Yeah it's a 4x12 with G12T-75's, it's from the early eighties as well. I play metal mostly so I tried to dial in decent sound on lead channel with o/d cranked, tried pull shifts etc. but could not get it, I was rather disappointed but moved on to find a good clean sound on rhythm channel, that didn't take long, sounds awesome, next thing I click back to lead channel(o/d still on 10) and there it is!! I'm too scared to touch anything cause I don't wanna change anything I gotta figure out what all the damn buttons do on this thing!!! Do you think that's pushing it too hard all the time? I'll probably go through tubes pretty fast but I can't really damage anything can I?