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RE: Too low plate R value for a triode ? and CCS substitution?

Posted by Tre' on March 22, 2017 at 21:53:47:
"However the plate resistor is only 1250 ohm which is less than 3 times of 420 parallel section of 6h30."

That helps me understand a lot about a back and forth thread I just had with Victor.

I would never build that way.

If the output swing is low it might be just fine but I run tubes in the most linear way I can, regardless of needed swing.

I think it sounds and measures better that way.

The rule of thumb I use is, "the load impedance for a voltage stage should be 10 times the plate resistance minimum, 20 times is better".

That keeps the load line fairly horizontal and the harmonic distortion low.

Tre'