Hey amp gurus... My recently finished Dave Hunter Two-Stroke (classs A, single ended) is running 420v on the plate (pin 3). Cathode (pin 8) is at 19.5v, for about 400v actual plate voltage (pin 3 minus pin 8). The amp is cathode biased. While it sounds stellar, I'm just worried that this is a little too much voltage. Do I have anything to worry about, and should I try to lower the plate voltage a bit? Or just crank it and enjoy? Thanks!