Now I am intrigued but I don't understand your design at all because I am schematically challenged. What are the new tubes doing that the old gas tubes were not, and how does the voltage pot idea work? i.e., wtf does this mean:
"It can be a dual section in which case both supplies adjust at the same time, or if you do it as 2 seperate knobs on the same shaft, you can adjust the front
end gain power supply seperate from the output power supply."
Thanks man, and I look forward to figuring this out.