complaint is red plating, has some Sovtek 6L6 tubes, OEM tubes were 7027's,
RCA says you can squeeze 76 watts out of a pair in push-pull AB class,
but you need 540 volts and 100ma of idle current to get there,
a 6L6 will take a little punishment, but not for long, especially at 540 B+,
what do we do? get the guy to spring for a quartet of JJ 7027's at 22 bucks a pop?
they plug right in, 6L6 and 7027 share about the same pinout, Ampeg wired this amp to take both,
only way to drop the B+ is by changing to choke input which does not sound that great, or dump the voltage as heat thru resistors which is a primitive fix at best,
there is another solution....
cathode bias!
through in a couple of 270 ohm 10 watters in parallel and you can make the tube think that it is seeing 40 volts less B+, or around there, you get a nice compressed sound that can make a solid state rect amp sound like it has a tube rect, which is what we need to get the 6L6 to have as much mojo as the 7027,
ask somebody why they don't use cheaper 6L6 tubes in this amp and they say if they wanted that sound they would have bought a Fender, but have they heard cathode bias? probably not, Fender quit using that back in the 50's on that 5881 equipped Bassman,
another benefit of cathode bias is that these amps are notorious for getting the sound guy to ask that you turn the amp down, so everybody runs them with the volume set on 3,
with cathode bias, we can get the club owner to let us set the volume control to maybe 7?
we will see...