Hi all in this awesome forum. I was wondering if anyone has a schematic or service manual for a Memphis Audio prx700.5 5-channel amplifier? I am trying to repair the subwoofer output channel that is outputting 41v DC (!) at the speaker out. I suspect that it could be a shorted subwoofer output transistor that is allowing the full rail voltage (either positive or negative) through. I have no idea what ones are the subwoofer's transistors, though. The four remaining front/rear channels are labelled on the pcb, but not the sub's.
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I would like to know as well. I have one of these with identical symptoms. I believe that M002-M005 are the subwoofer output section. Sub+ is connected to the drains of one pair of B23N20D's and the source of another pair of B23N20D's. I'm having a heck of a time finding the driver transistors for them or the controller IC for them.