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Self defense

In recent shenanigans on this forum about bias classes I noted that Self preferred something he called optimal class-B where bias is adjusted to give the smallest perturbation as you cross between pull and push but I didn't know what that equated to in terms of bias current (for a complimentary emitter follower stage). My interest reignited I obtained a copy of his Power Amp design book and have been working my way through it. As chance would have it, today at lunch I was at a section where he showed such numbers and an optimal bias turns out to be in the 100mA to 200mA range. He finds the optimal bias should set by the voltage across the emitter resistors and not by the current through the followers (and the optimally biased current is much lower when using complimentary feedback pairs instead of followers). What is very interesting is that he shows how the output stage small signal gain changes from under-biased to class AB along with the corresponding distortion residuals.
In Self's defense I think it fair to say he does know the difference between bias classes and he shows that there will always be cross-over distortion in a solid state push-pull output stage even if it is very small.
I know little about tubes but I find it difficult to believe that turning one off as part of a push-pull hand over does not create some discontinuity and I boldly, yet respectfully suggest that if you haven't seen it you are not looking hard enough.

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