Biasing - Carr Rambler Amp Owner's Manual

Biasing your Rambler
The Rambler is a cathode bias (self bias) amp and as such does not require a bias adjustment
when changing tubes. Please use well-matched pairs of output tubes for maximum
performance and minimum hum in Triode mode. The Rambler can only use matched pairs
of 6L6, 5881, or 7581A power tubes.
Carr Amplifiers selects and tests the finest current production tubes specifically for each
amplifier model. Caution should be used when buying replacement tubes from any dealer
who does not have a return policy as all tubes can have problems (NOS tubes are
susceptible to microphonics and failure too).
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