Class D

because of my obsession with GaN with it’s ability to have 1.5mhz switching speed the Achilles heel of Class-D

This really isn't correct. You can get vanishingly low distortion with less than half that speed; alternatively you can go a 1.5MHz using MOSFETs as they are plenty fast enough.


GaNFETs have other advantages completely unrelated to their speed, although you can run them with slightly less deadtime. The thing is, if you run at 500KHz, the deadtime (being a constant) has 1/3rd the significance that it has at 1.5MHz.

Douglas,
I hope this tease of yours dies quickly.......What is this mysterious class D amp that you love?  Is your mouth tied shut till the review?  he he....If you absolutely cannot tell us more.....then when is the review going to be published?

Exogal?

ricevs, I'm just ebullient due to the performance. Forgive me, I won't talk about it anymore.  ;)   The article should be coming sometime in the first quarter of 2021. Still some important system building to do for an attempt at ultimate build, performance, etc. 

No, it's not Exogal. However, I am using the Exogal Comet DAC with it a lot, with spectacular results. 

I did not hear anything from the Gan amps at AXPONA that would make me think they are superior to the one I am using.

I believe you would have, if the one/s you heard used the GaN technology to it’s fullest, which is to be able to increase the switching frequency 3 fold to 1.5mhz like Technics did with the SE-R1 and maybe in Feb 2021 the SU-R1000.
Then the "switching noise output filter" can also be set higher and so eliminates most of the switching frequency noise left at the speaker terminals. Without introducing phase shifts back down into the audio band, like what happens with lower 600-800khz switching frequencies/filters.
EG: in red https://ibb.co/vvwzGV5

Cheers George