MESA BOOGIE EL34 STR447 Grey AC 10 Power Tube TV7&Maxi Tested NOS ¥
Mutual Conductance (GM)Test: 40 (46 = NOS AVERAGE & 30 = Good MINIMUM). Test results will vary between testers as it is not an exact science. I also use variac at 120 volts with my testers. Plate current: 40.5 MA.