Regarding the Sovtek inverter tube and the difference between it and the JJ which the amp came with (and unfortunately which showed up DOA):
I also went gushing on and on about how great an amp it is and his response was:
"Check your bias. Should be between 36-40. Adjust by ear in small difference. Bias test points under chassis. Set multimeter to dc volts."
It's really hard to get a picture of a band in performance which includes everyone.
"It's one of the most incredible circuits ever. True definition of classic. Best part is, you can drop 6L6, 5881 or EL34 tubes in there with a rebias. (FYI, el34's change the speaker out ohms...email me if you decide to ever do that)."
These are important notes for me to retain. Keywords are "bias", "rebias", "Edana", "tube".