i know this isnt a headphone amp but i use it to drive my headphones and speakers, i have a Yamaha A-560 natural sound stereo solid state amplifier that the right channel has gone completely dead on, i know i could fix it, but i need to know where to start, the right is fine, it comes through the headphone jack and speakers just fine, i know ill have to replace something, preferably not the amp, i dont have the money to do that and the amp is actually my dads that i use, i have the service manual and looked through the schematics and i have to say frankly i have never seen the schematic for an amp with balance treble and bass control, i was able to recognize the amp circuit, i know this is a headphone community but could anyone please help me with this?
Fixing a component with one good channel and one bad channel has the benefit of a reference. Using a test tone signal, measure the DC & AC voltages at different points in the circuit. You don't even need a high accuracy meter, you're just looking for differences.
An O-scope makes the AC (signal) testing even easier. With a test tone signal on both channels, starting near the input, look for the area where the bad channel stops looking like the good channel. Then make DC measurements near that bad spot.