76.90.39.24
This Post Has Been Edited by the Author
In Reply to: RE: That's not correct posted by Audio Pete on June 15, 2017 at 14:44:08
The "2" has nothing to do with where you bias the tubes.
It has to do with how hard you plan to drive them.
When the driver stage is up to the task you can drive the output tubes into grid current (grid positive WRT the cathode). That's the "2" part.
"With the tubes barely on" is Class B (or at least what they call Class B).
The "barely on" part is just to keep the notch distortion down.
True Class B (rarely used for audio) is when the tubes are both in cutoff (not just in the cutoff region but in real cutoff ie; no current flowing) in the absents of input signal.
Now, just to start a flame war, in true Class A the tubes are never allowed to enter the cutoff region (the region approaching cutoff where the linearity of the tube goes to sh_t or the non-linear region close to saturation).
Class of operation is more than just the bias point. It's how the tube is biased, how the tube is loaded and how hard the tube is planned to be driven.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Follow Ups:
Top of Page ]
[ Contact Us ]
[ Support/Wish List ]
[ Copyright © 2017, Audio Asylum, all rights reserved ]
[ Take5 ]