This humm is killing me...

[quanahtx]

My best mic is a Blueberry that I usually run thru a Avalon 737.

But it's started picking up a loud LOUD (probably) 60-cycle humm.

When I touch the mic it usually stops right away, usually for a long time, and during that time it's perfect.

But then it starts again, and you have to touch it again, usually several times. Sometimes I find myself begging the mic to stop.

This doesn't seem to be a problem for any of my other mics.

Can someone please tell me where I should start looking for the problem?

Thanks.
Steve in Dallas

[michaelhoddy]

Sounds like you have a grounding issue, whether in the mic, the cable, or the preamp. The easiest way to nail this down is to swap out one component at a time starting with the mic, until the problem goes away,

My gut-level guess is that there's an issue with the mic. Sounds like some kind of voltage potential is building up causing noise, and when you touch it, you send that potential to ground.