Look like the left output was damaged by +48V being applied to it by mistake. Any Replacement part that can be changed out for the left output channel or perhaps both main outs?
Outputs should be able to handle phantom power wrongly applied as that’s the purpose of the output capacitor to block that. If the phantom blocking capacitors are time expired or faulty then its almost certainly an op amp in that channel that blew.
Replacement parts for mixers are almost non existent. What I would do is put a signal on that channel and follow the op amps signal line backwards from the output and see where the signal isn’t. Working op amps will have a signal at both inputs and outputs. The damaged op amp will be missing the output. Along with the op amp, change the output capacitors on both channels as they failed to protect the circuit, and increase their voltage ratings to non-polarized 63V or 100V.
Its possible the phantom power became higher than 48 volts in complex setups or shorted, and this has been one area where manufacturers have been using the bare minimum rated parts
Thank you Sir, The blown caps makes sense. Its an older unit. I notices that with an XLR connected to the bad out put it’s messes up the signal on the other channel. When i un-plug from the bad channel the good channel signal clears up. I now need to track down schematic’s to ID the Op Amps, Would a Stereo outputs L & R share the same chip? on a multi-op amp chip one element could be blown and not the others right?
Just on the off chance, some jacks connect that channel to ground when unplugged. Just give that a test too.
