In Reply to: RE: If you need precision current bias of power tubes... posted by 6AS7_6SN7 on June 4, 2017 at 10:58:18:
"A current source does not suit so fine in a (PP) power output stage.
Tube rectification always occurs when leaving class A operation and spice simulations show that a capacitor in parallel to the 'current source' (or the bias resistor) reduces total harmonic distortion.
"
If you configure the output stage as a LTP with a current source "tail" it never leaves class A. Granted, matching tubes is a "bitch" but it can be done. Sonically the result can be quite surprising for those who have never heard it before. I'm currently running four triode connected KT-120s in PPP off of a single current source @290mA.
"It is better to remain silent and thought a fool, then speak and remove all doubt." A. Lincoln
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Follow Ups
- RE: If you need precision current bias of power tubes... - JKT 14:39:25 06/06/17 (1)
- RE: If you need precision current bias of power tubes... - 6AS7_6SN7 07:53:45 06/08/17 (0)