Atma-Sphere Class D… Amazing

@kuribo Make an effort! Between Ralph’s refutation of ricevs’s pointless proposed modifications, and the Cook’s Tour of the inside of the amp that he gives in the San Francisco video (posted somewhere above), there’s plenty of technical information out there. If you can’t accept that they sound good without seeing a suite of measurements, then you’re in the wrong forum--try ASR for size.

~ a happy AGD owner (OMG! also no measurements).

@kuribo maybe crush was harsh. All you have done here is put Ralph’s design down. Praising Orchard and belittling every other amplifier design hardly makes you objective in you admirations. Not shallow just facts from these pages.

As ghasley said start a thread or go for a walk. I am doing the latter I have a lunch date. 

I will be giving Bruno's Ncore stuff a shot next week. Have a Pharaoh II waiting for me when i get home on Sunday. 

See how it fares against my other gear. Has a tube pre and hope it has some soul as such.

@kuribo 

Start a thread or comment on Atmasphere. 

@juanmanuelfangioii 

The fact is I have praised other class d amps as well designed- Orchard for one. I respect and admire good engineering and state of the art results regardless of the name attached. Your efforts to characterize my admiration as some sort of personality worship are immature and show you to be a shallow person not worthy of consideration.

 

@kuribo has a crush on Bruno and any other designer, engineer is an abomination in his eyes. The only time he posts is when people are praising a product that is not  made by his boy Bruno. Then his energy is spent slamming it when he knows nothing of it.

Ralph stays above the fray and continues to sell his products and gains a larger following in spite of Kuribo.

I have personally owned Purify equipped Integrated and it was very bland, soulless,  uninspiring. Guess that is why there is so many of these units for sale here and at USAM. 
 

Kuribo you are entitled to your opinions and I chose to use a spec sheet as only one leg of the decision process, the most important being how a piece will sound in my system paired with the equipment I already own. Often the spec sheet looses.

This is more often than not, an emotional process and the music has to touch your soul. Data be dammed. 

@pstores

Sure, I could look up the patent, or the designer could explain it himself and provide his take on what problem it was designed to solve and why.

With all due respect, while your experience with a wide variety of amps is impressive on its face, all it really means to me is that you have tried a wide variety of amps. I can perhaps assume you are confident in your choice based on that wide audition experience. Your preferences and experiences can not be extrapolated to predict my own, as such, they are useless to me and others in that regard.

I have read and watched the interviews and understand the why- I am more interested in the how. There are many traditional tube amp companies who have seen the future and are now marketing class d amps. Not hard to understand the why.

@kuribo 

  Watch some of Ralph’s interviews and he pretty much lays it out why the new adventure. 

@kuribo 

    You can look up the patent pretty easily. And I would say from a consumer that has had most of those amps in my own system. They quality of the Sonic Characters (soundstage, details, realism, engaging, not bright or harsh, transparency etc) puts them above all others I’ve had in my system. If you read up some posts you’ll see the class d as well as others I’ve owned or had in my system for demo. I have not found any Class D that I liked till these came along. JMHO…

I really don’t care what others think of the sound of these amps, regardless of how many owners praise them- there are probably billions of people who love ketchup and yet I am not a fan.

I would like to learn more about the engineering and design of these amps. It has been said that there was a patent awarded for some aspect of the design- I would like to know more about exactly what was patented. I would like to see the measurements and wonder why they haven’t been published yet when this product has been years in the making- it takes very little time to upload a few files. I would like to hear the designer’s take on how his class d design differs from those of Hypex and Purifi and at 3 to 4 times the price, what they offer over the Hypex and Purifi products that makes them worth the considerable difference. I would like to know why he decided to design his own class d modules, especially in light of the fact that it is no trivial matter and a completely different task than designing a tube amp....I would like to know why the designer choose GaNfets over standard fets and what advantages he believes they offer at his operating frequency over standard fets....

@ghasley 

The problem with those who are certain they know the “secret” to something is the fact that they just can’t stand keeping it to themselves.

+1

Beautifully put.

Charles

@pstores 

Indeed. Its your thread and for someone to question Ralph’s engineering and design chops from left field is questionable. Glad you started it and I’ve never seen anyone question Ralph’s design choices. Atmasphere may or may not be someone’s preference but it absolutely exceptionally well made and designed. Best.

@ghasley 

+10 hopefully we can get back to the amps and not BS….  Opinions are just that. Opinions. And everything in Audio is subjective. But when so many that have heard the amps actually…. Have nothing bad to say about them. I have only heard great things from other owners. And people that have heard them at other venues. 

Can we please move the measurement vs perception distraction to another thread so we can focus on Atma-Sphere's new amp here.

Can you please explain how exactly there can be any meaningful discussion of the new amp here regarding it's performance when we have nothing but subjective opinions expressed? There are no measurements at present available from Ralph to have any rationale discussion of the amps performance. Subjective impressions are not facts, are not able to be compared, contrasted, debated, or relied upon. There is nothing to be learned from second hand opinions, why waste the time?

@tinear123 

  You are going to love them I’ll bet. Guessing since they are a demo pair they have a lot of hours on them. Thats good. I did find mine got slightly better after a few hours of run time. But they were great out of the box. What does your system consistent of? I’ll be looking forward to your comments. I’ll be posting more information also later today after putting them into different systems at an Audio Shop in Minneapolis. And a friends house on my way home. 

Its tough to debate with the self-righteous for they are sure they are absolutely right…and I am sure there are no absolutes in addition to the FACT that what they believe they are RIGHT about is off topic to the OP’s thread. But maybe it’s wrong of me to point this out when he is so lovingly offering up complimentary salvation?

The problem with those who are certain they know the “secret” to something is the fact that they just can’t stand keeping it to themselves.

Can we please move the measurement vs perception distraction to another thread so we can focus on Atma-Sphere's new amp here.  FYI, I am picking up a demo pair in a couple hours. 

@snapsc

Pudelpointers are a very old and rare breed. Once people realized I used the dried excrement and Birch Bark with special Teflon twisted pair wire ties that should definitely increase the value and sonic character of the amplifiers. Hopefully we can try it with the Pass XA60.8’s also. Just think of the overall improvement these amplifiers will see. The Dried Dog Excrement should isolate the Power Supply from vibration better then wood by far. And take all Jitter out of the signal path. I may even try to silicone all the boards on top of a few pieces also. Since the amps don’t heat up I don’t believe smell will be an issue. But the XA60.8’s heat up some. Ummm, we will see how it all works out.

@pstores

I am staying clear of the insults, anti subjectivism aspects. My only point and interest is the comparison between two quite different approaches to class D design. Ralph’s new amplifiers are receiving much positive comments and I believe deservingly warranted.

His high feedback Op-amps amplifier versus a near polar /opposite approach is something that I find compelling with regard to respective sonic presentation. All that concerns me with audio products is how do they sound? That’s why we buy them.

Charles

Three comments here:

1. Once you modify stuff, the value usually goes down.

2. Ralph’s stuff on the resale market sells pretty quickly

3. Ralph’s stuff on the resale market holds its value

Even if wood or glue or other things would improve the sound, why would you take the chance?

Having heard Ralph's amps at the Florida Audio Expo, I wouldn't touch them...well, except to plug them in, turn them on and enjoy!

@pstores 

No doubt that will take it to 11!

@kuribo 

   This is true. I will unbolt the Tansformer and place some Dried Dog stuff in between then wire tie it down. Don’t have much for wood. Although I can put some birch bark top and bottom of the Dog Stuff. I’ll report back.I do have some Class A Wire Nuts also. I’ll hard wire everything. Got new soldering gun from HD last week I’ll try to convince my friend to do it to his Pass XA60.8’s later today also. Not sure how that will go with him though. 

I’ll put money on that he can’t make an Atma-Sphere amp sound better

There is no "better", only different, when it comes to subjective value judgments. No doubt the tweak guru could place Ralph's GaN amp on a pile of horse manure and someone would say it sounds "better" sitting on horse manure than it does sitting on cow manure. But that "better" is only true for that listener and has no meaning to others. Opinions based on subjective perceptions are not facts! Your opinion about how amps sound is no more valid than the tweak guru's opinion to others- they all are meaningless outside a population of one. Of course, you aren't trying to profit off of your opinions and aren't claiming to possess "universal" knowledge...

@ricevs "You need a source that has some kind of digital volume control at 32 bits or more so you won’t mess up the sound."

Would Roon quality? Can you give us some examples. Thanks.

Concentrating just on GaN amps, the observations made for Atmosphere GaN monos may well be applied to a number of other GaN amps. I honestly can see no proof of superiority except that I read a number of subjective expressions. I readily believe that Atmosphere d amps sound wonderful, and would really like to know more on how much better are they than the other GaN amps. This thread, so far, didn’t help me in this. Too many subjective points of view.

How do you define "superiority"? Of course all you have read here are subjective opinions because the vast majority of people here either believe their opinion actually has relevance to those besides themselves or they believe the opinions of others have relevance to themselves. As I have said repeatedly, the only possible way to actually compare amplifiers in a way that can be logically and rationally valid is by looking at the specs. The specs won't tell you if you will like the sound, but they do provide useful data about the performance, design, and can give hints about the sound. As such, they are a good starting point. Any discussion outside of the measured performance is simply subjective opinion and a waste of one's time when it comes to how you will feel about the sound.

The only way to make any judgments of how you will judge the sound of an amp (or any other audio component) in your system, in your room, is to experience it first hand. The opinions of others, regardless of their experience, are not guaranteed to be yours no matter how hard they try to convince you that they "know" some mystical "truth" because they have been "listening to wire" for 40 years.

I have had the GAN 400 and Nova 500 within my system. As well as others I don’t recal the model numbers. I believe they are low feedback not zero. Just remember this advice is coming from someone who believes Nelson Pass, Dave Hafler, Ralph Karsten, Frank Van Alstine, Keith Johnson, Bob Carver, Dieter Burmester, John Curl, David Berning, Saul Marantz and others should be siliconing and wire tying their amps together. And none really have a clue how to make a great amp. And all could learn a lot from him. So you should take what he says with a grain of salt. On top of that… He’s never had a product brought to market. If he had and had implemented his design features of Wood, Silicone and wire ties to hold his amps together. He’d be a world class Audio Engineer. Or at the very least making millions  updating and modifying Pass Labs XA250.8’s. As they aren’t glued together and held together with wire ties. And the people that can afford a cobbled together subpar Pass XA250.8 would be on waiting lists for him to tweak their amps. For me I’ll stick with Nelson, Saul, Ralph for professionally designed and built equipment. I’ll put money on that he can’t make an Atma-Sphere amp sound better. He should buy a set. Tweak them. And Ill bring mine for and AB test to his house, apartment, or trailer park that he lives in. I’d like to see him put his money where his mouth is. 

Real KNOWLEDGE in audio.......is how something sounds

How something "sounds" is subjective, an opinion, not a fact, and thus not "real knowledge", which is something that has meaning beyond one's self.

You can't seem to get beyond the simple truth that your experienced subjective reality and beliefs are nothing but opinions and are no more valid than anyone else's. The guru complex.

@pstores

I do not doubt for a moment your immense satisfaction with the Atma-Sphere amplifiers. Admittedly I have no idea what Ric has or hasn’t actually heard. I’m just intrigued by this very latest no feedback class D amplifier without the ubiquitous Op-amps usage. Did you hear this specific zero feedback design?

Thanks,

Charles

@charles1dad

Well I have had the peachtrees in my system. They are at best mediocre. They don’t compare to the Atma-Sphere. The have a clinical, dry lifeless sonic character. Soundstage and depth isn’t there either. And the don’t have the sort of realism the Atma-Sphere has. The Atma-Sphere is true to instruments. A piano sound as a piano should. As well as Sax, drum beats, brushes and cymbals. I have also had some of the other amps he lists in my system. As to date the Atma-Sphere Class D beats them all. And not by a small margin. And is the only Class D I have like within my system. And I really like them. Recivs is just trolling here and trying to derail the thread. And I doubt he has heard any of the Amps he lists. And I know he’s never heard the Atma-Sphere. So not sure how one can review an amp that they’ve never heard before.

Here is a real sleeper....and maybe a super amp?:

Peachtree has just released a The Gan 1 class D amp that has NO FEEDBACK....no op amps......it is pure digital. Takes PCM via coax only and converts it to PWM in software and uses GAN output stage. NO feedback.

• @ricevs
• Thanks for sharing this.
• Now this would be a fascinating contrast comparison with the Atma-Sphere amplifiers. Vastly different design and execution entirely.
  
  No feedback vs high feedback.
• No Op-amp vs Op-amp implementation. My oh my, quite a compelling listening experience this could be.
•  
• I wasn’t aware that class D amplification was doable without the utilization of negative feedback
• Charles

All GaN amps will sound completly different from every other GaN amp and also all Class D amps using mosfets......the GaN transistor may be one thing that improves sound but it is just one of an infinite number things that change the sound.

Here is a list of my candidates for excellent class D amps at lower prices (under $10K)

1. The VTV Purifi Eval amp.....around $1200

2. Orchard mono blocks (GaN amps) $1500

3. VTV Purifi stereo amp using the New Purifi ET704 modules and discrete input stages using the better Sparko labs op amps, Sparko labs discrete regulators and WBT negtgen jacks.....$2100

4. Dual mono stereo version of above. $2260 or mono blocks $2600

5. Orchard Audio Starkrimson Stereo Ultra (GaN based).....starting at $2500 for basic stereo....options for dual mono and extra capacitance....

6. Peachtree GaN 400 and LSA Voyager amps (GaN based)....basically the same amp with the same modules and power supply $3K or less

7. The Atmasphere GaN mono block $5400 the pair

8. AGD mono block Audion GaN based amps.....$7500 the pair.

9. Hopefully soon to be released.... the Mytek Manhattan amp....stereo amp using GaNs.....something like $7K.

These need to be all compared with each other.....Who is volunteering?

Here is a real sleeper....and maybe a super amp?:

Peachtree has just released a The Gan 1 class D amp that has NO FEEDBACK....no op amps......it is pure digital. Takes PCM via coax only and converts it to PWM in software and uses GAN output stage. NO feedback. This will not have a low of impedance as some of the above and also the distortion figures will be worse than above (Kuribo will freak out at this). However, the sound is said to be really great. You need a source that has some kind of digital volume control at 32 bits or more so you won’t mess up the sound. This thing requires no DAC, no preamp....no cables between DAC and Preamp and amp.....This is exactly what the Technics amps do and also the Lyndorf amps do. There is only a few delivered so comparisons to any serious DAC/Preamp/amp combos have not been made.....but I always like a short signal path.....let’s see what this $2000 amp that needs no DAC or Preamp can do.

Are there clear evidences of the superiority of one GaN amp over other GaN amps?

Concentrating just on GaN amps,  the observations made for Atmosphere GaN monos may well be applied to a number of other GaN amps. I honestly can see no proof of superiority except that I read a number of  subjective expressions. I readily believe that Atmosphere d amps sound wonderful, and would really like to know more on how much better are they than the other GaN amps. This thread, so far, didn't help me in this. Too many subjective points of view. I think it is not timely comparisons with tube stuff, SS can hardly give you the same lightness, 3 dimensionality and body. These are just two different concepts, you may like one more or the other. I like tube gear more but also enjoy in some degree class d, which i trust gives the best in SS.

@pstores , did you really made an ab comparison of Atmosphere class d with the Peachtree or Voyager, or some other GaN amp?

Real KNOWLEDGE in audio.......is how something sounds......there is no common Knowledge of sound.....because there are so many variables......believe it or not.  There is lots of technical knowledge.....but that does not necessarily correlate to sound quality....

there is NO common knowledge

Wrong, there is a lot of common knowledge. There is no common opinion on what sounds "best" thus a market full of products of different designs, classes, power supplies etc. It's not a lack of knowledge but a wealth of knowledge that allows manufacturers to produce products that appeal to a broad market full of consumers with widely varying tastes.

Why is the power supply not a switch mode? I see a large selection of supposedly well designed, medical grade SMPS, by Traco or Meanwell. Yet, I see class A or class D amps not using these. Why?

Most class d amp makers do use smps. There are a handful that use an old school traditional tranny, bridge, etc. If your amp module design is well done with a high PSRR, it makes little difference, according to experts like Bruno Putzeys, who uses smps exclusively with ncore and purifi. They have many good points but some still believe an amp isn't any good if it doesn't weigh 50 kg.

Most class D amps use switching supplies.....some don’t. There are advantages to both. Switching supplies are smaller, cheaper, more effecient and operate at high frequency so there is no 60hz ripple.. But because they switch at higher frequencies they have more high frequency noise that needs to be filtered. As with everything.....it is in the details. If you use the very best parts and execution on both.....which will sound better? Very few know this.....again each manufacturer will usually have their own predilections and go from there. There are many who have changed a switching supply to a linear supply and have gotten better sound. Then there are those who have done the opposite.....and there are those who have tweaked their switching supply so it sounds way, way, way better than stock. As with what I said above.....there is NO common knowledge. Great amps have been made using both. The latest class D from Aavik that Jonathan Scull just raved about uses a modded Pascal module and switching power supplies and all kinds of tweaks. Lots of ways up the mountain of sound.

Getting back to the specific Atmasphere amp being discussed. I am not an Audio Engineer so please excuse the possibly foolish question. Why is the power supply not a switch mode? I see a large selection of supposedly well designed, medical grade SMPS, by Traco or Meanwell. Yet, I see class A or class D amps not using these. Why?

Ego fighting is not making your stereo better or making anyone else's stereo better or making people feel better......or be more happy. What makes you happy? When you are happy you radiate happiness.....and you also want others to be happy. Do you want me to be happy? If so, then praise and raise me to heaven. I am doing that for all of you right now. You are all beautiful.....you are the light of lights.....may you feel loved by the universe.....right now.....for you are.... Every single thing and being in all the known and unknown universe is loving you right this moment. You have never been unloved. Rejoice....celebrate this incredible miraculous moment.....for this very moment is all we have. You are worthy.....you are deserving.....you are incredible!

Share your beauty.....share you knowledge (what you have experienced), share your love....share your magnificience..

There is "what I want" on track......and there is the track of the soul......there is plenty of time to know about an amp......but to live right now in your heart.....well that is precious.......and worthy of eternity.

@ricevs Why don’t you start your own thread and take all of your posts on this one and move them there. Others are here to learn about the Atmasphere Class D amps as designed by Ralph , how they sound , and how they compare to other amps.

Also, if everyone else stops engaging with the non-relevant posts maybe the thread can get back on track.

@ricevs

What kind of op-amps did Atmasphere specify and in what position? What are your recommendations for upgraded op-amps? in what position and why? What will the positive effect be?

Please, please tell us because Ralph’s livlihood depnds on it and the survival of Atmasphere as a company rests in the balance.

Here is what is true with high end audio.....practically no one knows very much.....because it is infinite. Not so with hot rodding. All quarter mile top fuelers look the same and perform the same....because the game is so very simple.....it is horsepower, weight, drag, traction and gearing......and the driver.....that is all that there is........and you can measure it by the clock. In high end audio every single thing makes a sonic difference (my experience with over 45 years of listening tests) and there is soooooooooooooooo much to know that all manufacturers have just a tiny piece of the pie of info. It takes months to just figure out the best wire to use.....this is why every single product at every single price point sounds different. THERE IS NO REFERENCE in high end audio.......no clock to test us.....no race course.....it is every manufacturer on his own....every customer on his own......so there is no common knowledge.....However, as things get tested more and more and TALKED about more and more then some TRUTH will prevail. For those that have never listened to wires, and jacks and whatever then what I say sounds like a different language and how dare I second guess the designers (for they know everything!). Sorry to break you bubble.....but we are all so ingorant.....including me. The more you know....the more you know nothing. However, I have an expertise in tweaking....just like Nelson Pass has an expertise in circuit design.....we all are learning and growing. The more we talk about our experience (what we have listened to) then the more REAL KNOWLEDGE we will have. So, if you do not know anything about tweaking then you have no idea if what I say works or does not work.....and how universal it is. So, who is going to change the fuses out and remove the steel plates and bolts on the transformers and LISTEN and give us some REAL KNOWLEDGE?.......Are we going to just say what we "think" is true or do we really want to improve our stereo. You cannot improve your stereo by fighting tweakers....or fighting anyone......Please, try something new.....figure out what is really true for YOURSELF......do not believe me or Kuribo or Ralph.....find out what is true for YOU.......You can change....you can embrace something new. I encourage you to explore.....Exploration is fun.....being right is old stuff and not fun. Do you want to have fun? Do you want to make your stereo better? Just do it!

Blessings and Love.

Looking forward to reading your impressions. Hopefully, your thread can get back on track and avoid any further unnecessary diatribe.

Tomorrow morning I am going have some fun. Am going to bring these amps and put them into some high end systems at a local Audio Shop in a Minneapolis suburb. Like to hear them drive some really hard loads. And see how they do against some amps 5 times plus the cost. And I want to hear them on big Magnepan and Wilson’s. Just curious…  Should be pretty interesting. Afternoon will have a shootout against Pass Labs XA60.8 amps which I really love. They are 2nd to my MA-1’s in my system. Should be fun to hear if the Atma-Sphere Class D can best them. 
  

So your "mods", to the extent they make any difference, only improve the sound *relative to your opinion* - nothing remotely universal about it - because every mod you do moves the sound away from the intent of the designer. You are setting yourself up as the universal arbiter of differences in *preference*, while also impugning the competence of every product designer out there. Good luck getting anyone to buy into that.

Bravo!

The trick here is understanding that the measurements, if the correct ones are actually made, affect what you hear in a very direct way.

Measurements are what they are-data-they don’t affect what anyone "hears" as they are read, not listened to, unless you are referring to biases induced from the reading of measurements. Testing has indicated correlations between certain distortion spectra and "averaged" or group perceptions but there has been no perfect correlation established between measurements and human response on an individual basis because at the end of the day, you just can’t account for taste.

My goal is to inform people so they can improve their stereo or their lives....that is what I do. The mods I suggested are completely universal. If you did this to a $400 Topping or a $120,000 Gryphon amp the results would be the same....except you would hear more difference with the more transparent piece of gear.

OK, quick logic check here; If "everything has a sound" (nonsense IMO, but...) then the "mods" you suggest will *alter* (key word here, not Improve)  the sound of any of these amps. Again, doubtful IMO, but let's say you're correct. I know nothing about Atma-Sphere or his products, but from reading what he's written here, he clearly designs his amplifiers to *sound* right/good/pick an adjective to him, and hopefully, by extension to his customers. Nelson Pass is famous for designing amps with specific, and different, sound characteristics, i.e. not "flat" or "straight wire with gain". Again, he designs his amplifiers to *sound* as he intends them to, as does Atma-Sphere. So your "mods", to the extent they make any difference, only improve the sound *relative to your opinion* - nothing remotely universal about it - because every mod you do moves the sound away from the intent of the designer. You are setting yourself up as the universal arbiter of differences in *preference*, while also impugning the competence of every product designer out there. Good luck getting anyone to buy into that.

And for anyone dropping $120K on an amplifier that they don't think sounds right, or has a sonic signature that needs "fixed", well, I'd say meds are more in order than tweaks.

I understand that measurements can affect sound.....However, it is just one tool and a very flawed one. You cannot measure resistors, inductors, wire, solder, op amps, connecotrs, damping, shielding, directionality of fuses, fuses, circuit board material, resonances, etc. in any meaningful way......You have to listen.

if you are using a big inductive resistor and then went to a small non inductive resistor....you might measure something. However, all nichrome surface mount one sixteenth watt reistor brands ALL sound different from each other. They are all made from practically the same material....are the same size, etc.....Why wuold this be? Who cares?!.....I A/Bed four different brands and one brand was clearly more transparent then the others......still using this resistor today.....but I parallel them for better sound and use a larger version as that sounds better too........so many things affect the sound that cannot be measured......this is HOW it is.

You have no idea what you are talking about since you have never listened to wires, fuses, etc

No, it is you making assumptions about what I have and haven't listened to- you are the one with no idea.

Wires, etc., do not have a "sound"- there are inanimate objects that pass electric current. The sound is all in your head.

 

The trick here is understanding that the measurements, if the correct ones are actually made, affect what you hear in a very direct way. There used to be a disconnect in this regard because we simply didn't have the technology to show things like the distortion spectra with any detail. But that's been around for a while and if you understand how the ear/brain system perceives sound you can predict what an amp will sound like by looking at the measurements. Most audiophiles are old enough in this market to remember when that wasn't true. But you're not going to get anywhere if you live in the past 😉