#1
I have a Peavey Ultra 112 that has recently started to act up on me. Its still sounding great, tone wise, but when I hit say a Ab on the top string, I get this kind of buzz in the background. Its really noticeable. It seems to only happen when I really dig into a note, or hit a hard bass note. Its also amplified when I have my TC alter ego x4 running, particularly on a fast Lesley setting. The volume will also drop from time to time. My first thought was a bad power tube, but I switched them out for a spare set I have, and it didn't seem to help at all. I also tried hooking it up to a speaker cab, just to see, and the buzzing didn't seem as bad, but was still there.

This first happened when I was jamming at a friends house the other night. I fooled with it for a bit then, with not luck. We tried jamming and song, and about half way through, the amp started to make a horrendous scream that wouldn't stop until I hit the standby switch. The amp has always been a solid workhorse of mine, with no prior issues. I'm just wondering if anyone here may have experienced something like this before, and maybe to help me out.


Thanks!!

**UPDATE**

I've narrowed it down to a faulty preamp tube in V1. I tired tapping it with a pencil, and could hear a thud come through the amp pretty good. I tried 2 different 12ax7's I have on hand, and all 3 are acting the same. Does this mean I have a bad tube socket?
Guitars:
PRS Custom 24
Gibson Les Paul 60's Tribute
85' MIJ Strat
97' Snakepit Les Paul
LP Traditional 1960 Zebra
MIJ Tele
MIA Strat

Amps:
EVH 5150iii
Peavey Ultra 112
Jet City JCA50H
Peavey VTM 60
74' Vibro Champ
66' Bassman
Pink Paisley
Last edited by red.guitar at Nov 18, 2016,