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?


Previewcelander

Showing 50 responses by tweak1

karlsn2

Congrats. Even these AGDs are not cheap for most of us

Im hanging in there in high anticipation of receiving my Voyager, BUT, in the mean time, I did a couple simple things to my EVS 1200 that has dramatically improved it. Although Ric the designer extraordinaire recommends adding weight to the top of all components, I find that doing so dulls the leading edge and muddies the sound stage.


First, I removed the 2.5 pound divers weight I had placed on the EVS 1200 to an aha moment, then decided to remove the top cover to a OMG moment. The entire noise floor dropped revealing a much more 3D sound stage that now reveals even micro-detail. Some will think this analytical, but if it's on the recording, I want to hear it
LOL,


No one is more anxious than I am, but less so now that I have released the 1200 from it’s confines

I waited 4 months for my 1200, which was/is NOT a ground up amplifier. Every electronic aspect of the Voyager is a ground up. Lots of R & D changes were necessary before final release. This is much like the many tweaks you made to the 1200 prior to its release

As soon as I get mine I will be posting about it as I did with yours. Hell, Im still waiting on my 2.8s which I suspect will make the 1200 sound even better than it already does


My bad, 8 weeks, like that's timely when I paid in full in advance? I never would have agreed to that had I known you were not prepared to ship in reasonable time

How many times do I need to say when I get it, I will post it?
jetter,


as much as I love this amp; moreso after taking the top off and removing the BS Kubes he forced me to buy or he would not sell it to me, or anyone! it would not have broken MY heart.


I knew full well that it would likely have little resale value, but with the many years of experience with class D I was willing to take the risk, but not had I known it would take Ric so long to build it and ship it. Would you?

and why does he keep asking me about delivery? I asked him many times how much longer, he never gave me a date


Ric, I just sent this to the mods


According to Rics post in the GaN thread he is in declining health and will no longer be making the EVS 1200 amp. In the GaN thread he said he wished (MY THREAD): Life with RIc Schultz EVS 1200 could be removed. I said it would be OK with me, and suggested he contact you himself, but his health might slow him down from getting around to it

As long you're not going to make any more of them contact the mods to see whether they will remove the EVS thread
Im ok with it as it would then serve no purpose

As to putting me ahead of others, that was a wise business decision. I created a lot of buzz for you. What wasn't a wise decision is that you decided to stop production (as it were) until I reported on my Voyager. I kept asking why as the Voyager was to be only 100/200 wpc, no match for a powerhouse 600 wpc which many people need. Maybe that was an excuse due to your health

As far as I know only one other 1200 owner posted to my thread
Sorry about your declining health. I lost Clark Johnsen about a month ago. He was an annual visitor to my home for many years. For those who didn't know of him, he wrote for Positive Feedback, wrote The Wood Effect, an extensive essay on Polarity.
Let no good deed go unpunished (I had Tammy take down my Life with thread for you.) And this is the crap, er thanks I get?

Passive Aggressive talk: "you keep making things up" ..." speaking the TRUTH. Your soul will grow if you speak the truth. "We ALL lose when you don’t." Thank you, you are beautiful, I love you and bless you!!!! "

I may confuse facts from time to time, but I never lie intentionally.
3 is a great cosmic number: 1 + 2= 3
art,

I agree 100% but I didn’t bring it here, Ric did, so here was the only place to defend myself

The EVS1200 was my thread. I would have kept it for the very point you make, but Ric asked me to take it down. Even though I nitpicked a few things, throughout my thread, I made it clear that I was and still am a huge fan of this amp; much more-so after removing the top and the 2 Kubes. Certainly, he shouldn’t have been unhappy with all the pub my thread brought him

I suspect his request had more to do with him no longer wanting to field inquiries due to his apparent rapidly declining health and that he would no longer be making the amp, or apparently anything else.
From what I have discerned the Voyager is made in USA
There are a lot of USA made Class D and GaN options, although many of the components are likely Asian sourced (Taiwan, Korea, Japan) not everything is made in China. A big part of the problem is our own government who literally chased large manufacturing offshore due to noncompetitive tax rates (not addressed by any of the previous 10 presidents= ~ 80 years!), high labor costs, and ever higher Legacy costs


Still waiting on my USA made Voyager GaN amp to compare to my Ric Schultz EVS 1200. From what Im reading the GaNs currently being recommended sound warm, lacking leading edge speed. That’s a big NO BUENO for me
Are you suggesting all the reviews are accurate or that they actually know how to review, or that they all have pristine rooms, proper room treatment, quality  power conditioning, cables, interconnects (I used to slam the Editors for providing true balanced kit to reviewers who did not have true balanced systems and read reviewers saying said so in their review that could not hear any difference. Well DUH 


Ive bought far to much equipment over the decades based on the reviews that my first hand experience found disappointing. That is one of the reasons why I took a leap of faith that you knew what you were doing


I remember back when I was waiting and waiting and waiting for my amp how  often I saw you posting on the boards, and now, when presumably you are no longer making anything that you are still spending time here, sturring shit up. Had you spent more of your time building amps (within a reasonable time frame), you might have sold a lot more and had a lot less time to spread your new age crap



C, where is that thread? I do not see a matching title?
 Fluoride in our (US) toothpaste is nasty, too. Feds have no problem feeding the health benefit bs line to us. Lol

Yes, but it is peddled as a benefit, whereas power consumption cannot be disputed
:((((

I should never have checked out this thread.

Reading Merrills' amp reviews/comments I am so disheartened that the commenters own amps (including Merrill's pre Element series) significantly more expensive than anything I can dream about being so much better. Even the AGD Vivacies (which also have outstanding reviews) are way out of reach 
I contacted Paul McGowan (PS Audio) about his Sellar dac/pre, and also asked whether they are playing with GaN. He said they haven't looked into it, yet. Hmmmm?  They would be the likely lowest price option
G and yet, YOU brought it back up hahahahahahahahaha
OP, why not start a new thread address AGDs concerns? 
celander, please provide a link to new topic
George, wasn't it you who told me when I had the Hattor XLR passive pre that it was a impedance mismatch with both my Emerald Physics, then later with my Audio Alchemy DPA-1?
Perhaps good news for GaN prices. I stumbled across this YT video from CES regarding GaN amp from CREE of all companies. 

https://www.youtube.com/watch?v=gYHY_XKv5tY
The new Nord price is pounds, not USD

from what I've studied such amps benefit greatly from module isolation

Meaning, the expensive chassis is much more than a pretty face 
ric, yes! 

Now that I have my IC and coax and gone back to a WW Series 7 Eclipse PC (MSRP $300) I am truly amazed at the music that was hidden away in my Audio Alchemy stereo amp & dac/pre. So much better even in the bass, that I shut down my 2 SVS Ultra subs. And I finally scored a A PS 5 power supply for the dac/pre, but also got a heck of a deal on PS Audio 700s + stellar gaincell dac/pre. Who will win out? Time will tell
Being a little harsh there George
Ric, Ralph, anybody: can you explain the difference between Ice and Ice Edge modules?
Not saying the VAs aren't good, or better, BUT...

The V A amps aren't XLR, using XLR jumpers on RCA inputs/outputs are a joke, no way to make a fair and honest evaluation

so how can one honestly compare, and did he/she have an agenda 
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
Nice attempt at deflection, but it won't fly here. If you can't answer the question with your personal experience, then you need to stop your incessant 1.5mHz rant
you must have been looking the mirror when you said: the new self proclaimed audio Messiah
Give him hell Ric

You know so much, it's a shame your health is preventing you from building more great products
if you can check out the Emerald Physics room. They should have the new Deep Core PLC plus other cool stuff
Did anyone click on the Singularity 3 High Speed link Ricevs provided?

Ouch $1248 pounds per module. Is it stereo or mono?
Well, we finally know why Gfi is so pro Technics. Seems like a contrary choice of speakers that severely limit amp choices
celander, thanks for the EP room update
klh007
I will be shocked if the Voyager blows away my EVS1200, but then Ric is a proven, and highly capable tweaker


So sad, he will not be able to make more. It would be awesome if he could pass his knowledge on before calling it a day
Ricevs,


so glad to hear this!
George, george, george

Yes, I was forced to pay for the cubes, but they are easily removed, or not even put in place in the first place. And as you the reader will soon see, I have wasted thousands attempting to improve the sound


A lot of what the Kubes do (pos or neg) has to do with the rest of ones system. Case in point...


About 2 weeks ago, as suggested by a fellow 'file, I moved 2 large SVS powered subs (unplugged) completely out of the room; they SUCK for 2 channel (a much more costly mistake than $200 for 2 Kubes).  That alone was a big improvement, and also freed up a lot of space. Because of them my vertical rack was ~ 5ft from the FW. Now I was able to move the rack back to within a foot of the FW, leaving just enough room to plug/unplug cables.

A couple days ago I placed my Emerald Physics KCII speakers (open baffle) on Harbor Freight dollys, which allows me to move them quite easily. They were over 6ft from the front wall to accommodate the subs and rack position.I then dollyed the KCIIs to and fro. They were 6ft from the FW, now being ~ 5ft from the FW, and ~ one foot farther apart, with a bit more toe in. As could be imagined, this was a BIG sonic improvement.


Then I decided to unplug my EVS 1200 from the 20 amp dedicated line and plug it into my Core Power 1800 PLC; another BIG improvement in openness. However, even with top of the EVS off, and Magic Kubes removed, the presentation was still on the soft side.

I had been using a now ~ 10 year old boutique power cord ($800), but decided to replace it with my last Wire World Electra 7 ($240); both the amp and Oppo 105 already had them. Instantly the speed and incisiveness I prefer was here IN SPADES: finally, kick drums now have proper thwack, sounding quite correct, as does the rest of the music. However, on some/many CDs it can be too incisive, but now I can play around with the Kubes to hear what they MIGHT do to improve the sonics on those discs.


Folks, and many of you know this, take George’s damning of class D with a grain of salt. I love my EVS 1200 much more now than when I first got it. And for George to say Ric merely dropped a couple IcePower modules into a box is further evidence of his ignorance, but even crazier is that he suggests that power cords and fuses are "voodoo". ROFLMAO

hth
orchard, you didn't put a space between the end of your sentence and the url, causing it to not function  
I c/pd and got to the www. It’s https://orchardaudio.com/bosc

currently under development. 

looks pretty small for 150 w per mono
Unfortunately, the new GaNs are not yet here to redirect the conversation
I am expecting to beta test a 200/400w GaN soon. It will have to be amazing since my EVS 1200 uses the newest dual IcePower 600 modules, Italian chassis, highly tweaked by Ric Schultz, barely has 80 playing hours and was blowing my mind on very familiar music last night.

It certainly is on a higher level than either my now sold Audio Alchemy DPA-1 ($1999) quite likely the DPA-2 is a big improvement, but to get close to the 1200s power, requires 2 switched to mono ($2999) or the PS Audio M700s ($2999), which sounded vg, but again not in the same league as my EVS 1200 ($2200)
I read golfnutz long winded accusation that I MUST BE in cahoots with Ric. but what I hear him saying is I paid a ton of money for my XYZ amp/s so they must be worth it (Ric keep that in mind, as it makes zero sense attempting to educate these few)


Where what I am saying over and over IS: The EVS 1200 amp is extraordinary value at this price. And I will remind all of you that I am expecting to beta test a GaN soon.


Of course many will still doubt it, BUT, I have no financial loyalty to Ric, but I am driven by a sense of loyalty to my fellow audiophiles who don’t have 5 figures to spend for amplification who still want an outstanding amp
My bad

I missed that he listened to the Evolution One, but looking at their product page, I see no mention of whose class D modules they are using: Ric does.

It’s probably too late for me to remove that part of my comment, but I will try now
OP: Sorry for the intrusion, but Gfi is, well, you know...

Sigh, the Edit timed out
The EVS 1200 (when deep bass is present) might well be a brutish National Football League Offensive Lineman. My EP KCIIs 10" woofers combined with my large room are physically incapable of plumbing those depths, BUT, I certainly have a much more authoritative bass then any of the above class Ds I’ve owned.
From the above moons link: This section seems to blow Gfis MegaHz mantra out of the water. It’s like he was aware of Gfi

Feel the burn George:


I do several things to move the focus on the sound rather than let trolls take over a conversation with things like switching frequencies of 1.5MHz which make no sense.
Gfi
Funny, but that wasn’t my comment. I merely quoted it from the 6 moon review, but Im pretty sure you know that, so...?

I have owned 2 different older generation W4S amps, Emerald Physics 100.2SE monos, Audio Alchemy DPA-1 (UcD), and PS Audio M700 monos prior to the EVS 1200; it’s an entirely different sonic experience.


Srajan set the table: Unlike what Merrill had done for stock UcD/Ncore boards, Purifi’s proof-of-concept demonstrator hadn’t been tuned with silver bullets aka boutique parts, deluxe chassis or even a custom input buffer. It was a cheap stockskate hence handicapped.

the key differentiator on the attack score was that Purifi’s leading edges were enveloped in minor blur or fuzz. The warmer Purifi amp without benefit of costly custom tuning expressed more of a comfort sound. It was perfectly pleasant, attractive and benign but neither was it as compelling nor was it as resolved. Its transmission was lazier hence less effective. How much extra performance could one tap if it was massaged with boutique parts and custom-tuned SMPS?

The EVS 1200 does not have these shortcomings.  When the music calls for it, the EVS 1200 is more ballerina and/or ballet dancer:
Ric is right.




This is GaN amp I am supposed to be getting:
Underwood HiFi
Voyager GAN 200 power amplifier$2500.00

Our new LSA 200 watts/ch power amplifier, Voyager GAN 200, will ship in early November. This is a breakthough product featuring a GAN (Gallium Nitride) FET output stage as found in products selling for many times our $2500.00 price. The current competition sells for $32,000.00, $18500.00 and $15,000.00. Our GAN output stage switches at 500,000 time per second, 5 times the speed of the typical Class D amplifiers currently available. This technology fixes all the issues that Class D amps have historically displayed. AND
Get up to $1000.00 or more in trade for any working amp towards this new technology.
Call us to discuss this superb new amp at 770-667-5633

   

I thought I made it clear, I am only the messenger, but I, at least, have the good fortune of hearing it in my system
shertzy,
I invite you to visit my thread Life with Ric Schultz EVS 1200, a generation or two above NuPrime
Gfi

What? Did you dump on shertzy for mentioning his displeasure with NuPrime Evol Ones? NO

BTW, sherzy, how long did you break them in before coming to your conclusion?
The IT person is not likely to be the copy writer

I just checked now. Looks like changes have been made, BUT, this is still there. Apples and Oranges? 


Our GAN output stage switches at 500,000 time per second, 5 times the speed of the typical Class D amplifiers currently available. This technology fixes all the issues that Class D amps have historically displayed.


https://www.underwoodhifi.com/products/lsa-electronics
Not that NP necessarily slots into this group, BUT, many innovations came about BECAUSE the old guard refused to change from their old ways of doing things


These days we have Crowd Source to help Kickstart those ahead of the curve, but lacking backing
Is it possible that once designers adopt GaN, the sonic differences between that grouping will be to too small to compete?