• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Cathode Follower high power class B grid driver

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The goal is to drive the grids of a push pull pair of 3-500Z tubes in AB2. It can be considered a 600-900W audio amp.

Here's a little something simmering on the back burner for it. Back burner is OK because I'm doing perfectly fine driving the push pull 3-500Z output stage with a 5x oversized tube type power amp (AP-80) and swamping 50% of the actual drive in a load resistor. This gives most of the necessary voltage regulation and prevents most of the amplitude distortion, which is an issue when moving drive into a grid current region.

So, the purpose of the driver circuit is to get even closer to the goal and remove the need for the aforementioned rack-monster external amp.

There is more work to be done, it's very preliminary based on a 1955 article. Not all the stuff shown may even be needed (metering etc.) and a self balancing or self biasing system would be good.
 

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