Schematic Needed for a Gretsch Accordion Amp.

[prs_matt]

I have a Gretsch Accordian amp in for repair and I cannot find a schematic for it anywhere. It is similar to a Valco 6650TR but has a 6DR7 in place of one of the 12AX7s. Tube lineup 5 12AX7, 1 6DR7, 2 6L6, 1 5U4. Tone stack seems to be a Bax.

It sounds good most of the time but has a significant volume drop that comes on suddenly accompanied by a fizzy distortion especially when I play bass notes on the guitar. My thoughts were either leaky power supply caps, failing plate resistors, or a bad bass cap in the tone stack.

Any help would be appreciated.

-Matt

[prs_matt]

I am still looking for this schematic. Model number is confirmed as a Gretsch (Valco-made) Model 6164. If anyone has a schematic for it, please let me know, I am willing to pay for a copy.