Peavey amp

[.Chalder]

Ok my peavey amp studio pro 112 just all of a sudden started making a real strong buzzing noise today, its instant as soon as i switch it on, and when i hook my guitar up no noise is made by it.. even when settings are changed.

Please help.

[52 Bill]

Turn down the reverb control and try thumping the top of the amp with your fist. Can you get it to stop/change the buzzing? It may be a broken solder joint on one of the power supply filter caps.

[Enzo]

Does the speaker cone move one direction and then stay there? In other words, is ther DC on the output?

When an output transistor shorts out, this puts DC on the output and the result is a LOUD hum. No signal will pass. DOn't leave it on, this is not good for the speaker.

If you have a failed main filter cap or the solder to one cracks, the result is also a loud hum, but not quite so loud as the other failure mode. ALso, the signal sill come through with the bad cap.