Sunn SX6350 amp

[jerry]

I sure hope someone out there can help.
I have a Sunn SX6350 amp in the repair shop that keeps frying
no matter what the repair man does. He tells me that he can't do
much more with it without schematics. Does anyone know of a source
for schematics for this amp? Thanks in advance for any help you can give.

[Don T.]

Hello;
 The SX6350 has a very straight forward power section. These units were being produced after the Fender buy-out so you may find help at their web site. I just happen to have a spare power amp section that may help to shed some light on how they're supposed to work. I don't know if I want to sell it cuz it's my backup unit. What city are you in? What kind of problems is it suffering from? Maybe I can help.
Don T.

[rtnet]

I also have a Sunn Sx-6350 that I have been working on for months. Replaced all the outputs,drivers,transistors on board,power caps and a bunch of other stuff. Power supply works fine. Can power up on the old light bulb trick and everything works fine, but as soon as I plug it in the wall it frys the internal fuses. Somthig on the board is allowing to much current to flow but I can't find it. HELP

[rbjohnsn]

I sure hope someone out there can help.
I have a Sunn SX6350 amp in the repair shop that keeps frying
no matter what the repair man does. He tells me that he can't do
much more with it without schematics. Does anyone know of a source
for schematics for this amp? Thanks in advance for any help you can give.

I have this amp also. What I've found after replacing most of the blown components is when powering up the AMP starts to draw excessive amount of current because the center tap of the power transformer, which also is the ground for the speakers, has a parasitic oscillation.

I'll be damned if I can figure out why.