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[email protected] jurb6006@gmail.com is offline
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Default Realistic STA-36

Nine times out of ten "garbled" sound in one channel when the amp doesn't fry or go into protection is because of an open driver transistor. Well maybe 8 out of 10 times.

Without a scope, the only way to test this is either static ally, which means the ohmmeter and the device not powered, or to measure the voltages in the amps while it is running, on a driver the voltage should only be a half volt or so, measuring from base to emitter. It may have forward bias (supposedly) on the base but the emitter is not there, it is more negative or positive than it should be. Except for certain circuits, like class C RF amps n ****, the emitter and base should always be within about a volt. Maybe 2, but no more. The exceptions are high speed switching transistors and that ain't what you got.

You can still get 2SC3117 and 2SC1249 at Digikey cheap and they will handle almost any amp up to about 400 WPC.

Sometimes it is the outputs, read the voltages on the bases and emitters of all of them in the output stages. Even with no signal, on3 of them is going to have more than normal voltage from B to E. Compare it with the other channel.

Anyway, try a few things and get back to us.