BHK Pre - some pre-buy questions

[brett66]

BHK test and answer here:

BHK Preamp tube rolling

Johnny said Thanks B! Appreciate the help and the insight on CCS/cathode in regards to the differential circuit… Really hope the regulator can handle the increased load because the 6N6P sounds really good, just don’t want to leave it in without knowing long term effect… when looking around I did have on a short list the 12bh7, 6cg7/6fq7, 6gu7, etc… to try,… all of which can be bought cheap… comparatively speaking of course, and have suitable load lines… Best, Well, I took my p…