GaN-based Class D power amps


The use of GaN-based power transistor tech is now emerging for Class D audio power amplifiers. Seems appropriate to devote a forum thread to this topic. At least 3 companies have commercial class D amps in their books:

Merrill Audio, with their model Element 118 ($36k per monoblock, 400 W into 8 ohms, 800W into 4 ohms), Element 116 ($22k per monoblock, 300 W into 8 ohms, 600W into 4 ohms) and Element 114 (coming soon). 
https://merrillaudio.net

Review of Element 118 at this link:
http://www.enjoythemusic.com/superioraudio/equipment/1018/Merrill_Audio_Element_118_Monoblock_Amplif...

ADG Productions, with their Vivace Class D amp ($15k per monoblock pair, 100W into 4 ohms). (The designer emailed me indicating he has another product in the pipeline.)
http://agdproduction.com
Review of the Vivace Class D moniblocks at this link (warning: link might not work (1/11/2019)):
https://positive-feedback.com/reviews/hardware-reviews/agd-production-vivace-gantube-monoblock-ampli...

Technics SE-R1 Class D stereo amp ($17k per stereo amp, 150WPC into 8 ohms, 300WPC into 4 ohms) 
https://www.technics.com/us/products/r1/se-r1.html
Preliminary review of the Technics SE-R1 at this link:
https://www.stereophile.com/content/technics-se-r1-digital-amplifier
Technics also has a lower priced GaN-based class D integrated amp in their catalog:
https://www.technics.com/us/products/grand-class/stereo-integrated-amplifier-su-g700.html

Anyone listened to or own any of these amps?


celander
The quality of sound reproduced by the audio amplifier, measured by THD (Total Harmonic Distortion), DF (damping factor), and IMD (inter-modulation distortion) is influenced by the characteristics of the power transistors used.eGaN FETs’ near ideal switching performance due to lower propagation delays and faster slew rates (due to their lower gate capacitance) and zero QRR enable very short dead times to provide lower open loop distortion, lowering the THD and overall losses. This reduces feedback, driving down T-IMD and DF to provide a step jump in the sonic quality of Class-D audio amplifiers and lowering overall losses

Everything I've been telling you about reducing or eliminating dead time is in the above statement from the pdf you linked, quoted above.

They are so cheap now its hard to imagine why someone would not use them.

I’ve been telling you about reducing or eliminating dead time

I’ve never denied it, and have said it’s also a bonus with the GaN technology, and as I’ve always harped on about is the switching frequency giving better sound if used at 1.5536mHz so then output filter is not in contention as stated by Steve Colino of EPC designers of the GaN technology, and finally we’ll get to see bench test square waves that look like square waves like linear amps can do, and not like timber mill buzz saws .

But it can also be done without heatsink if the switching frequency is used at 400khz as stated in the other pages of the the pdf I posted.
Quote: " 200W per Channel into 8 ohms • 400W per Channel into 4 ohms. 96% Efficiency Reduces Heat and System Size • No Heat Sink Required"

Affordable Amp manufacturers will not "use" the raw GaN fet component, only the more esoteric $$$$$ ones may design their own modules, if they’re suicidal.
Most will wait till new OEM manufacturers like IcePower, PowerSoft, Hypex, Sangway, Tripath ect ect make them up using the GaN technology, so then it’s easier/cheaper just to put the complete module in a box with a power supply.
Let’s try to keep the hyperbole and slams against manufacturers to a minimum. Let the market dictate success without besmirching designers who opt to take a different path than those who endorse module users. 
celander who's slamming who!! please read and absorb? (remember forest and trees)

Cheers George