03-21-2015, 10:51 PM
Ron, are you sure the distortion is in the power amp stage? Since you now have distortion on both channels, perhaps it originates in the preamp or control amp circuitry?
You might check the DC supply voltage to the preamp stages. If the regulated DC supply is dropping it would cause distortion on both channels. Check for constant 22 VDC on the emitter of Q20, the regulator transistor.
You might check the DC supply voltage to the preamp stages. If the regulated DC supply is dropping it would cause distortion on both channels. Check for constant 22 VDC on the emitter of Q20, the regulator transistor.
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