Matching tubes by current draw

[dude]

Can satisfactory matching be obtained by just matching current draw, talking power tubes?


I have several 6V6s, various makes and have just used the biasing pot to find ones that match in current draw. Usually shoot for within 3 to 5 mAs draw.


Thanks,
al

[sluckey]

yes

[dude]

I figured it's good enough. You can find unmatched, untested tubes on fleabay for cheap, nice RCA, GE's (and some with other name brands that were made by RCA, GE etc. sleepers). I've had good luck just matching the current draw but there's always a tube or two that buzzes and the mA draw is way off. I've match a few pairs that were buzzy and wayout of range on my bias R, they almost always sounded weak and noisy, just toss them.


Thank for the quick reply,
al   

[PRR]

Satisfactory to WHO?

For High-Fidelity seeking *lowest* THD numbers, or for a tube limiter, you want close match ALL up and down the current scale, testing at something near your in-use voltages.

For a guitar amp, little wrong with a horse-and-mule combination.

[dude]

Ok, sorry PRR, I was talking about push/pull guitar amps.


I like the analogy to the horse and mule