Mark II C+ Problem

[RnR]

Hello
When I engage the Lead Drive in my amp I get a very loud background buzz, like a bad grounding sound, come one. It is not there in the normal drive. What could it be?

Thanks
Eric

 

[jonathanccwong]

can u provide more details?

ruling out possibilities,

- did this just occur recently?
- what are you settings on the drive pot?
- could be pre-amp tubes going bad. have you tried chaining your tubes? 1 by 1 and see?

 

[RnR]

I just got it a couple weeks ago. Put new power tubes in it and seemed to be doing fine. Really noticed the buzz the last week or so (and I gigged with it before that with no complaints). but man, you got to have the hands of a 5 year old to reach in there to swap preamp tubes. I'll just take it to a tech. I play 'em, but don't fix 'em. Life is to short.

 

[stokes]

9 times out of 10 its a preamp tube.The slightest noise in an early stage becomes a big noise by the time it reaches the out put.I would think its the AX7 that drives the lead channel,but it could be in the earlier stages and isnt heard till you add the extra gain stage in the lead channel.All preamp tubes exhibit some degree of noise,even when you use new tubes,you often have to swap them around till you find the quietest set up.