MA Audio crossover

I cant seem to figure this out..

Im getting + - 15 volts on all opamps

Im not getting any audio signal back out of this crossover..

Anyone have any ideas?


  • MA Audio.JPG
    MA Audio.JPG
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Guess the guy wants it fixed .

I removed the components where the water damage was and cleaned the board checked all traces and parts everything tested fine ..

I put all the components back in the board after cleaning it ..

Unit powers up still has no output .. The needles do not move and I cannot find audio in any component in this unit ..

Any ideas where to go from here ?
The op-amps have to have some sort of supply voltage. It doesn't have to be ±15v (as you saw in the JBL mono amp) but the op-amps won't operate without supply voltage. The small transformer is likely part of a switching power supply. The most likely faults are the transistors driving the transformer or there is a fault that's not telling the power supply to turn on.