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wrote:
I tried JURB's technique yesterday and 8 resistors burned up. Use
caution

The burnt resistors should point you to the root cause of the failure.
With no load and no outputs there is no reason for anything to smoke
if the circuit works properly. Had the outputs been present they would
probably short first and blow the fuse before anything else could
happen.

Sorry about the eight resistors, but they should point you to a
component which might test good on an ohmmeter but gets leaky or
shorts at actual operating voltage.

Remember DO NOT connect speakers or a dummy load when you do this, it
WILL blow the drivers.

JURB

This one is a subwoofer amp, and probably had a bit of a lightning surge.
Some op-amps were bad, but the amp part seemed OK. Replaced the op-amps, but
the amp was railing out. Looked closer at the amp circuit itself - an MPSA06
transistor was bad. Replaced it, the offset was cut in half, but the bias
was hot. Since disassembly was major just for access, I thought I'd try your
method. Didn't work in this case. Going to order a service manual and get a
better look at the big picture.

Mark Z.