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?


128x128Ag insider logo xs@2xcelander
1)  The Man Said,
 "Not to mention Class D is most efficient and runs cooler so you save on power bills" Can you save on your heating bill with Class A? (just kidding)
2) I wonder if some of these effete HEA manufacturers use price as as way to convey quality rather than cost of production. I can't imagine some manufacturers pricing a monoblock  at $1999 even if they could easily make a profit. It would put them among the unwashed lower classes and damage their image. But maybe I'm getting too cynical. 
3) I used to buy radiology equipment for hospitals. Anything I spent $35,000 for would have way more components, more expensive components and involve way more labor and R&D than could possibly be put into any amp. They are sold to a very limited market and have to be FDA approved, which costs many times more than RFI certification. But maybe I'm too cynical.
4th and most relevant) I am a big fan of Class D and fervently hope that I will have the opportunity to hear a GaN based Class D product that I can afford soon. 
Ric, Ralph, anybody: can you explain the difference between Ice and Ice Edge modules?
The ICE Edge is their latest stuff- integrated high and low side drive circuits, optimized dead time, higher speed, higher voltages (for more power) and so on.

The Van Alstine mono blocks are pure balanced bridged amps.  They have xlr inputs.  There is an option to have rca jacks as well, but then it has a single ended to balanced circuit inside to then run balanced to the amps.  The amps are fully balanced.  As far as junk output jacks.....so what?  What matters, is the sound.  Now, if I tweaked the Van Alstine amps I would use my binding post bypass system and other tweaks for even better sound.  Are we so cynical that we think the reviewer was paid to say this and actually prefers his Merrill?  How does he get clout when reviewing a no name amp that looks like a black box?   Looks pretty genuine to me.  Buy, you never know.  But two reviewers in the same magazine using different systems are saying the same thing.  Pretty convincing.

I assume they are balanced as they are monos, but the picture I saw from the link, no XLR inputs?
ric, I offer you Tony Cordesman, who never reviewed a bad product,.. worthless reviewer for the consumer

Most reviews are worthless, unless they have mucho comparisons of the latest same money gear and show the gear being used. We are all in the dark. We are kept ignorant unless we A/B in our homes. Let’s say you wanted to spend $20,000 on an amp. So you read online for 2 weeks straight on every site and decide the 10 best possibilities. So, you arrange with dealers and manufacturers to buy all these amps with 30 day money back guarantee. So, you put out $200,000 of your own money. Of course, this all depends on them arriving at the same time and every dealer and manufacturer being OK. Of course, you do not tell the manufacturers or dealers what you are doing....or very few would go along with this. You listen every weekend with your buddies to all the amps and then keep the best sounding one for your system and send back the rest to get your money back. Once you have received all your money back you go onto a forum like this one and tell everyone what you discovered. Now, everyone who reads this will have an idea of what all those amps sound like and at least not be in the dark. Of course, once you posted your results then you would be person non gatis to some of those dealers and manufacturers. Of course, this is why this would never happen in a magazine. If they did this the losers would never advertise again and the magazine would go under.

You must realize that most reviewers do not get paid and their only perk is to get gear at 50% off. They don’t want to bad mouth an older product or they could cut off that manufacturer from every sending them another product. Check out this review of the Merrill 118: http://www.enjoythemusic.com/superioraudio/equipment/1018/Merrill_Audio_Element_118_Monoblock_Amplif...

He never mentions his "reference amps" and at the bottom he only give is 4 notes on several catagories (so he knows there is more to be gotten there).....but he does not tell us what amps do those qualities better. So, we can gleam that it is a great amp....but how good. There are no comparisons at all that have any meaning. Typical review......we are left in the dark, once again.

These reviewers are not bad people....they are not on a mission to get all your money and send you to hell. They are just people, like you and me.....but, because there is money and survival that goes along with this, they withhold information.

If you want to buy a $30,000 car you read online for a few weeks and then go test drive all the cars you want and then buy the one you want. Don’t you think it should be the same with audio? Where can you test drive audio gear.................................only in your home. And it is not easy, unfortunately.

By the way, have you ever noticed that car and camera gear, etc. reviews do not hold back any info. They tell you which ones they like and exactly the differences (measured and subjectively). It’s only subjective audio reviews that tend to be secretive. There are no measurements to tell you how they perform, so we must keep it all secret so you keep buying our magazines......not exactly evil....but sad. The original Audio Critic magazine bought all the audiophile preamps they could and did a complete review of all of them at the same time. Of course, back in 1979 or whenever that was, there were not that many products. What is really interesting is not just that no one ever did anything like that again, but that the owner of the magazine started to push his own speaker and then started to screw his readers. Then he became an "objective" audiophile and went 180 degrees......just a little old drama for you.


@ricevs this is what I’ve been trying to get at in one of my other posts here. “One amp to rule them all...”

we need a lot more of our language  codified when talking about audio gear, a lot more.

Back to what this thread is about, and that is GaN technology.
Here is an interesting read from EPC the inventors of the GaN Fet and what it can do because of it's ability to have a much higher switching frequency as in the Technics SE-R1 and I believe the Merrill's now as well. 
https://ibb.co/mqg829t

Cheers George

Anthony Cordesman and myself share the same birthday, 20 years apart. Anthony is a classy audio gentleman unless a drastic change has happened over the years. Over the years he has added a sense of style to our hobby and in my book is one cool dude.

Hi Anthony, hope you are doing well!

Michael Green

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Common guys, THREAD MISDIRECTION????

I’ll jump in before the OP does.
This thread of celander ’s is supposed to be about Class-D and GaN Technology, keep it on topic. If you want to talk about worthless reviews, Van Alstine’s amps PM each other.

Back to what this thread is about, and that is GaN technology.
Here is an interesting read from EPC the inventors of the GaN Fet and what it can do because of it's ability to have a much higher switching frequency as in the Technics SE-R1 and I believe the Merrill's now as well.
https://ibb.co/mqg829t

Cheers George
blindjim2,801 posts
  I heard the Merrill Element 116s recently. albeit all too briefly. I've been around long enough to know when I'm listening to something special though and quite immediately.
I found his setup overall to be spooky good

Taken from another thread by a long term member, this bodes well for the Merrill amps using GaN technology.

Cheers george
I would like this thread to remain on track to the topic set forth in my original post. I started this thread because I felt that other class D amp threads often only touched tangentially upon this new GaN-FET technology.
Everyone has the power of the pen. Please start your own thread about other amp technologies or designers thereof. Please don’t waste your penmanship here with those topics unrelated to the topic of this thread.
This is a side note to the Class D and cool running amps. 

One of the major benefits of running cool or cooler is that the components stay intact longer. A major benefactor of this cooler running amp it the Electrolytic Capacitor that is very common in power amps. The electrolytic capacitor offers higher density, higher voltage and higher capacitance for the size and price. A large number of capacitors and large capacitance is used for the power regulation, even if most of the regulation is done by semiconductors. 

The drying out would typically run about 20 % less after 10 years.  Heat accelerates the drying out of these capacitors reducing the performance faster.  One hopes electronics will last a few decades. Cooler running equipment have a better chance of this occurring. 

Of course, first and foremost are sonics. And it will have to start off very good to have this as a consideration. 
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merrillaudio

I have to say, I was excited to hear your amps (driving Muraudo speakers) at the Florida Expo, but I had to leave the room fairly quickly. The tonal balance was awful. Thin, edgy, lacking in body and natural overtones. I commented about this in another Class D thread and another member chimed in saying he heard the same thing with the Muraudio Speakers at CAF, driven by Triangle Art Class A monos. I'll just say I hope to hear your amps in a more synergistic pairing in the future.
It’s too bad that Merrill (the man) won’t be in the mix at APOXNA 2019 in Chicagoland.