My favorite amp I have is my TR SP 22...love love LOVE this thing... I've read on so many places where great NOS glass makes such a big difference in amps. I've got GAS for SOMETHING, so I thought I'd start this thread and try to cure my gas with tubes (maybe it will cost me less than a new amp or guitar, or pedal(s)!) I've got several new tubes I've tried in v1, trying to calm down the low end - and I found that a, believe it or not, JJ 12ax7 seems to do the trick. The stock Tung-Sol gives this thing so much body, it almost takes away from the clarity (to my ears - I know that can be part of the endearing tone) I'd love to hear what kind of tubes, both preamp and power, some folks have swapped with success. Before and after clips are a HUGE PLUS. This may end up being a 5-8 post thread, and that's cool as this is kind of a niche amp, but if you're out there and have done it POST. I remember only ONE guy from the past, that had a pic of his SP 22 and a guitar next to a window/sliding glass door that had done this, but I can't find the post or the results he had. Maybe you'll stumble in here?