Atma-Sphere Class D… Amazing

charles1dad

I don’t believe that people find objective criteria too much to accept. Rather it is inadequate in determining the sonic performance of a given audio product.

Exactly.

it must be based on objective criteria. Seems this simple logical truth is just too much for some

Okay, if that’s your position, that’s fine. I don’t believe that people find objective criteria too much to accept. Rather it is inadequate in determining the sonic performance of a given audio product. Anyway, thanks and I appreciate you sharing your perspective on this forum.

Charles

kuribo

I am not "critical and dismissive of actually listening and judging" ...

That statement is inconsistent with this:

Whether or not it "outperforms" other class d amps can only be judged by the specs.

And that’s how logic works. So while you're entitled to your opinions, you can't have it both ways while also claiming logic is on your side.

this simple logical truth is just too much for some to handle.

Tinear123, I can’t wait to heard your impressions. I always love to hear what others think. And post the system you’re listening to them in. 

 Specs in many cases don’t mean best sonic characters. I’ve learned being in this hobby for 45 years that you don’t listen to specs. You listen to the sonic qualities of the amps. I am 57, and have been very fortunate to listen, own and have many different pieces of equipment. Some had great specs but were lifeless and dry to listen to. Adding to major listening fatigue. Not just my opinion but when we pass the pieces around to others they had all agreed. I stopped being a spec jockey many years ago. Listen to the audio gear and let your hearing be the judge. Specs are posted on Ralph’s website. 
 Am having some audio friends over today and night as well. I’ll let you know what they say about them. 
 

The spec argument has been around forever. I’ve seen so many threads on here over the past 15-20 years. It’s actually good entertainment at times. I give all gear a fair shake not dependent on specs. Actually I don’t look at specs anymore until after I’ve listened to the gear. 

I have a pair of these coming next week for evaluation at my home.

Can't wait to pick a pair of these up. Summer is almost over and I've been struggling with the heat from my amps. These will be my next purchase for sure. 

Jerryg123, Marco1, you will not be disappointed in these in the least bit. I’ve got a few hours of hardcore listening time now. But, these  are truly world class as with Ralph’s OTL’s and preamps. I’d say if you like the M-60’s or Pass XA .8 and .5 series you’ll love these. Next weekend I’ll be doing some comparing with other amps. I picked these over buying Pass Labs .8 XA series amps.  I suspect I won’t be disappointed in my decision. I think either the Pass or the Class D I can live with. It’s going to be interesting to hear them side by side,  to see if one or the other is better. I want to listen to them longer. But I can say. The neutrality and realism I am experiencing is something I have never heard with any other amp. The accuracy to be true to the instruments and vocals is down right scary. I find myself walking into my living room expecting to see the band, vocalist or musician playing the specific  instrument. And am hearing details and micro-details  on recordings that I’ve never ever heard before. They also drive easy (105db 8 ohm) and harder loads (84.5-86 db 4 ohm that dip into the 2 ohm slightly) with authority without sacrificing the realism and accuracy and details. They don’t struggle at all driving bigger harder to drive Maggie’s.  The soundstage is huge and deep, with the speakers I’ve tried them on.  Like my MA-1’s The space between instruments and the separation of all instruments on the stage is also incredible,  probably as good as my MA-1’s. I have all NOS Winged C in MA-1’s and did a ton of tube rolling for the 6SN7’s to get them where they are. And have a lifetime supply of tubes since the OTL’s are so easy on them.  Best part these are not dry,  lifeless, class d’s I’ve that I’ve heard from a few other companies of higher end amps. Definitely the best Class D I have ever heard. Possibly the best amp I’ve heard under $10,000. But I’ll reserve that for the next comparisons. Not fair to say till I’ve had them side by side. 

@charles1dad

No, I am not "critical and dismissive of actually listening and judging", what I said was that there is no way to compare these amps to any others in a meaningful way when it is done on a subjective basis. Saying they "outperform" something else has no meaning to others when all it is someone’s subjective opinion. To be a valid statement of fact, it must be based on objective criteria. Seems this simple logical truth is just too much for some to handle.

One can’t argue with opinion, everyone is entitled to one. By all means listen but let's be clear- opinions are not facts. I am simply making that distinction.

@kuribo 

You sound as if your mind is already made up. I don’t understand your logic, you seem critical and dismissive of actually listening and judging what one would hear. Of course it’s a subjective process. How could it not be? You purchase these audio products with the intent of using them to listen to and enjoy music.
 

How would one determine if an audio product is suitable for them if they do not listen to it? What possibly will the amplifier measurements reveal to you that exceeds the actual listening experience? I don’t follow your reasoning.

Charles

Purfi Amps and integrated shave never lasted more than 60 days in my system. 
 

I do like Nucor Class D had the Bel Canto ref 500 in my system and now one of my son at Grad School has them. He still enjoys the heck out of them.

Another spec sheet jockey. 

I am still waiting to see the measurements of this amp. Have they been published yet?

Whether or not it "outperforms" other class d amps can only be judged by the specs. Comments otherwise are purely subjective opinion which have no factual basis.

Personally, I commend the designer for producing his own design. So many just take oem modules and stuff them in a box.

I will say though that I will be greatly surprised if they perform anywhere near the products designed for Hypex and Purifi by Bruno Putzeys who has been designing state of the art class d amps for over 25 years and holds numerous patents.

When one can buy a complete 2 channel Purifi amp for $1000, one also needs to wonder about the cost of these amps in comparison to those made by Hypex and Purifi. I doubt they perform 5 times better and even if they did, the distortion of the Purifi is already below the audible threshold for most people. Why pay 5x the money for something you can’t hear?　Of course they may have a distortion profile that some find enjoyable, but that is a matter of taste, not pure performance.

@pstores you've evaluated these amps exactly the same way they were just described to me by an AS dealer.  "They sound just like the S-60's above the bass"  I'm currently using the MP-3 + S-30 in one of my systems and Pass in another, so you've pretty much nailed it for me now.  Thanks for the review.  Looking forward to cooling things off 😎

Jerryg123, I am running an Atma-Sphere MP-3 with Vcaps and Caddocks. Tubes are Amperex Bugle Boys. 

Ralph has been making amazing amplifiers for a very long time. My next amplifier will be his class D monos. An acquaintance in Kansas has them and they sound great, will be visiting this client next week and look forward to another listening session at he home.

@pstores what preamp are you using?

dDAFoe,  thanks for the comparisons. Specifically to the 30.8. I’ll be comparing them to the 30.8, 60.8 and a couple from the .5 series. So it will be interesting. I do love Pass Amps. And without doing a side by side I’d say your spot on. But can’t wait to do a side by side for the true comparison. Thanks again

 I’d bet that logo was picked,  and identified, to show .001 lower distortion and zero feedback on their OTL Amps. I’d bet since it was such a success with the OTL’s  they continued them onto the the Class D for same reasons…. But if you look closely at the logo…. It’s pretty damn cool design. And it’s been around for along time, decades. First I’ve heard of the logo complaint. 

soix

5,337 posts

09-03-2022 at 08:10pm 

I’m pretty sure they found that logo to sound the best after testing many others.  Everything matters.

@ddafoe Which Pass amp do you have and how does it compare to the GaN amp?

I owned the X250.8 for maybe 5 years and switched to the XA30.8 a couple years ago.

I find Pass to be very smooth, a tad warm, offers zero fatigue, very natural tone, and throws a killer front to back soundstage.  So far I find the Atmasphere GaN monos to have a very similar sound to my XA30.8.

"very smooth, a tad warm, offers zero fatigue and very natural tone", check.

"throws a killer front to back soundstage, ...", is slightly different but just as engaging I think so far at least.
I find the monos offer a maybe slightly less 'meat-on-the bones', but a wider soundstage, good depth but maybe not quite as deep, but offer a blacker background and ultimately allow me to hear in and around the instruments just as much, just in a slightly different way.

When I get more time I plan to swap back to my Pass and compare the higher frequencies.   That is one area where I haven't made a decision yet on how they compare.   I find the Pass amps to offer very nice high frequency detail and refinement, without being bright or forward.   

I can see why tube amp owners or Pass owners would like these.   Personally, judging them based solely on their looks, power rating, or because they are GaN based as some folks have done doesn't really hit the mark in my view.   They definitely sound different and very Pass like compared to most amps I've owned.  Some folks may love them and some not so much, but in my opinion they are not the type of amp you just throw in as just another Class D or GaN offering.   They are definitely worth a listen if the sound characteristics I mentioned above float your boat... 
 

Curiousjim, where are you located? 

Damn!
 For the first time since the seventies I just moved from all separates to an integrated and now these show up. 
Does anyone know of a dealer in the Midwest?

I’m pretty sure they found that logo to sound the best after testing many others.  Everything matters. 

Onhwy61, have you ever heard any equipment made by Atma-Sphere? Are you aware his Preamps are considered one of the best of the best? His Amps are legendary? How many listening sessions have you had with Atma-Sphere gear? 
 

  What I see in this thread for some reason is small number  of Atma-Sphere haters. To me that makes no sense. Especially the way Atma-sphere shares information and in a non bias way. And I’ll bet that none have spent anytime with the gear. Whether it’s OTL or his new Class D. The professional reviews say all great things of his amps. I’ve never seen a mediocre review let alone a bad review. And he doesn’t Advertise or really Market his products. Why? Because they are that good and he doesn’t need to. One of the few. I’d you have a grudge against Ralph whatever…. But not sure how you can bash a product you’ve never heard. That’s actually weird…. 

I don't like the way the logo looks.  It completely and utterly makes the amp a non-starter with me.  If a manufacturer can't design a cool looking logo then what are the chances of them making a great sounding amp?  I swipe left on this one.

So, who is going to be the first to pop the hood and show us the engine.....with close ups?  Show us the meat!  he he.  

I got the Silver Faceplate. They look pretty nice in person. Looks doesn’t add much to the sonic qualities. Maybe give you some placebo effect. Like the McIntosh MC452. Looks nice. But not the best sonic qualities for an amp that expensive. I had one for a very short time before I sold it. I’d rather pay for function.  I guess the same could be said for Pass Labs Amps also. But hell I love the Pass Labs Amps. The First Watts are also damn nice amps. Glad people like Nelson and Ralph build for sonic qualities,  not beauty contests. That could make it that much harder for the common folk, like me,  to get some awesome gear. 

100 watts @ 8ohms per block, utilitarian plain enclosure. Does not seem that impressive.

@avanti1960 Really?  That’s how you pre-judge this amp from one of the most reputable designers in the biz?  Pretty shallow dude.  Have a listen and then see what you think.  I believe after that you’ll be searching for recipes on how to cook crow.  Bon appetite.

Book, meet cover.

The irony !    One of the best mfg of OTL tube gear makes one of the most highly acclaimed Class D amps yet.    Go figure

What's the irony?  Do you even know the meaning of the word irony?

That you say Go figure - you are blessed.

100 watts @ 8ohms per block, utilitarian plain enclosure. Does not seem that impressive.

Thanks Grannyring and Sandstone….  Big jump going from Tubes to Class D. 

Yes, crazy isn’t it…
 

oddiofyl

2,267 posts

09-03-2022 at 08:33am 

The irony !    One of the best mfg of OTL tube gear makes one of the most highly acclaimed Class D amps yet.    Go figure

Ddafoe, yes you are correct they run very cool. I wasn’t that surprised by that. As Class D do run cool. Hence the reason I got them. It was a choice of Pass XA 30.8 or the XA 60.8, or Atma-Sphere Class D for summer listening. The Prototypes I had heard a few years back were pretty good. No way close to as good as these. So the apprehension was there.  I looked for reviews from owners and such. Then thought Ralph’s been a very straight honest person. And I feel he down plays his own gear some. So I took the chance. Besides $5400 for a great amps these days is cheap as hell considering what others cost. I suspect what I am going to find is these amps outperform many other amps costing much much more. Regardless Class D, SS or Tube. I am not looking for a certain type. I am looking for excellence . So if the Pass outperforms the Atma-Sphere Class D, or any other can within in my price range I am willing to spend…… That’s what I’ll end up with. I have a budget of $15,000 with selling my other amps and such. So at the end of the day. The best amp under $15,000 wins. As long as it’s not a room heater. With having a super insulated house that’s a concern. My MA-1’s I’ll keep for winter listening. As they aren’t going anywhere.

I’ll be comparing these amps to Pass XA series including the .8’s. As well as other amps. Will keep all other components the same. And will hold the Db’a the same as well. it’s going to be fun couple months doing some serious comparisons. 
 

    I still have a hard time believing they are this good. The realism is absolutely incredible.  

Condosound, my MA-1’s would be $21,0000 new.

Atma’s are good but overpriced....400 watt Peachtree is 90% there and costs under $3,000

So, you have completed a full costing analysis on all of the necessary inputs (defined very wide) in order to make this comparison?

Others may suggest the exact opposite of what you suggest - that Peachtree is utter junk and something that a person with more dollars than sense would consider buying.

Because 90% there is sufficient?

I say no.

Declare your interests. I have none.

What I do know is that I’d rather pay way more than 5,400 for a 100% "there" than 3,000 for something not quite "there" and possibly has unresolved component or design issues.

Why on earth would anyone settle for less at these price points?  I buy for keeps, not to experiment.

@mbmi Have you heard the Atma-Sphere GaN amp?

@ddafoe Which Pass amp do you have and how does it compare to the GaN amp?

Atma's are good but overpriced....400 watt Peachtree is 90% there and costs under $3,000....I'm hearing details I never heard with my tube and class AB amps that I love. Every piece of music I play sounds "new" with all this added detail...very exciting....but I still love my 845 SET Tubes.

Idle current is so low that it invites leaving them on 24/7 yet if the amps happen to be cold, they need little to no warm-up to sing.

@pstores, congratulations on your purchase!

I've had my pair for ~ 2.5 months now, and leave them on 24/7; it is amazing how cool they run (like barely warm at all, unlike my other amp which is a Class A Pass). I might have 300 hrs of play time on them at most and think they likely have improved some over that time.

I'm feeding them with a Meitner MA3 and Sim 740P, and they are most certainly not out of place. 

And do some comparisons to some other high end Amps Solid State, Tubes and Class D’s, also in other systems I’ll do a more comprehensive review.

I can’t wait for your precise and articulate tribute.

In full knowledge that you may only change one variable between comparisons, all other things being held constant.  This will invariably involve comparing components that are not technically equivalent.

But you know that, having read all of knowledge provided on Ralph's website.

No, not really.  I seek informed analysis from one who is cool, calm and collected and in control of their cognitive facilitates.

@pstores, You're fine.  Nice post on a very interesting piece of gear.

I haven't heard the Atma MA1's but do have 97db speakers and the Atma M-60's are better than my 300b amp in my system. I used the Allnic 300b amp for years before getting the Atma-sphere. The 300b is great, but not as good in my system.

I also have had Bel Canto Ref 1000, and Merril Audio Veritas in my system, Although the Bel Canto was with Joseph Audio speakers. I am not a huge class D fan, although if you change your system to them, you can make it work well.

What convinced me to try them was Ralph saying he uses them in his system. That caught my attention. Then when discussing with Duke Lejeune, he said he was planning on getting them for his system, although he said the bass would be different from the M-60's, not necessarily better, and making the statement that the M-60's were a hard act to follow. That did it.

The differences are baked in. Ralph designed them from the ground (literally) up.

I would be open minded enough to try Ralph's Class D amps.   They would never release an amp that didn't sound great in my opinion.    Why bother?     $5400 is not out of line for.a great pair of amps .  Sure it's a lot of money, but you will spend that much for a really good 300b or more , unless you build it.  

MA-1s/140wpc for $9,800, and Class D/100wpc for $5,400, into Khorns which need only a few watts? Time to be rescued by a less expensive 300B tube amp which sounds very much "like a tube amp"...

The irony !    One of the best mfg of OTL tube gear makes one of the most highly acclaimed Class D amps yet.    Go figure

Nice write up OP and I completely understand your upfront nagging concern of what they will sound like. It comes from your past experiences and that is completely reasonable. I am most interested in these amplifiers and will also have to allow my trust in Ralph to win over some of my up front Class D assumptions.  Ralph is truly one of the very best designers and gentleman in the business.

@ghdprentice   +1 ON HIS BS OF EXPECTING TO HATE THEM

Specs say gain 22db. Am guessing that is input. Could be wrong though.