Please read the review of the Technics system:
http://www.theabsolutesound.com/articles/technics-r1-reference-system/?page=2
What it says is that the Technics amp is not a class D amp......it is a digital amp. IE....it takes only a digital signal and then converts the PCM stream to PWM to drive the switching output stage. The "analog" input on the Technics amp goes through a 24/192 A2D converter to change it to PCM so it can then get converted to PWM.
Of course, the switching output stage is the same as class D but the way it is driven is far different. The Tact amp was the first (I believe) to do this. Of course, its switching output stage does use GaNs, so should be included here. But, not many audiophiles want their precious "analog" signal turned into digital.
So, right now the only analog input class D amps are the Merrill and the AGD. I asked Nuprime on their forum on Audiocircle if they were planning to develop an amp using GaNs........and they said it was in R&D.......and that they thought they were way ahead of most others. They thought it would take 2-3 years before there are any standard off the shelf modules available.
What is really interesting is that Technics claims that using just one GaN per phase is really important.....rather than a bunch of parallel Mosfets like the earlier IcePower, etc. Certainly the dead time can be kept shorter if there is just one switch per phase. Other newer class D amps have just one mosfet per phase also.....like the IceEdge modules. They also have "continuous dead time compensation (CDC)".......maybe these are reasons why it sounds so good?......sort of simulating the "GaN effect"? Of course, using GaNs would reduce the dead time so much you probably would not need to compensate at all and probably have even better performance. I have been talking to IcePower USA.....trying to get them to get into the GaN thang.........looks like inexpensive class D GaN amps are not in the immediate future. Since everything you do changes the sound, we need lots and lots of manufacturers working on this....so we can have lots of variety and hopefully way cheaper prices......right now its a $15,000 entry fee to get into GaNs. To rich more most of us here.
There is that esoteric hard to find 12 volt car amp that uses them.....I am trying to get info on it....seems like it sells for around $1200 but info is scarce (no info on the manufacturers website). I am waiting from the manufacturer for into. I will let you know what I hear.