The NAD M33 will cancel your complaints about Class D

Good point, jjss49. Some class D naysayers just parrot comments about class D they heard elsewhere, it doesn’t seem to matter much which century or decade they heard it in, many haven’t even bothered to audition a good quality class D amp and yet they don’t hesitate to dismiss them out of hand.
Comments like the one from cdamiller5 are worthless without supporting details. Why even bother posting?
Hopefully, cdamiller5 will take this post as the semi-constructive feedback that it was intended as.

Tim

seanheis1:
" Here is a quote from Bruno Putzey, creator of Hypex modules and Mola Mola in an interview with Sound & Vision.

S&V: Generally speaking, what are the key benefits of Class D versus the traditional Class AB and Class A designs that have long been favored by audiophiles?

BP: Efficiency and therefore the ability to construct amps that are powerful for their size. Only that. Modern Class D amps, in particular mine—ahem—sound good not because they’re Class D, but in spite of it. I can’t repeat that often enough. Left to its own devices, a switching power stage tries to do just about anything except amplify audio. You choose Class D to save energy but it’s all elbow grease after that. People don’t realize how much more challenging Class D is compared to Class AB. It’s truly an order of magnitude."

Hello seanheis1.

I read that full Sound & Vision Bruno Putzeys interview years ago. I noticed you selectively cited only the above quote from BP from the interview because it, apparently, supported your own opinion on class D but failed to cite other quotes that do not. I believe it’s useful for anyone on this thread or anyone interested in class D in general to read the entire interview, less your selective censorship and cherry picking of quotes, to obtain a better understanding of class D and BP’s unrestricted thoughts on the subject. To promote the honest, full and accurate edification of thread readers and continue this free and open discussion of the pros and cons of class D amplification, here’s a link to the complete Sound & Vision interview:

https://www.soundandvision.com/content/bruno-putzeys-head-class-d-page-2

For those readers lacking the time to read the entire interview, here are a few other interesting and relevant BP quotes from the interview seanheis1 conveniently felt the need to omit:

"S&V: Conventional wisdom says a great amplifier has no sonic character of its own and, beyond boosting the signal level, is transparent in the audio chain. But does the nature of high-quality Class D amplification—perhaps through the absence of distortions found in other circuit topologies—produce a particular sonic signature or specific attributes you could describe?

BP: Well, if the amplifier is truly great that’s absolutely right. Sonic signatures are what you get when you approach the same ideal from different angles. There are a few distortion mechanisms conspicuously missing in Class D, mostly those related to the input stage of a Class A(B) solid-state amplifier and nonlinear capacitances. Those are also missing in valve [tube] amplifiers so it’s quite common for people to notice that a Class D amplifier is somehow reminiscent of valve amplification in terms of “sweetness” for want of a better word.

I’ve heard several reports of valve aficionados ditching their glassware and switching to Ncore. All I can conclude from that is that those people clearly weren’t actively seeking the distortion of valves as many believe, but instead had a legitimate beef with certain sonic aspects common to most solid-state designs. That’s one thing I have to explain again and again to my fellow doubters: when audiophiles report a particular listening experience, that experience is real. Trust that. Just don’t trust the explanation they proffer.

S&V: The new generation of Class D amps are obviously good enough to herald audiophile kudos, as we saw most recently with David Vaughn’s review of ATI’s AT527NC and AT524NC amplifiers, but what lingering issues might still need to be resolved to move performance to an even higher level?

BP: I’d say that basically the cat has been skinned. Further refinements will surely happen but the same can be said of the other amplifier classes. In terms of things affecting sound, I don’t see any fundamental outstanding issues that merit much attention—it’s mostly down to lesser implementation details, ordinary technological progress, and perhaps some more adjustments in the math department. I would like to see magnetic materials with less hysteresis though."

The complete interview contains a lot of other interesting and relevant information about class D, I encourage anyone wanting more unadulterated information on class D to read the full interview.

Tim

+2 jjss49

     You gave a good summary, seem to have a good grasp of the subject and true dat.

Tim

     Ah, fun with FFTs.  Teo_audio's posts can be relied upon to be interesting and very cerebral as he explores the core of subjects from unexpected directions.  Excellent work and please keep 'em coming.
     I've read and participated in numerous dialectics about class D amps ever since these amps began to be very good about a decade ago. It's weird, but just in the way it's something to note, that the reactions to and discussions about class D amps haven't progressed much beyond the apparent conclusion that many, including myself, love them and that many do not for various reasons. 
     l find it confusing and confounding, however, how I can perceive the performance of many of the class D amps I've owned or listened to as being exceptionally good while many others perceive sound quality deficiencies with class D amps, or at least claim they do. 
     My suspicions of these supposed class D sound quality deficiencies, and even the motives of the claimants, stem not only from their complete and consistent lack of any proven scientific supporting evidence but also from my personal complete and consistent failure at perceiving any of these supposed sq deficiencies they've described during the past 6+ years of my owning and using 3 different brands of class D amps and listening to many more.
     There's been a serious dichotomy of opinions on the performance quality of class D amps over the past decade or so.   I've chosen not to be overly concerned about these opposing opinions since I perceive my class D monoblocks as performing spectacularly well in my system and I don't perceive any of the claimed sound quality deficiencies perceived and described by some others, which means by definition that these alleged sonic deficiencies don't even exist according to my perceptual reality.  Perhaps I'm just lucky for not being able to perceive them or perhaps these supposed deficiencies actually don't even exist. 
     Which is it?  I'm not sure but I think it's best that I keep an open mind.  I believe it's possible, if not likely, that future scientific evidence may emerge that identifies and proves that class D sq deficiencies actually do exist but that only a minority of individuals have the ability to perceive them.  There are no guarantees, of course, but it would explain this dichotomy of opinions rather nicely and neatly.
     
     The other subject I've noticed a serious dichotomy of opinions on is the big, fat, orange, dopey guy. This recent and very important election, about the performance quality of our President along with the fate of our nation and democracy, I can't avoid being overly concerned about since I, and about 80 million fellow citizens, perceived him as a collection of the worst human personality traits along with the leading candidate for the worst President in the history of our country. 
     The fact ,that about 70 million of my fellow citizens actually voted for 4 more years of this disaster of a man and Presidency however, also greatly concerns me.  Unfortunately, I can only rationalize this mass attraction to such a poor excuse for a human being by realizing that Trump happens, the attraction likely representing more of a protest or symptom of underlying problems as much as anything else, such as an entire group of hardworking, middle class and patriotic citizens perceiving their relatively inequitable conditions and treatment as well as being politically ignored for far too long.  But that's a worthy discussion probably best had on another forum.
     Anyhoo, I believe the opinions on both class D amps and Trump will remain characteristically contesteous, combative and dichotomous for the foreseeable future.  Only when all future developments, histories and facts about each can be fully known and scrutinized from the clear, accurate, honest and complete perspective of retrospection, which may  require 100 years or more.will the full story be known about each subject.
     
Tim

I detect no bloviating, rambling or commonness about teo_audio
I just sense intelligence and enlightenment to the maximo
If deep thoughts happen to be your bailiwick
Just find one of his posts and give it a click
Sure, if you're a bit dense, his posts may initially go over your head
Considering your disabilities, perhaps they just need to be slowly reread
I consider Deep Thoughts by teo_audio to be a real treat
Wittiness, cleverness and intellectual stimulation that can't be beat.
Please be respectful to my man teo or you'll force me to be bold
Remember naysayers, I can bring you in warm or I can bring you in cold

Thank you,
  Tim
 XOX 

 

     Sorry, I just noticed my link to the complete Sound & Vision Bruno Putzeys interview began on page 2.  Here's the corrected link that begins properly on page 1.

Oops, I apologize,
  Tim
https://www.soundandvision.com/content/bruno-putzeys-head-class-d

kw6: " Unless you only listen to analog master tapes on a reel to reel quit looking for a straight wire with gain. You need some 2nd order harmonics!😆"

Hello kw6,

      I noticed you posted the exact same comment on an older class D thread that's still active on 11/23/20.  Here's a link and your comment along with a very good reply from @atmasphere are toward the bottom of this link:
https://forum.audiogon.com/discussions/class-d-technology?page=11

     Here's a copy of atmasphere's reply just for convenience and to refresh your memory:


atmasphere8,933 posts11-23-2020 11:07am

Bottom line is until we can get rid of the nasty 3rd harmonic distortion in class d our ears will always prefer the cozy 2nd harmonics that tubes generate

@kw6 Actually the human ear/brain system treats the 3rd harmonic the same as it does the 2nd, in that its relatively inaudible and adds to a bit of what audiophiles call 'bloom', 'warmth' and the like. The other odd ordered harmonics are not so benign!

     Did the initial response from atmasphere, who is a long time member here along with being the owner and amp designer of the highly respected tube amplifier manufacturing company Atma-Sphere, not sufficiently answer your question? It seems to me that your initial question has been clearly and fully answered.  Do you disagree?
     Or is there another reason you seem intent on spreading disinformation concerning class D amplification?  Would you like to clarify why you're repeatedly asking this same question on at least 2 class D threads here on Audiogon and implying there's a fundamental problem with class D technology? 
     Would further research reveal even more evidence of your false implications on Audiogon and possibly other online audio forums?
     I just happened to discover this instance of your apparent class D subpterfuge  because I was participating on both of these threads simultaneously.

Thank you,
    Tim

I found this post by seanheis1 from another class D thread to be very interesting and relevant:


 
seanheis1 OP434 posts



01-04-2017 3:51pm

Fact is the times have changed in audio. Digital is blossoming with tech that combines dac, amp, preamp, room correction etc.. all into one or two boxes keeping the signal all digital up until the point the signal is sent to the speaker.

Read all the recent reviews of my Lyngdorf 2170 or the Exogal Comet and Ion amp. The future is here right now.

Grannyring - there really hasn't been much discussion on this thread about digital Class D...mostly analog Class D using modules from Hypex and Ice...a few from Pascal & Abletec. Your Lyngdorf appears to use the TI Equibit technology, which combines amp & DSP. Very interesting stuff.     http://www.futurlec.com/News/TI/AudioSolution.shtml