Which Class D Amplifier? PS Audio, Ghent, Nord, Merrill or other???

Technics SU-G30 has been around since spring 2016 according to the Technics website & contains GaN.

https://www.technics.com/uk/products/grand-class-g30/network-audio-amplifier-su-g30.html

So looks like GaN has been around for a few years & at £2799 for the SU-G30 it seems to be already filtering down to the more affordable end.

Has anyone here heard one?

I have not listened to the Technics SU-G30 yet. By reading the product page, it is evident that this is a fairly complex device, and that GaN transistors are a small component of the overall design. It is outwawrdly not possible to draw definite conclusions as of the relative contribution of GaN to the performance of Technics SU-G30

　

Worth pointing out that GaN transistors are not particularly new. Prototypes have been demonstrated as early as 1993... That is some 25 years ago. GaN-based transistors have been commercially available in one incarnation or another since 2006. See:

　

https://en.wikipedia.org/wiki/Gallium_nitride

　

Nor GaN are the exclusive domain of Niche companies: major semiconductors fabs, such as Panasonic Industrial Devices, offer Gan transistors and GaN-based assemblies:

　

https://na.industrial.panasonic.com/products/semiconductors/x-gan-power/power-devices

　

Relatively novel is only the application of Gan to high end audio amplification. If more amplifier designers adopt GaN, The next couple years will tell if transistors based on some forms of GaN inherently correlate to class D modules and circuits that contribute to enhance the audible performance of power amplifiers beyond the current state of the art. Or if the advantage afforded by the application of this semiconductor technology is purely a theoretical one. The danger of overoptimistic disconnects was nicely expressed by Mr. Berra:

　

"In theory there is no difference between theory and practice. In practice there is."

Yogi Berra

Regards, G.

Hello toetapaudio
What are your impressions about NAD, Gato, Nord and Mola Mola class D Amps?
Which ones did you like the most? 

Yes, personalities abound in these forum threads. And yes, folks have what one might call “signature statements” that amply showcase their strengths and faults. 

From what I can tell reading posts is that not a lot have actually personally heard this newer GaN-FET tech implemented into a class D audio amp design. So while the likes of AGD, Technics and Merrill might in principle sound terrific based upon this newer tech based upon the tech’s inherent theoretical advantages, they may also suck in real world implementation due to other designs flaws.

I’m not saying that they do suck and that the older MOS FET tech operating at lower switching frequencies are still king of the hill in class D land. But one ought to be careful in proclaiming one design implementation dead based upon merely theoretical considerations of a newer FET tech design. 

ricevs,

     A few of us here on Audiogon, myself included, have crossed paths with georgehifi and some of his dubious statements/theories about the current state of good class D amps utilizing MOSFET transistors.
       I understand your frustration since I also understand, based on using multiple good class D amps in my system for several years,  that I completely fail to detect any of the sonic shortcomings that georgehifi claims exist on my amps due to traditional FET transistors, the switching frequency being too low and the filter used to remove this switching frequency being of poor quality.
     Now, I just picture him walking aimlessly around an Australian city in a bathrobe and slippers, having just walked out of some institution attempting to treat his rare condition, continuously mumbling to himself phrases such as " switching frequencies too low!" and "better output filters needed!".  Occasionally, he stumbles upon an internet cafe and places posts on Audiogon.
     As I see it, however, the truth is that these new fast GaN FETs do have the potential to even further advance class D performance.  Perhaps higher switching carrier frequencies will be beneficial, too.  I think it's important to keep an open mind.
     Overall, I'm suggesting it may be best to just cut georgehifi some slack.  While he may be clueless on how good current class D amps with traditional FETs have become,  he oddly seems to have some good ideas on how to potentially make them even better.
Love,
 Tim