Mike Gilmour wrote:

Fixed bias? with bias adjust pots I would expect the cathode resistor
to be lower at around 10 to 50 ohms. But I stand to be corrected :-)

I ain't no expert, but I believe it's the voltage that counts. :-)

I'm assuming his outputs are push-pull, and not too dissimilar to my
nominally-20W AB1 amp, which uses 470R (no trimmers). My 50W guitar amp has
a bias supply (cathodes to ground), and the schematic specifies -32V at the
signal grids. If Keith's amp is higher o/p than mine (40W, Keith?), maybe he
should be looking for something like 30V?


--
Wally
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