I just bought a used Carvin 4x12 (it was 350usd from GC!) I know that for tube amps the omage needs to match from the cab/speakers to the amp. So heres the details: the randall combo 1x12 is ''mosfet'' and of coarse it has a fuse, and the ''max output'' goes: 75w @ 8 ohms / 100w @ 4 ohms, ''parallel link/8ohms min. load''. Then I plugged it in to the carvin's ''left 8ohm mono'' jack, played thru it for prolly an hour worked great then i still had every thing on while switching guitars (which took a while becuase i was tanggled up in cords or something) and then a few LOUD pops - it's done this before but when turning off and not that loud. before i could plug in again it just took a crap.

sorry for the giant paragraph, im doing this on my phone so it looks a little different typing this im getting rid of a virus on my computer at the moment.
Yeah. But the same can be said for DAR amps and other amps which use "weird" tubes...dammit I want a pair of KT120s..I might blow up my amp and burn my house down, but at least I'll go out in a blaze of glory