ken scharf wrote:


I really don't see any advantage in his circuit over a conventional zero
bias grounded grid amp, at least not with the 4-xxx series of tubes.
With the 4CX250 series it makes some sense since these tubes CAN'T be
run in zero bias grounded grid due to the fragile grid structure in
these tubes.
You only needed 20W of drive power and a single HT supply. I have one
using a pair of 813s, 10W from my TS-120 drives it to about 200W output.

It looks to be exactly the same layout as the one on Ian's site but has
had the valve rectifiers replaced with solid state at some time.

Steve H