IMHO, there really is no reason to match power tubes in a guitar amp circuit. Just buy a matched set from a repuatable dealer. I've heard some techs say that guitar amps sound better with slightly mismatched tubes (5-10mA). Besides, Fender used to just grab two or four tubes and stick them in the amp and called it good. They didn't worry about matching. Although at the time, RCA Blackplate tubes were readily available and they were made to much tighter tolerances than modern production tubes.Originally Posted by duhvoodooman
The only advantage I can see for the individual biasing scheme is if you have two tubes that are way mismatched.
Also keep in mind that the individual tubes do age differently, even ones from the same batch.
tung