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RE: Octal base driver for 300b

Posted by sideliner on August 25, 2020 at 18:11:37:
>>I'd prefer a low bias voltage to avoid a cathode bypass cap if possible<<

Leaving the cathode un-bypassed will raise the tube's plate impedance significantly. While this might be okay for a voltage gain stage, it's not a very good idea for a tube acting as a driver and even more so if it's driving a DHT. I would reconsider that idea if I were you.

A good 300B driver tube that's been used by quite a few is the 6N7 where the two sections are run in parallel.