Yesterday I plugged in an old AC30 and started to play. Not too loud--if that is possible with an AC30. Everything sounded great for a few minutes...
...then, the amp took on a life of it's own and started making this noise that started out sounding a bit like feedback, but much worse.
The best way to describe the noise would be the sound of pigs in a slaughterhouse in those disturbing YouTube videos--squealing...screaming...needless to say, it was extremely unpleasant and worrisome.
Even after I removed my guitar cable from the amp input. The noise remained (so it's something happening inside the amp). It disappeared slowly when I turned off the amp.
I let the amp cool down for a while, then I plugged in and turned on the amp again. After a few minutes later and the same thing happened.
The amp is a 64 non Top Boost model. I had the two non-vibrato channels jumpered. I was getting a bit of a warm amp smell, but no smoke
Can anyone help me out on this?