Hi, I have a Marshall Origin 50C, and it started to degrade in sound. I checked the circuit and descovered that the, C31, eletrolitic capacitor is leaking, and the acid have deleted the info of the capacitor values.

Can anyone please help me with this information?

Thank you.

1. Tilt knob - does it affect Treble (above  4khz frequencies) or Upper Mid (1khz - 3 khz) frequencies?

2. Does Master volume knob on this amp, if set to 10,  actually produce power amp (EL34s) distortion or is it just a control for the overall volume output (loudness) with no influence whatsoever on power amp distortion ???