rhempz01, can you post a pic of the top of the board too? I have fixed a few amps by reading though the posts where you asked for help, they are always indepth. not that this helps you fix the amp, but it could others that learn to do a search first before asking questions.
Amplifier has oscillation at the output transistor and 51.76v of rail is present in the drains as well. And it has audio, looks good on scope but when hooked up, it barely moves the bench sub.
There may be a problem with the remote gain control circuit. R63-20.5KΩ and R60-499Ω are across U4-2068 Pins 7 & 8. They set the gain of U4 when there is no remote gain control plugged in.
Be sure to check the JK1 3.5mm phone jack, if the pins are artificially shorted you will have very little output, as if the control is rotated to a minimum gain setting.
check to be sure R60 and R63 are in value and connected to U4's Pin's 7 & 8.
It's also possible that one of the capacitor supporting the input IC's has bad soldered and a leg is not connected.This can be detected by signal tracing the front end and pushing the caps with your finger and observing from the opposite side to see a loose connection.
Be sure to check the JK1 3.5mm phone jack, if the pins are artificially shorted you will have very little output, as if the control is rotated to a minimum gain setting.
check to be sure R60 and R63 are in value and connected to U4's Pin's 7 & 8.
It's also possible that one of the capacitor supporting the input IC's has bad soldered and a leg is not connected.This can be detected by signal tracing the front end and pushing the caps with your finger and observing from the opposite side to see a loose connection.
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