SUNN A212 - Not Powering up. Troubleshooting problem...

[jkmierau]

I have a SUNN A212 that won't power up when plugged in. When I reset the breaker on the amp the power light turns on and it starts to make a loud hum and shuts off after a few seconds.
Any advice on what may be the cause to the problem will be greatly appreciated? 

(The last time I used the amp it was working fine. Last night was the first time I have ever had any technical problems with the amp.)

[Ryan Phelps]

If the circuit breaker pops, then the amp is drawing too much current. I'd suspect  the power tubes (6550), the bias circuit and the filter capacitors. You could try swapping the power tubes, but if that doesn't work, take the amp to tech who works on tube gear.

Good Luck!

[loudthud]

Could be a lot of things. One thing to try is to see if it will stay on if the power tubes are removed. A word of caution: Those circuit breakers go bad. It could be bad now and putting more stress on it could make it fail. The best thing to do is take the amp to someone who has the equipment to properly diagnose the problem.

[jkmierau]

alright, thanks.  I'll find someone experienced to take a look at it.