20/20 dismatched ???

[disassembled]

I would just measure the voltages at on the tubes to see if they are both receiving the same voltage and to make sure the bias isn't way off on 1 side. Also, you should put the old tubes back in to see if maybe you have a tube problem. Check your screen resistors too (make sure all the tubes have that nice blue glow when operating)

I have different speakers but even then my knobs are pretty close , although not exact, when it comes to matching volumes.

Greg