I've tried numerous tubes, after tubes after tubes without being content (something in the tone always bothered me, too little lows, too much presence, too muddy), and then finally today i decided to go back to my stock Mesa 12ax7-a's, and not so stock but older SED winged =C=nd there's my tone. I think it had more to do with putting in the Mesa pre-amp tubes. But after being a tube ***** for so long i just went back to what i was happy with long before i was a tone nut and there was my clear, yet aggressive tone. Loved it. Went full circle. I think i'm gonna replace those winged C's with Mesa tubes too. But these amps just react best with boogie tubes IMO. Just the way it is I think. That Edge and aggressive quality that i remember is back. And leads just sing!