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Old 5th November 2011, 09:23 AM   #1431
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It's shiny again! Thank you all for help!
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Old 5th November 2011, 01:39 PM   #1432
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It's shiny again! Thank you all for help!
Not at all...
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Old 8th November 2011, 08:56 AM   #1433
cersepn is offline cersepn  United States
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Thanks for the advice. After i swapped channels.. that was when i realized something was amiss. After swapping in different preamps and sources, i found out it was actually the amp with a dead channel

It must have gone dead when i unplugged the right DCB1 channel live and heard the boom sound.. Was fine before that. Not too sure what to do now
Okay.. got my repaired amp back and still no sound on one channel with the dcb1. There's sound on both channels when i plug the source in directly into the amp this time, so.. the amp's definitely working. This time i took the volume pot out, soldered the input RCAs directly to the board. Still no sound!

So this means there's something spoilt on the board. The resistors and relays have all been swapped out already.. so that only leaves the quad matched 2sks... Anything i might have missed out?

Last edited by cersepn; 8th November 2011 at 08:59 AM.
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Old 11th November 2011, 10:09 AM   #1434
cersepn is offline cersepn  United States
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Dang, turned out the input wiring was wrong on one channel, sorted that out and now sound is back on both channels, but there's still another problem. One channel sounds weird, almost like it's out of phase (but speakers are not, already checked), vocals very recessed and overall, very strange tonal balance and softer than the other channel.

The other working channel sounds absolutely beautiful, just what you'd expect. Both channels have zero hiss/hum/noise at all times.. so not too sure what to do now. Any ideas?
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Old 11th November 2011, 11:00 AM   #1435
Salas is offline Salas  Greece
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Swap the channels at DCB1's input, then output, so to know if the problem resides in this stage or before/after.
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Old 11th November 2011, 12:38 PM   #1436
cersepn is offline cersepn  United States
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Thank you, Salas. You're a great help as always

I swapped the output and the weird channel switched over.

I tried something else, this time with my active speakers. No input at dcb1 (RCA not soldered to pcb), only output is connected to active monitors. One speaker has a funny squeal, the other is dead silent.

But when i swapped DCB1's output, BOTH speakers have the squeal this time. The strangest thing is with the passive setup there is no funny noise whatsoever. All transformer wires, signal+ground are twisted tightly. I'm really at my wit's end...
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Old 11th November 2011, 01:52 PM   #1437
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@cersepn, what has not been replaced on the front end?
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Old 11th November 2011, 01:59 PM   #1438
Salas is offline Salas  Greece
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Try 1K output series resistors instead of 220 Ohm. Maybe you got instability in the interface to the actives.
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Old 11th November 2011, 01:59 PM   #1439
cersepn is offline cersepn  United States
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Tea-Bag: Front end meaning?
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Old 11th November 2011, 02:06 PM   #1440
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Tea-Bag: Front end meaning?
Not the power supply section
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