Hi there,I had a 1st generation T and it was one of the loudest and cleanest tube heads I've ever used.I used it with a 200S cab with 2 JBL E-140's,(8 ohms ea. 4 ohm load) and it killed.Of course you could dial up as much dirt as you wanted if need be.I'd be looking for a pinched wire,or one shorted to gnd.in the signal path,something's dropping your gain and it's not blowing fuses so it can't be anything that draws a lot of current.Good luck,keep us posted,Mel.