Bias drift and burnt insulation

[Smokebreak]

Oh I see. Possibly a bad solder joint saved me.
On a somewhat unrelated note, the amp did fine last night, too, but was too loud (nothing new). Soundguy says on the break "you're too loud, but DON'T turn down, I'm gonna put a blanket in front of your amp". I was only slightly offended, but when I got back, I see that he has constructed a baffle about the height of my cab, about 1 foot in front of it. He said the highs would be forced to "roll" over the top of it, instead of hitting everyone in the face. It actually sounded better on stage, and I actually turned it up and could hit the amp's sweet spot. Everyone was happy. Neat trick.

[JerryFJA]

Jerry, guitar was straight into amp, running 4ohm load. I made the engineer show me the 2x12 8ohm speakers

They weren't wired in series were they?
Jerry

[Smokebreak]

The engineer swore up and down they were in parallel. I would have had to take off the other back panels of the cab to check, which I probably should have done.

[JerryFJA]

A quick check with an ohmmeter is easier than pulling the back off. That sure looks like flyback/high voltage damage to me.
Jerry