jack with the tip and ring both going to the tip of the ts?

Update: thinking now that the balanced cables plugged into the mixer was grounding the signal and using unbalanced cables seems better. Still feel like the signal is low. Should I be removing J11 for -10db instead of +4 to be used with the Focusrite Clarett?
 
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I'm having trouble using the unalanced direct outs of my soundcraft board to a balanced gear. Losing lots of level. Could a solution be as simple as wiring a trs to ts jack with the tip and ring both going to the tip of the ts?
No, that would short the signal. It looks like your cable is incorrectly wired. Tip must go to tip. Actually a standard balanced cable is the correct answer. Unless somebody has modified either the console or the interface.
Update: thinking now that the balanced cables plugged into the mixer was grounding the signal and using unbalanced cables seems better. Still feel like the signal is low. Should I be removing J11 for -10db instead of +4 to be used with the Focusrite Clarett?
It shouldn'tsolve the problem, which is in the wiring.
 
Interesting. Removing the J11 jumper for -10dbv is actually giving me significantly more signal for line level and using unbalanced cables from the channel direct out to my balanced patchbay has essentially fixed my problem though. I'm worried something is askew.
 
I think I figured out why everything seems off. I think VR1-VR4 are calibrated wrong. So I'm getting mismatched signals between main mix and 2 track returns.
 
Well it seems the main cause of noise in my soundcraft is the fader on the master. I've thoroughly cleaned it, recapped, and replaced opamps. Any ideas? I feel like it's probably the infamous ground scheme but I'm not sure I'm interesting in that much work at the moment.
 
Do you mean it makes noise when you move it? Or there's more noise when you crank it up?
When I crank it. I removed every channel and, aux PCB, and meter PCB and noise increases exponentially only when raising the fader.

It's kind of confirmed by the fact every 2 track return is faderless and has no audible noise added. The main mix is the only master channel with the the fader. If I lower the fader half-way and blast the control room potentiometer there is still noise but far less. The fader adds lots of noise .
 
When I crank it. I removed every channel and, aux PCB, and meter PCB and noise increases exponentially only when raising the fader.
It's a problem that was reported to me by customersabout 30 years ago. The reason is that the Input Noise Current is modulated by the fader resistance. I suggested a simple ECO that resulted in swapping the 5532 in the post-fader amp for a TL072, since FET opamps have virtually no noise current. Indeed, the static noise will be slightly higher but there will be no more noise when cranking the fader.
Today, there are FET opamps that are quieter than the TL072, such as the OPA2134.
Even quieter are the OPA 1642, 1652 and 1656, but they are available only in SMD, so require an adapter, and may require increasing rail decoupling for stability.
 
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