Solid State Guitar Amp Forum | DIY Guitar Amplifiers

hey all, I'm a newcomer with some much needed advice.

I've had this Crate GX 212 since i was a teen and don't want to part with it due to these issues so i'd rather repair them if i can myself!

major issue is a loud humming when in overdrive, either channel.
also a loud pop when i turn it off.

now ive read a lot of threads dealing with pop and nobody seems to know what the hell they're talking about, if you do please help!

thanks,
Adam

*Maybe* you don't have a problem.
1) Does the hum (when overdriven) stop or substantially diminish when you close the volume of your guitar to 0?
Does it change when you move around?
Because on high gain settings (overdrive/distortion) every little noise gets amplified a lot.
Build a shorted plug, and plug it into the input jack, ¿what happens to that hum?
2) Turn-off pop is quite normal . It can be reduced, though.
Good luck.

And alternatively, while most solid state amps pop at turnoff, if you have for example an op amp in those preamp channels that has gone to DC on an output pin, that could be the cause of a lot of hum and would make turn off pop much louder than otherwise.