What makes you say that?
Well, I've been noticing some power loss lately. The amp goes into overdrive faster than I'm used too. And I have to crank it up more to keep up with the rest of the band.
So I asked our guitarist's dad who is a retired airforce radio technician. He checked the tubes with a tester
and came up with the following results
0 - 40: replace
40 - 50: questionmark
50 - 100: good
Test results:
Tube I Tungsol: replace 20
Tube II General Electric: questionmark 45 going back to 42
Tube III General Electric: good 90
Tube IIII Tungsol: good 90
and
Buis I Vg2 = 392V VRg2 = 0,04V (Rg2 = 1KOhm)
Buis II Vg2 = 392V VRg2 = 0,07V (Rg2 = 1KOhm)
Buis III Vg2 = 392V VRg2 = 0,40V (Rg2 = 1KOhm)
Buis IIII Vg2 = 392V VRg2 = 0,90V (Rg2 = 1KOhm)
Depending on how they're arranged and biased, your sound may simply be suffering from phase cancellation. GE's are known for their midrange snarl, as are vintage Tungsols. Were they installed by a tech who biased and checked the output on a scope to see that it's symmetrical?
Yes that is quite peculiar to have two different brands. That's how I bought it (second hand of course). However the amp had been serviced by a professional before it was sold to me.
To get the amp in better balance, this means balancing the positive and negative phase of the signal in the power amp part, Frank's dad switched tube II and III.
But he advised me to go look for new tubes.
@ Kenny: shut up for once will ya