So I posted this on the Weber forum, but thought I'd double it here too as I find this forum super helpful and insightful. I built a Phat Ass off of the weber forum, actually my second. But this one was a cathode biased el34 version. I feel like it is lacking in the ummmph section. Pretty much clean, not a lot of power or spank. Maybe something is wrong, but everything seems to measure out about right. I was thinking about changing out the preamp to something else. Or modding it in some fashion. Like I said, it is a cathode biased el34 pair, being fed by a ltpi with a ppivmv. I don't get much breakup until the thing is pretty much cranked and my guitar volume is on full. My traynor ygm3 with a fixed bias el84 pair walks all over this amp. What should I do, trying to retain the power section/phase inverter? Not totally opposed to adding another 12ax7 if I need to. There are two as of now.