Fishman SA220

[dmeek]

This is a long shot but does anyone have a schematic for this? I have one with distortion in Ch 1. It's caused by a DC offset in the op-amps after the EQ and before the phase switch, around the anti-feedback control.
I know this model has problems with bad pots, but they check OK. I'm going bug-eyed trying to trace the SMD circuit.

[DrGonz78]

I have called Fishman before and they sent me a schematic. Of course not this amp but they are very helpful.

Edit: Of course they may only send out schematics of discontinued amps. As far as I can tell the SA220 is not being manufactured anymore so maybe they might finally say yes here is the schematic.

[dmeek]

Turns out it was a pot after all. The base has a metal stand-off with sharp edges It was touching the pcb traces. Only the Anti-Feedback pots have this.

Like this one:



I asked Fishman for a schematic. If I ever get it and they don't object, I'll post it here.

[Jazz P Bass]

Good catch!!

[dmeek]

As promised here is the schematic
Fishman SA220 sch.pdf

[DrGonz78]

I sold one to my uncle earlier this year. So this might come in handy in the future. Thanks for posting it Dmeek.