On my Fender 65 Super Reverb Reissue, I've been using a Weber attenuator and Ibanez Tube Screamer, so I've been pushing the tubes a little bit, but not a lot.

Last night and today I had what sounded like a tube going bad: lots of noise in the tone, the volume cutting out and then the volume being low. By the time I'd start taking things out of the loop to figure out what's going wrong, everything would get back to normal.

I'm assuming it's a tube going bad. Is there any way to tell other than just waiting? Would it likely be a power tube, or another (I just bought a new pre-amp tube).
If the volume is going up and down its most likely power tubes.
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Quote by lucky1978
If the volume is going up and down its most likely power tubes.

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Waiting until they actually blow is foolish. Sometimes when they blow they take out the screen resistor too - or worse.
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