Loud hum from Marshall AVT?

Stompbox

Only happens when I trigger the overdrive channel, but there's a very prominent buzzing sound that won't go away. What could produce such a noise?

balducci

you've probably never changed the tube in the amp, chances are it's that.

8k2q1gfcz9s5d4

balducci wrote: »

you've probably never changed the tube in the amp, chances are it's that.

I doub it, those pre amp tubes last a very long time. OP did it always hum or is it new thing? I used to own an MG and it always hummed on the OD channel

Stompbox

I can't recall if it always hummed. It's only when I turn it up pretty loud actually, maybe the sound is coming from the amp itself as opposed to out of the speaker?

Stompbox

I can't recall if it always hummed. It's only when I turn it up pretty loud actually, maybe the sound is coming from the amp itself as opposed to out of the speaker?

Stompbox

I posted a vid of the hum, if you could spare 30 seconds I'd really appreciate it!

Ravelleman

Video unavailable.

I used to get a hum from my ENGL a few years ago. At first I thought it was the tubes but in the end it turned out to be interference caused by the bathroom light, on the other side of my house.

Any CRT monitors or dimmer switches near the amp?

Stompbox

Video is available again. I think it takes a while for the video to become live on Youtube!

artvandulet

does it make the same noise with nothing plugged into the input?

happyman81

Possibly a capacitor issue.

Squidgy Black

That could be anything. You're using a telecaster, presumably with single coil pickups, so it could simply be the hum from the pickups. Try it with a guitar with humbuckers, and possibly a different lead to eliminate this possibility.

It could also be a mains hum, or interference from a lightbulb. Try it somewhere else to see if that's the case.

Then again it could just be the amp itself. There's bound to be hum on an OD channel anyways, but this would be the least possible one in my opinion.

reniwren

its interference from something like a light or a laptop going to your single coils

Stompbox

artvandulet wrote: »

does it make the same noise with nothing plugged into the input?

Yep, it still makes the sound. When I turn the Volume or Gain fully up on the Overdrive channel, the buzz develops into a persistent ringing noise.

happyman81

really sounds like a dodgy cap. is it still unnder warranty? or, coukd you bring it back to the shop?

Stompbox

It's not, it's a few years old. What's a dodgy cap? Capacitator?

happyman81

Stompbox wrote: »

It's not, it's a few years old. What's a dodgy cap? Capacitator?

Yeah, my AC30 sounded just like that and it turned out to be a broken capacitor. Send it to a tech, I'd say.