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Re: Biasing 6550s??

Posted by steven oda on September 25, 2002 at 22:42:02:
Ty,
Marshall put about 395 volts onto the anode plates of the 50 watt series JCM 800 and 455 volts on the plates of the 100 watt JCM 800 lead amps. Both loaded with 6550's.
For the 50 watter: at 395 volts bias to around 60mA.
For the 100 watter: at 455 volts bias to 53-55mA.