Loud hum from amp in mic

[WhiteStrat]

I've got a 2x12 tube combo. The power section is on the right. And when I mic the right speaker, there's a very loud electrical hum in the mic--but not when I mic the left speaker.

I know--the obvious solution is to mic the left speaker. But I've never heard of this issue before and want to make sure there's nothing wrong with the amp.

I can only assume it has something to do with the power section of the amp. Anyone know about this?

Thanks!

 

[dgatwood]

I've got a 2x12 tube combo. The power section is on the right. And when I mic the right speaker, there's a very loud electrical hum in the mic--but not when I mic the left speaker.

I know--the obvious solution is to mic the left speaker. But I've never heard of this issue before and want to make sure there's nothing wrong with the amp.

I can only assume it has something to do with the power section of the amp. Anyone know about this?

It's induced noise. I couldn't tell you why, though.

Could be a poorly grounded preamp not providing a good enough ground for the mic. Does your preamp have a three prong plug?

Beyond that, the main problem is that the amplifier isn't shielded well enough. Not easy to fix. Best advice is probably to mic the other speaker, honestly....

 

[WhiteStrat]

Yeah, it happens no matter which pre I use (all with 3 prong power cords). So it must be the sheiling on the amp...

Thanks.