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.
Digressing, wonder if anyone has tried Schade feedback with these, perhaps 400v on the anode is possible with 250v on G2, but maybe the kink will be an issue.