Time to buy a class D amp?

Looking at your posts, I have noted that made an error in my initial post. 
I wrote: 

" I have no doubts that they (class D amps) posses the maximum ratio performance/sound quality among the amplifiers of all classes", 

whereas I meant that class D amplifiers give the maximum ratio
performance/price, among all classes of amplifiers, where 
performance = sound quality. Or more widely, we may let 
performance = (sound quality - weight - size - energy consumption).
Indeed, i think that Class D amplifiers are unbeatable in this issue and, very unlikely, this can be changed in the future. Hooking up for the first time my $1500 class D amp to my system, i was sincerely surprised how one can get that quality of sound for that money!
At the same time, i think Class D is still under the basic development process (e.g. @yyzsantabarbara has posted a website speaking about recent developments in PURIFI Audio). 

I share (a common?) opinion  that class D amplifiers give a clear transparent sound with details and resolution. True, but something is missing. The fact that sound is transparent does not mean that it is warm and live. Take a frozen or a wax figure. It is clear, transparent, even more bright than a human, but you can see that it is not a human - the spirit is missing. Likewise, Class D gives a detailed, bright  sound, though  some warmness is perhaps missing. 

It is possible that there are class D amps, that i have never auditioned,
sound  non-wax and warm (many of you mention Nord Acoustics  amplifiers). But it turned out that one I have, PS Audio Stellar S300,  an ICEpower model,  should be one of the warmest sounding class D amps (so i am lucky!).  Athough i can still enjoy it, not to the same extent. I share what George says in points 1 and 2. I do not think these are technical issues, rather they come from the auditioning experience. The tweeter damage issue, i think, should not be typical for any class D amp -- perhaps, this particular case was provoked by some wrong current or a defect of fabrication or the amp or/and CD. 

Thanks @golfnutz for your notes on Red Dragon S500 with Thiel CS3.6 that i bear in mind (I also own CS6s, both are excellent speakers, CS6s sound a bit more real though). 

I see Class D, being an ongoing development (carried out by the scientists), as the future of the amplifiers. Already today (unlike electric autos vs gasoline ones), Class D amps are considerably cheaper than Class A, AB amplifiers. They are much  lighter, smaller, do not get hot and consume little energy. With all of this, the sound quality that they give is not that bad at all, and, i think, it will become better in the future. I think this development deserves a 100% support from all of us. 

Cheers, 

Nodari
 

I think Tim gave a very clear and justified response. Both, listening experience and scientific measurements prove that class D amps are the most quiet ones, not only with the highest signal to noise ratio, but also, with the highest ratio performance/price; i.e., take a class D amp and compare it with another amp of any other class with the same price, and you will have much better sound quality in class D amp, and it will be lighter, smaller and will consume much less energy than the other amp.

Other issue is the sound quality of class D amps, in absolute terms, regardless of the price and other parameters. This issue might be discutible but note that in this case you will be comparing a class D amp with an amp that costs much more. Its like  the two amps are not in the same weight category (so it would be unjustified to compete them). In this sense, class D has no completion. 

Thanks @sumaato for sharing your experience with using different pres for PS audio Stellar S300 amp, and thanks @darstar for letting me know about ATI class D amp (yet unknown for me). Did you select an integrated one or otherwise which  preamp are you using? 

As to the use of preamplifiers,  I suggest that if the source signal is good (and it has volume control) then this signal does not need to be altered before it comes to a power amp. In general, why the source signal should be altered in case you have a good DAC?  I suppose that  a good pre should not alter the signal coming from the source. Its like if someone does not like a salted meal. You still give him a salted meal suggesting to add much sugar to it so that to compensate the excess of salt. As a result, you get much salt and much sugar (but you just wanted a meal without salt, that's all). 

Best, 

Nodari

 

Tim, did you audition Cherry amps (Gold Cherry, Megaschino etc) orNuPrime class D amps? Do you suggest that ATI class D amps could be better?  Thanks

Thanks indeed, Tim and @snapsc for your comments! 

I did not know, Tim, that all these brands produce Class D amps.
It would be virtually impossible to verify all of them (but will make a search for some of them) and given that i live in Mexico, buying and returning would not be really feasible. 

Although I am not yet completely convinced that it is already time to buy (another)  class D amp, i am still desperate to try one more because i like class D concept. I listen to 2-channel systems (no home theater!)  and could take an option of a stereo amp or monoblocks. Naturally, i would only consider a candidate with a high coefficient *performance/price* according to my vision of class D concept. 

@snapsc, your impressions on 2-Cherry after trying two other (known for me) class D amps are important for me. I was also inclined to a Cherry amp. The biggest and supposedly best one is Megaschino  (should be very good at $6900 in class D), then comes Gold Cherry with the same price i think and Cherry 2 with a much more accessible price. My question is, which of these three models maximize ratio  *performance/price* ?
Did someone compare these three? 

Hey Tim. An important attractive side of class D amps is their low price 
and high ratio performance/price. I am not sure if for Merrill class D amps this is also true. Neither you nor me have auditioned it, given their price, they should sound almost magical to have a high ratio. Buying   Merrill amp would be similar to buying a very expensive electric car. I have a hybrid one which did not cost much more than similar non-hybrid onces, this made a sense. Demo Cherry amplifiers are on sale, some of them cost nearly the half of their normal price. If their sound quality is somewhat close to  Merrill class D amps (at least, not too far), ratio performance(Cherry)/price(Cherry) >> performance( Merrill)/price( Merrill)
even considering used price. And, perhaps,  older Veritas series amps are not magic sounding (if not, why they have changed the profile of their class D amps?). I am curious to compare SQ of Cherry,  ATI, Veritas and Element amps

Guys, perhaps, "time to buy a class D amp" is closing up... :)

Interesting developments in class D, did not think there are so many (new) brands producing class D amps listed in this thread, e.g.,  the last one, Voyager GAN 200 power amplifier at $2500 looks interesting (I think they could have a better ratio performance/price than Merrill amps). Their serial production is planed to begin this December, as Walter Liederman has notified. 

Tim, I am keen to audition D-Sonic amps (unfortunately, they are not so flexible in sending their stuff to Mexico where I am currently living). I am not sure about Red Dragon as they (S500) seem to be not so  tolerate with low impedance speakers (one below 4 ohms, see an earlier post in this thread), don't know about their new series amps that will be released soon.  Let us keep each other informed. 

Cheers

Nodari

Hey Tim, 

Good intentions, I wish you to come to a correct choice (by the way, 
it would be interesting to try your D-sonic momoblocks
in case you wish to sell them). 

My journey to class D is not yet so extensive, in fact it it remains at an initial step - a light journey to Class D via class A, a non-expensive experiment that i made I have tried to replace PS Audio Gain Cell ($1700) pre/DAC with a Nuprime PHA-9 ($650)
as a pre for PS Audio power Stellar S300, with a quite positive  result. The Nuprime has surpassed my expectations
(also taking into account its price):  instead of a wax clinic sound
now Stellar gives a live open well balanced sound that
is already pleasing for audition - an essential difference for me, from non-pleasing to a pleasing sound. HPA-9 is class A, it gets hot and the hotter it gets the better it sounds - no way, this is how class A works. Supposedly, it is designed to give a tube-like sound, which, i think, is achieved. It turns our that the cosmetics may change the face -- something that i did not expect. Perhaps, some tube pre would even do better, but i am not currently interested in this, as a good value Nuprime has already emerged. I feel now safer and becoming convinced that class D may attain what i wish.

My goal though is to stay in class D -- not yet clear if it is possible. We need to find a class D pre that does the job correctly,  without any cosmetics, and then see if a power class D amp will give a desired result.  

To this end, I soon expect to receive a Cherry MEGAschino class D power amp and a Cherry DAC with a volume control. It is a demo  MEGAschino  (DAC is also demo) unit sold for $3900, $2200 below its retail price. You may wish  to hold on, I will let you know about my impressions on Cherry amp in a near future.

According to what i read,  MEGAschino  is comparable with the best class A amps (@matias do you know how  MEGAschino  compares with your class D Apollon NC800SL?).  I feel it should be close to the reality, i will keep you posted. 

Cheers

Thanks Tim
I do not plan to be close by in near future but will bear your proposal in mind. If you will visit Mexico i would suggest you the same.

As i told you, i will let you know about my impressions on Cherry Megaschino and Cherry DAC with volume control once i will have them. Earlier i have ordered a more moderate Cherry DAC 1 tb which gives a pleasant tube -like sound. I have bough a demo one for about 400$ and it sounds  not much worse than $7000 reymio dap 777 thought it has a single input, as one i have ordered recently. 

I remain curious to audition your d sonic monoblocks. 

I did not understand what kind of patent is this as class D amps are widely used for already more than a decade. 

Meanwhile, I have some class D updates and can share my first (still superficial) impressions on a class D Cherry MEGAschino  amp (a demo stereo version). I got it recently from  Tommy O from DAC (Digital Audio Company) together with a (demo)  DAC SHV 2 with volume control. 

Let me note that MEGAschino  is not a typical representative of class D: it is quite heavy (about 20 kilos), not as small, it does get hot (not extremely hot) and costs a few times more than an average class D amp. So nice characteristics of a class D amp are not present in this amp, which is based on a module  designed by the same company (DAC). At the same time, it gives a detailed, clear non-wax and non-frozen music reproduction. I can even say that the sound quality is more alive and detailed than that of  may class AB amps, a surprise for me. Roughly, it sounds like a good solid state class A amp while gets less hot and is still less heavy. Again, these are my first impressions that might be completed or/and altered later. 

At the same time, i am not impressed with DAC SHV 2 (about $1500 new). It has a single digital input. As a (passive) preamplifier, it was not so efficient with MEGA -- the sound had no dynamics. As a DAC, it is slightly better than PS Audio Gain Cell (slightly more soundstage and definition), but Gain Cell costs the same and is also a real preamplifier (with enough number of digital inputs, several line inputs, coaxial, optical, USB etc). 

Currently I use $650 Nuprime  HPA 9 headphone amp with MEGA as a preamplifier, with very positive results (although HPA 9 is class A). My desire to stay in class D is not (yet) fulfilled. Though  in terms of ratio performance/price  MEGAschino may not beat other class D amps, in absolute terms, it is a very good sounding amplifier. I hope I will stay with it in my main system. 

Could we combine  pretty face with nice legs without chain smoker in class D? 

My speakers (Thiel CS 6) go down to 2.5 ohms at 8 kHz, the output impedance of Megaschino is measured at 10  kHz. I did not note any damping problem though am a bit surprised with the power issue.
Supposedly it gives over 600 watts at 4 ohms, that i do not really perceived  (I feel it gives about half of that, though its power is quite sufficient for my needs). 

George, 

I cannot affirm anything certain on this, but, perhaps, there is a doctor that already can already convince  the girl not to smoke, chain smoker is no more needed. The girl then would shine with her legs and face. 

According to Tommy O from Digital Audio Company, their module design is already fast enough so that there is no further need in GaN-based technology (used, e.g., in  Technics SE R1). I am citing  what  he wrote to me in this regard (please note that i am unable to judge on the technical part/proof for his statements):

citing : 

" I wanted to mention this before…. These GaN based Class-D amps have the same issue as other non-Cherry Class-D in that they are going for bench specs as opposed to sonic excellence. Without getting too into the technical aspects, GaN FETs require use of support chips that don’t support our unique topology, and our design is different in that it’s already super fast (the benefit of GaN is supposed to be speed). We are able to achieve better bench specs than any other Class-D we’ve seen, but we “tune” the modulation and control for best sound, and this costs a few dB here and there -- but sounds better. For example, the MEGA design can reach about 130dB and 0.0004% THD on the bench before tweaking for sonics. This is with non-GaN FETs. After tweaking, the specs are still great (120dB and 0.001% THD), but the smoothness is preserved, and the harsh/analytic sound of other amplifiers is not anything we want coming out of a Cherry Amp!! We are always getting compliments on sound quality, and this is the “proof in the pudding”. "

I wish you all to enjoy the sound that you get from your current audio gear, and further, to be able to improve it according to your needs and taste. Perhaps, there is no absolute audio reproduction that is equally good for all. Besides, sometimes a good or bad quality recording makes much more difference than thousands of dollars spent on the upgrades and "improvement". Everything in this life is relative (as Einstein has taught). On an ideal recording reproduced on an ideal equipment you may get what you want, but it is difficult to have permanently both of them... 

Happy New Year! 

It's not a speaker issue, but it was the gain cell preamp. I bought first Stellar and then after a few months the pre. Before that i used Stellar 300 with a Mcintosh pre. After some hours of break in gain cell sounds better though its not perhaps an ideal pre for Stellar. What pream are you using?

Hpa 9 as preamp with Stellar s 300 with a quite good outcome. Gain cell is not as good but still is getting better with more hours.

I also used Neprime headphone amp

It should have already about 150 hours (almost enogh). It did get better, after all it's not that bad. Dac is not excellent but perhaps aceptable for some settings and pre has i think 8 inputs. It does not get hot (even warm) and consums only 20 watts. I do not peceive a lot of distortion in sound. 

It looks interesting. Hpa 9  has also two levels of gain, i always prefer low gain.
Keep us posted on your impressions on amg pre. 

bolduque , in addition to the useful and valuable notes by Tim and George, i would still suggest you to try a class D amp. You may spent less money for the sound quality you will get, will save space and energy. There are very good sounding class D amps, and i am now convinced that some of them give a very neutral uncolored sound (one example is a Cherry Megaschino amp that i am using already for about a month or so -- i can hardly imagine an amplifier that would have a more neutral  and clean (and perhaps also detailed) sound, the rest is the thing of a taste, and you can "colour" your sound with an appropriate preamplifier depending on your taste). 

Red Dragon, monoblocks, if they are new model (released this year) then $2K  could be a good deal, otherwise not. Bear in mind that Reg Dragon is not good for low impedance speakers (if your speaker are 8  ohms then it would be fine).  

With the same success, you may demo two class ab amps. How many class d amps exist? You cannot judge just based on this experience. You will have more distortion on most class a b amps, can a distortion give you a live sound?

You may not be disappointing. The design is nice. 
Take into account that Class D wattage is not the same, you may have about the same power as with your ATI (tube 50 watts \approx class ab 
100 watts \approx class D 200 watts).