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RE: your statement still isn't logical.

You never demonstrated anything of the sort. You simply stated that some old Class B amp you knew of didn't have zero crossing distortion.

Last time I checked, your statements are not factual proof of anything.

Show the measurements of the amp in question. Demonstrate how it is possible for a Class B amp to not have zero crossing distortion when it is clear that the transistors are going into cutoff and it is highly non-linear. The disjointedness of the handoff between transistors in Class B, where one is going into cutoff and is non-linear and the other is also non-linear (but with a different transfer function in that region) upon turn on is inherent in the devices and the Class B bias.

The amps that are Class AB and showing zero crossing distortion are ones where the bias has been set too low and they are not completely eliminating the zero crossing distortion as the transistors are now in a quite non-linear region of their transfer function. You can call this poor design if you want but it shows clearly what happens when the bias is set too low...exactly what you get in Class B.

What design trick could be made to eliminate the zero crossing when biasing an amp Class B? Oh wait! I know, bias it in Class AB or Class A! If done correctly it will eliminate or mostly eliminate the issue. If there was a better way to do it then I think you would see most amp makers doing that because you can of course get away with a smaller power supply because of the very low power consumption on idle. So, please spare me your "what if the designer has a way around the issue"...that way around the issue is to build a bigger power supply and bias the transistors with a lot higher quiescent current. Negative feedback is not the solution to this particular (or any really) problem with amp design.

BTW., one of the amp measurements I showed was a Naim amp. Not surprisingly, it has zero crossing distortion because...it's Class B!

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