This is a corollary to my 'Bogen PA --> Bassman' thread. I've tried to figure this out, and it's time to ask my forum friends here. I'm not sure how to determine the current portion of the calculation for resistance value and wattage rating of needed dropping resistors along the power rail. I absolutely need to be able to do this to get the right plate voltages to the right places. Varying articles (on the Online) say to add up the current draw for tubes 'upstream' of the resistor. Common assumption seems to be 1.1 Ma for 12aX7 triodes. For power tubes, though, "current draw" for calculation purposes is unclear to me. If it's "plate current" on the data sheet then I'm confused. Looking at the GE 6L6 data sheet for two tubes in AB1, idle plate current is 88ma at 360v and 116ma at 450v, and maximum-signal plate current is 140ma at 360v and 210ma at 450v. Which current number to use..? And, if my amp's B+ is closer to 500v (which it might be), then what..? Even better, can you run through an example for me -- say, using an AA864 schematic (link). For purposes of calculating the values (resistance/needed wattage rating) of each of the 1K/1W and 4.7K/1W dropping resistors (if we didn't know them or, say, needed to adjust for high/low B+), what is the 'current' in the R=V/I equation? Thanks for any insight you'd care to offer.