Yep. That answers my question. I'm running the 12B4 through my Pi Two Towers as they are probably the most eff speakers I have, besides the old Heresy's which are about the same as the Pi's. My old Polk Monitors don't stand a chance. I don't tend to listen very loud (not nearly as loud as any of the demo rooms were running at GPAF) and so far the little amp seems to do fine at my usual listening levels. It'll run out of gas if I boost the volume up, especially with complex music. Limitations of flea powered amps I really want to try the small drivers you had at Tulsa with a sub sometime this fall/winter as a side project.