I just picked one up and it sounds great. I do like to tinker a little with yubes and was wondering if anyone had some opinions on tube swapping in that amp. Right now it has the standard set up. JJ 12axy, GE 5751 PI, JJ El84's and GE Rectifier. Anyone try EI tubes in this amp with any luck or tried changing the 12ax7 for another type? I have a few Mullard 12At7's I was going to try.