Hey guys. I have an old ampeg tube head and last time i went to go use it i heard a sizzling sound coming from the back of the amp and then it started to smell like something was burning but no sound was coming through. So i turned it off and back on and now i get the same sizzling and burning smell but it also gives off a very lound feedback hum through the cab even when the volume is off.

I'm wondering if i just need new tubes or if the whole amp is shot.
It could be may things really.

My guess would be its either a tube or a capacitor.

Id start looking at the tubes in it.

Are any of the tubes cracked, broken, or not even lighting up?
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Egnater 4x12 cab w/ Vintage 30s
Best thing to do is to take it to your local tech and let him\her look over it.
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yeah, defiantly take it to a tech. Sounds to me like a transistor or capacitor. I've never had bad tubes act like that.