Class D amps that are superior to all or most?


Recently, I have heard about some Class D amps that may be close to the best there is regardless of class. Certainly, this technology has been in development for decades. The main issue has always been the switching power supply. In this regard, I have taken notice of AGD. They have created a whole new power supply that “switches” at a frequency 100 times the normal silicon based MOSFET. The designer uses a gallium nitride based PS. Interesting, it is enclosed in the KT88 glass envelope that sits on top of his amps. I am aware of two more pricey amps that seem to be also at the top- the Solution and the Merrill. There must be others that compete for the title. After my thread, “Is there a SS amp that can satisfy a SET guy?”, I am still on the quest.
Don’t want to spend $50K!
mglik

IMO, Aavik class D amps (I own the Aavik U-280) are far superior to anything class D I've heard so far. I would have loved to compare it to the new Atmasphere class D amp but since I only have integrated amps, i.e. no preamp, there was no way for me to audition. But I've heard great things about Atmasphere and AGD amps as well. 

 

The finest amplifiers I've experienced, that utilize class-D circuitry, are clearly the Mola Mola. The Genesis of their amplifiers (and other components as well) resides with the engineer who created the UCD module and the N-Core module. Understanding the proper topology when using these modules is key to the overall performance of the amplifier in question. Over the years the engineering team at Mola Mola has continued to refine class-D technology. Consequently, the sonic performance of the Mola Mola products defies the assumed notions of class-D performance. Mola Mola's Kaluga mono block amplifiers started it all and now continues on with the Kula integrated amplifier, and their brand new Perca stereo amplifier. Whether it's about class-D, class-AB, or A, the Mola Mola amplifiers are simply fantastic and represent the very best for the money (and a lot more).  They are transparent, 3-dimensional, detailed, dynamic and oh so musically involving.  Mola Mola is where it's at. 

Post removed 
I said
To those who want to understand, why it’s better to turn off your amps, here it is simply as possible.
(as they like to be drained and recharged otherwise a false permanent "empty floor" happens and your electrolytic power supply caps won’t have the uF storage ability they once had when new
That is not what I was told by an engineer from Cornell Dublier. He told me that to get the longest life the cap should remain charged, and otherwise kept at a low temperature- heat kills electrolytics. If the cap is experiencing high ripple current, this will cause it to heat up a bit- so in such cases it will run longer if shut down and allowed to cool.

In the case of a class D amp, the ripple currents are quite low and the amp tends to operate at a low temperature, so leaving it on all the time is fine insofar as electrolytic capacitor life is concerned.
I stand corrected regarding the Anthem. 😳
Another very good one I heard was Rogue Pharoah. The high end dealer who also sells ARC and mostly tube amps and NEVER sells anything that sounds less than superb said he thought that one was the best sounding he sold regardless of price. Tube pre and Class D amp makes for a dynamic combo if done right.
>> Anthem STR another good one I have heard and recall.  <<
That is class AB, not D.


@mapman What are the best Class D in your opinion?


Well can’t really say having not heard them all. Whenever I listen to my Bel Canto ref amps I think what the h-ll else could I ask for? My BC c5i is very good within limits. My Vanatoo active speakers with biamped Class D in each are golden. Even my little $80 Fosi Class D amp built around a TI chip surprisingly drives kef ls50s very well which not just any amp can do. I’ve heard Veritas and others at shows. All top notch. Anthem STR another good one I have heard and recall. How good seems to come down to power supply and in some cases well executed input circuits especially for use with tube preamps. Looking forward to auditioning some of the latest to come out using GaN transistors, etc.

kuribo
Really.

Really! then look again, and give your      a rest.
"most" being the operative word
Good Class-A IS the most perfect amplification so far
and this again "closest" is the operative word
they are the closest to being the perfect topology so far

Cheers George
I didn't say flawless


Really?

The purest form of amplification if "done right" without any other flaws (except for heat) is Class-A

there is no "flawless" amplification class

I didn't say flawless, I said the "closest" to "being technically perfect", which is still but a dream within a dream.
And amps aren't designed using maths, EE laws and test instruments, and then fine tuned using the same, anyone that doesn't do this, I suggest you stay well away those voodooists and snake oilers.

Cheers George
Go to Dagogo.com and look up Legacy Audio 1.V4.   A good review of the best over all.

That’s your opinion vs technologies opinion.
The purest form of amplification if "done right" without any other flaws (except for heat) is Class-A, be it in opamps, tubes, or any solid state.

LOL, um, no, there is no "flawless" amplification class. Show me a class a amp that can match the purifi spec for spec, watt for watt.
Maybe on paper, George. However it's all about perception. It's all about how different people perceive sound differently. There is no universal best, regardless of schematic or
measurement.

Exactly!


That’s your opinion vs technologies opinion.
The purest form of amplification if "done right" without any other flaws (except for heat) is Class-A, be it in opamps, tubes, or any solid state.
Maybe on paper, George. However it's all about perception. It's all about how different people perceive sound differently. There is no universal best, regardless of schematic or measurement.



Can someone answer this for me please, especially George...
and people with class A amps live with class A defects

The only "defects" good class-A’s have is the heat they produce, this does not effect the sound, otherwise they are the closest to being the perfect topology so far.
Unless you live in central Australia, then the windows would have to be open and you’d hear this
https://youtu.be/4lZt-JLhsg4?t=96
Guess who he’s laughing at?😂

This gives noticeably better sound. No, it will not make it measure any different.

Trusting your ears is beneficial to getting great sound. Tru
Better for you maybe. Just more subjective bs. Like racing stripes on your car makes it go faster, lol. 
Can someone answer this for me please, especially George...

Since all amps have sonic defects and no amp is perfect, why can't people with class D amps just live with those defects inherent to that topology and people with class A amps live with class A defects and people with class A/B amps live with class A/B defects and so on?

Like I said, no amp is perfect. So why all the hate for class D?  My class D amplifier, and others I've had, does a lot of things amazingly well.
Like women, my amplifier has some defects but I'm willing to live with it.

George?...
@mapman What are the best Class D in your opinion? I have a Pascal based D-Sonic M3a 800s that I use for bright headphones (it likes power). It works great but I am interested to know about others.
I will go out on a limb and say Class D amps as a group outshine most of the others as a group. The lesser ones are still good for the cost and the best ones compete with the best.

I say that as an owner running class d amps that range in cost from ~ $80 to $6000 retail and having heard many other amps of all types ranging up to 6 digits retail. 
I well remember the Spectron Musician III and II.
The latter being better.
It was one of the first Class D amps. It also used an analog ps.
A quite large transformer. It sounded great. There were some failure issues though. And the company was a bit shady. My system at the time was miles away from what I now have. So I can’t really give a clear opinion.
The Starke Sound amp looks very interesting. Combining an analog ps should be a significant thing. But since AGD I am just not interested in any other amp. It is easy to say that the search is over!
Kuribo stated:
"You really are clueless if you think all Bruno did with the Purifi design is "tweak" a few parts."

Where did I state this? I already stated (maybe you cannot read?) that tweaking is ANYTHING that improves the sound and performance....including circuit changes. Bruno makes it clear what design changes he has done to take his Purifi module up a tick or so over the NC500/NC1200 (in his opinion....not shared by everyone). One thing he kept using are the Polyprop caps from Wima as his output filter caps......trouble is, Wima has gone back to putting STEEL leads on the caps to save a millionth of a cent on each cap. So all the output filter caps on a Purifi module have steel leads. One of the mods I do to the Purifi module is to remove all 6 caps and dremel off the steel leads and put 6N copper leads on and then test the caps using a signal generator and scope to identify the outside foil. I mark the outside foil and then re-install the caps so the outside foil is oriented to ground. This gives noticeably better sound. No, it will not make it measure any different.

Trusting your ears is beneficial to getting great sound. Trusting the opinion of those that do not listen will just get you bitten (mosquitoes hurt!).
The Starke Sound AD4-320 is priced reasonably at $1300, i almost bought one in Dec. when they were on sale for $1000.

For me the AGD's are SOTA and that's what i'm after.
Hello mglik.  The AGDs are great amps. So is the Starke Sound AD4-320. Four channels, great for electronic crossovers and two way speakers. Priced reasonably. You can return them if you are not pleased. They use a "conventional" (non switching) power supply. 
I should mention that new gear got powered for a full week before listening. Amps got a 24hr 10% power burn-in on a load.

I travelled overseas a lot, sometimes for several weeks. ALL gear off and unplugged. 24 hour toast up upon return, then back to 20 minute warmups
I agree with most of your comments as I also mod, upgrade and build gear and cables.  Passion of mine.  Just look at my virtual system. 
However, one really cannot make a blanket statement about how all gear does not sound any better being left on.  Some do and that has been proved out over time with my ears and a resolving system.  Most gear needs under an hour, but some dacs and amps can take up to 24 hours.  This has been true of my Lyngdorf 2170, TRL SS amplifier and several dacs.  
My EVS 1200 amp is staying on! 
I have a NuPrime ST-10 Class D. It drives the woofers only. I tweaked it a bit by venting the case, adding a tiny fan and removing the balanced input. Before the venting, the amp became a bit nasty once the case hit 40°C. Not no more.

I redesigned my Tubes4HiFi M-125s [mid-range only]. In the PSU, I replaced the underrated [suspect] Nichicon 75µF with a bank of 6  genuine UCC 330µF and a soft start. On the driver, under voltage 400V with 550V.

The first is a mod, the second a correction.

I've been actually 
modding HiFi gear since the 60's. Replacing caps ain't it.

AND there is no SONIC difference between leaving SS equipment on all the time and powering it on and letting it warm for ≈20 minutes EXCEPT THE 'LYTIC CAPS LAST A WHOLE LOT LONGER! And thus the sonics persist.

Other than Class A, SS gear is always sonically vacillating as the thermal operation point changes with the program.
As Ric says,  the caps will still last 15 years or so! No worries. The caps are cheap to replace folks.
And all the while the sound degrades as you boil away the electrolyte.

IMO, as a design engineer, replacing caps is not a mod. While it may alter and in some systems improve the sonics, it is at best transitory.

Electrolytic capacitors begin degrading from the moment they are made. In today's marketplace, the cap you buy today may or may not be identical to the one you bought last year, even if it is from the same manufacturer and the same µF & V.
Ric has taken the Ice boards and amp’s performance to the
next level.
Can you prove that objectively? No. It's your subjective opinion.

we get better sound
No, you get a different sound. Another subjective opinion parading as fact.

Sure people have been modding equipment forever, I never said there was anything wrong with modding. What I take issue with are these claims by these snake oil salesman that they have somehow "improved" the products they hack up. They haven't improved the performance, they have simply changed the sound. "Better sound", "performance up a level", these are all subjective and in the minds of the listener- not everyone who hears their changes would agree the sound is "better". Why is it some people prefer Purifi to tubes and others tubes to Purifi? Peoples subjective tastes differ.

that is what the new model is.....just a tweaked out older jobbie.

You really are clueless if you think all Bruno did with the Purifi design is "tweak" a few parts.




Ricevs,
Have you heard the Legacy D line?  Interested in trying one of the 5 Channel ones for all the 5.1 and 1970's Quad titles I have. Probably about the same price as the lower end AGD model...7K-ish
Try the Sim audio 860a version 2 very warm and natural sounding solid state amp.
Anybody remember Paul Grzybek and his Tube Audio Design line of gear? The one I had was the TAD-60 with EL-34 tubes, bias and feedback adjustment.

He got those from China back when Prima Luna was starting to make a name for itself and dueling with another company who made the same product. This was just as they were becoming established. Paul sold the same units as they did but his were modded.

Paul would buy the units, mod them so you could do the bias without having to open it up, and threw in a feedback knob of his own design so you could tailor it to your own liking.

It was my only venture into tubes but it was great for what it did and there are times when I miss it. Yes, people have been modding for decades.

All the best,
Nonoise
I am really glad the Audion’s are rocking a lot of people. What we need is a cheaper version and alternative lower priced competition. If AGD put all the circuits in one box and got rid of the silly tube thang they could sell a dual mono single chassis amp for half the price. We have GaN amps from LSA now and coming soon GaN amps from Wyred for Sound and Mytek. Let’s see if some of them can compete with the tuberators.....and for less money. Fun time ahead.
Its not that the issue is new.  Even 40 years ago you had people who only believed in numbers.  What is new now is that there is the internet....so people can let their feelings be known.  Some non tweaking believers are on a mission to let everyone know the emperor has no clothes.....trouble is, the emperor likes being naked....ie: most like the results of tweaking.  These non tweaking cult members can be relentless....like a mosquito on a summers night.

Most new models from most manufacturers are just mods of previous models.....they find better caps, wire, resistors, power supply regulators, circuits, jacks, bigger cap banks, larger transformers, better fuses, damped chassis, etc. etc. and that is what the new model is.....just a tweaked out older jobbie. 

When Bruno created the first N-core amp....the NC400...it measured extremely well.  People on DIY audio and other sites started to prostrate in front of Bruno......saying he was the ultimate genius because he made something measure so well......and that it was the "perfect" amplifier.  Well, I took this perfect amp and modded it with better output filter caps and it sounded much better......So, was it perfect before I modded it or after?....I say neither.  Nothing is perfect.  I just made a good amp better. The mod would not change the distortion measurements.  Rarely does anyone mod their NC400 so I no longer make money on this mod.  Here is a link to people talking about the mod: 

https://www.audiocircle.com/index.php?topic=118868.0

No matter what these pesky anti modding/tweaking mosquitoes say.....we all benefit from better parts and execution......we get better sound.....but not necessarily better measurements.  When we come up with measurements that correlate to what we hear it will be very interesting.  So far, we cannot measure anything different in most sonic changes.....but we certainly can hear them.  Long live our ears and our belief in our ability to discern better sound!


Back on track.

I continue to be impressed with my AGD amps, there is a feeling that the music is just right. Music comes to life, singers are real, instruments are real. My musical enjoyment has increased 100% i smile a lot while listening.
Many moons ago when i owned my audio company with their blessing we would mod Bedini amps and sell them with our face plates. I did this with several TT’s, these mods allowed one European manufacture to enter the US market.

So mods have been happening for decades.
I’m really having a hard time wrapping my head around why it is bad to improve the sound quality of a given piece of equipment by modifying it.

We’ve been doing it forever in this hobby (I’ll only go back 40 years ago to the Dynaco 70 as an example) & many have enjoyed the results.

Why the issue now?
Strange post? I could praise a near endless list of folks, but today I decided to pick Ric. Ok. Ric has taken the Ice boards and amp’s performance to the next level. 
Yes it proves this well experienced Aphile likes it. Not sure why you posted that second comment either? This forum is meant for users to post experiences.  Not meant as a launching site for wise guys.

Can't argue with a subjective opinion. It proves one thing only- you like it.

As for being an audio wizard and huge asset, you should save your praise for people like Bruno Putzkeys, who do more than wave their hands and ride on everyone else's coat tails.

The EVS 1200 is simply a stunningly great sounding amplifier. Stunning! Ric, you are an audio wizard and a huge asset to the DIY and audio community in general.  


I have an EVS 1200 amp here that Ric  built with all his well thought out modifications.  I prefer this amp over all the other amps I have had in my system over the last 7 years.  Bested my favorite Clayton Audio, Pure Class Amp,  which is no easy task! 
Nice job Ric! This amp is special and proof positive that Class D done right is going to be the standard very, very quickly. It just is. 
Yes, keep it on 24/7 for best sound.  No doubt.  As Ric says,  the caps will still last 15 years or so! No worries. The caps are cheap to replace folks. These amps are easy to work on when that time comes.  
It’s all about enjoying my music with my system sounding a good as it can.  Best Sonic foot forward. 
The EVS 1200 is simply a stunningly great sounding amplifier. Stunning! Ric, you are an audio wizard and a huge asset to the DIY and audio community in general.  
Thanks for the Love.....you and George must be buddies.....he he.

The fact is that everything makes a sonic difference and no one knows everything......so there are no perfect components. This is why all class A/B amps sound different from one another and same with class D. Every single thing you do makes the sound different. This means that many many people can improve on any one design. Not just snake
oilers...but even flat earthers.


Actually, I don't think much of him either.

Yes, everything makes a difference, the problem is not every difference is audible, nor will everyone perceive your "improvement" to be any sort of improvement at all. Tastes differ, so your operating thesis is flawed on two counts.

Have you any measured proof of actual performance improvements? No. You operate solely in the world of subjective suggestion. OOohhh! These new tar infused caps will take your amp to a whole new level! OOOh! And the sheep follow along.

You are like a parasite that lives off the hard work of others. You don't seem to offer any real products of your own, just mods to other people's work, with the marketing scam that your little tweaks will magically improve on all the heavy lifting done by the real engineers who designed the equipment. Every time some new amp or tech comes to market, there you are, pushing your latest oil on how to "improve" the product.

All you pedal is subjective bs, praying off the insecurity and obsessive, always in search of that magic mod to transform their equipment.

Sad.
"Things need to be kept honest here, if not this forum would have been overrun by fusers threads."

Honestly, what about the subject of this thread?

In response to OP’s question, a number of people here have pointed to GaN technology and specifically the AGD Audion mono blocks. I have these amps now for a few weeks and second the positive sentiment.
My signal chain is Roon (on MacBook Pro) via WiFi (Linksys Mesh) to OPPO 205 to (XLR analog) DSPeaker X4 to AGD Audion to Viking Acoustics Berlin MkII. X4 crosses to 15” sealed Rythmik sub below 50Hz.

The amps sound wonderful. Endless detail, texture, spatial detail even at very low volume. No listening fatigue. Relative to my (obviously limited, but meaningful over the years) experience, these amps are a discrete innovation worth listening to.
How georgie jumped from what constitutes muting to fusers is beyond human ken. No logic. No reason. Just name calling for the sake of it.

And to top it all off, his appeals to a phantom mod system that watches and waits to what he reports back to them is the stuff of fantasy or a very poor attempt to scare people off of enjoying themselves and relating their experiences. 

All the best,
Nonoise

Just your opinion.

NO!!!!

Like I said.
Hey all I asked was give us something, anything at all, to back this statement up of yours below, that’s all, nothing more nothing less.
ricevs
You can see the insides of the Voyager on Underwood’s site. You will want it modified. Lots to do there.