Express build finished with PPIMV - cut control and NFB advice needed!

[Mark]

Is the PPIMV really worth implementing, I thought the joy in these amps was pushing the output valves, though I imagine a fair component of the overdriven/distortion is from the PI stage.

I recall that katopan showed that a significant part of the overdrive character was the output valves sagging the HT supply to the LTP. And another significant part was the output valves clipping the output from the LTP.
Both of these mechanisms would be absent with a type 1-3 master volume.

I built a two EL-84 Liverpool and I found the supply to be quite solid, I found the choke resistor was dropping the preamp/PI voltage by 40VDC.

I found the amp stayed quite tight and the top end softened as I turned the amp up. The power transformer was about right for the amp, but the output transformer I used left something to be desired. I wonder what would be a good output transformer for 15 watt Express or Liverpool?

[pdf64]

… I built a two EL-84 Liverpool and I found the supply to be quite solid, I found the choke resistor was dropping the preamp/PI voltage by 40VDC…

As that’s a modified version of a different amp design, I think that would best be looked into as a separate case.
Sag in this context usually refers to a drop (eg in a power supply voltage) between idle and full output conditions.