animal69

That seems high for me, try this approach. 1. Lower the valuue to about 28ma, then from there raise it a little, maybe 2ma play it for a while and see how you like it. Raise it another 2ma to 32ma and play it again for a bit. Try to keep it below 36ma. For me when biasing amps every amp I have ever used gets to a point where it starts to thicken up sound wise, I almost with out fail like the amp set slightly below this point. This is usually middle to slightly cool for the tubes, biasing tubes to the point where they almost red plating is a dumb ass approach IMHO and does nothing to help your tone. Yes this is what I did. I get my dirt from a great overdrive pedal so I don't like the idea of my Twin breaking up at higher volumes, I like the chimey clean sound. I set it at about 29mA. This gives me a nice clean sound up till about 5. When the volume is past 5 it doesn't make a difference anyways, the current jumps all over while playing (up to 80mA). So I think biasing cool really gives you more options since the current will run off and do its own thing when the volume is cranked.

I just got 4 JJ 6L6GCs for my Twin Reverb. I've done biasing before. What bias current do I want for my 6L6GC power tubes with the Twin Rever? The Weber bias calculator*, at 445 measured plate volts, suggested 47 mA but my amp wont let me go above 45 mA. The Weber site assumes the power is 30W for the tube. Since the Twin reverb is rated at 85W, do I want to divide 85 watts / 4 = 21.25 W for the wattage for each tube, divide 21.25 number by 445 and then multiply by .7? This gives me 33mA. http://www.webervst.com/tubes/calcbias.htm