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RE: Class B does not have to have a zero crossing artifact.

Posted by morricab on February 12, 2025 at 06:57:19:
It's inherent in how transistors are non-linear in turn on and shutoff. Here are many examples of even so-called Class AB that have zero-crossing distortion. If you don't put enough bias then it is guaranteed to be there.

https://www.stereophile.com/content/jmf-hqs-7001-monoblock-power-amplifier-measurements

https://www.stereophile.com/content/plinius-reference-150-power-amplifier-measurements

The Class AB mode for this amp has zero crossing distortion and the Class A mode does not.

https://www.stereophile.com/content/naim-classic-200-series-nap-250-power-amplifier-measurements

https://www.stereophile.com/content/infigo-method-3-monoblock-power-amplifier-measurements

https://www.stereophile.com/content/karan-acoustics-master-collection-powera-mono-power-amplifier-measurements

https://www.stereophile.com/content/dan-dagostino-master-audio-systems-progression-m550-monoblock-power-amplifier-measurements

https://www.stereophile.com/content/sae-2hp-d-power-amplifier-measurements

https://www.stereophile.com/content/audio-alchemy-dpa-1m-monoblock-power-amplifier-measurements

https://www.stereophile.com/content/plinius-audio-sa-103-power-amplifier-measurements
Again, AB has zero crossing distortion and Class A doesn't.

https://www.stereophile.com/content/class233-ca-3200-three-channel-power-amplifier-measurements

As you can see, many modern amps suffer this problem even ones called Class AB. Probably only the Naim would claim to be Class B.