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Newbie bias voltmeter readings question

Just got a used Music Reference RM-10 tube amp direct from the manufacturer, Roger Modjeski. Hard to believe this is the third tube amp I've ever owned, but the first one I've ever had to bias (the others were self bias or auto bias). Actually, I don't have to bias it as Roger was kind enough to set the bias before he shipped it. Nonetheless, I want to everything I can about the amp and be able to keep an eye on the bias periodically. I went and got a Radioshack digital voltmeter. Roger indicated that he set the bias to 280 mV or 28 mA. When I took the readings, I got the 28 mA, but the millivolt readings were 30 to 40 mV higher, and read approx. 315 mV on each side. The question are: is the discrepancy in readings normal? Is the voltmeter inaccurate? Which is the most reliable readings to take, mVs or mAs? Any guidance in this matter is appreciated.

I'm sure there has been enough said about Music Reference amps, but if anyone cares to know, this amp is fabulous. Too premature to say definitively, but it may be the best amp I've ever owned (out of tube and solid state). Anyway, thanks again.


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Topic - Newbie bias voltmeter readings question - hartwerger 17:30:45 11/30/06 (3)


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