AFAIK, class C is a poor choice for audio (better for FM transmitter).Hate it when I make stupid mistakes like that.
Class D Technology
So I get the obvious strengths of Class D. Efficiency, power output & running cool which allows for small form factors. I also understand the weaknesses somewhat. 1. Non-linear & lots of distortion that needs to be cleaned up with an output filter.
So my question is, if it weren't for efficiency & power, would there be any reason to own a Class D amp? Do they beat Class A in any other categories that count for sound quality?
So my question is, if it weren't for efficiency & power, would there be any reason to own a Class D amp? Do they beat Class A in any other categories that count for sound quality?
527 responses Add your response
Class C is great for ham radio! Ha! Folks, most class D designs are really a type of Single Ended amp. Something we've been going back to last couple of decades. This may explain why D is finally getting there. The snag class D still deals with is the control loop (feedback). We're still learning - so expect class D to get better and better. Sound quality depends on the inherent linearity of the amp w/o feedback. Tube guys know this well. Some of us are trying to do this concept with D. Won't happen overnight. A is just another version of A/B. Bias is used to increase the operational linearity of the devices. It works to a point. Cost is serious $$$$ and heat. Some day, D will incorporate all these factors that are pluses in other topologies. Then we'll all stay cool dudes.... |
I feel very well qualified to report on my time ( 10 yrs.) with a pair of Class D, Red Dragon Leviathan monoblocks. I LOVE them. ... I don't hear the harsh and dark that guidocorona reports. The reviews were also just shy of stunning when new. With no mention from any one of such shortcomings. I have been using an EAR 868 pre though. And it is a very nice "warm","sweet" and "tuby" tube pre. So I confess to "tuning". When I used a Mark Levinson 380S it was more bright. But not fatiguing , or harsh in any sense. I will tell you that the sound is my number one criteria. However their absolutely effortless control, and comparatively light weight are very nice pluses. My current listening room is mid sized, and the amps are great space savers. I have some Bob Carver Cherry 180s that I haven't even set up because I am so happy with the Leviathans. And I would also love to have a pair of brute solid state monos. But every time I look to see what the weight is. And going over 100 lbs. makes me think what I'd pay to not have a slipped disk. ... I'll still go big SS when the opportunity presents itself. But if setting up a surround sound system, I'd have to sample the new line at Red Dragon. ... I'd buy them by the bunch !!!! I don't know about all the other stuff out there. But RD is OK+++. |
Hi keeponrockin, it is fabulous that you had an exceptional experience with the Leviathan. Admittedly, I audition Leviathan several times at length, using my standard test tracks of piano, chamber, jazz/Krall, orchestra, and sax/vocalists, but only at RMAF.... What often happens at shows is that manufacturers bring along brand new devices fresh off the factory floor, with little or no break-in.... So, it is possible that I was experiencing the limitations of units which were not properly broken in. Regards, Guido |
Hi RSA, you are safe with Bel Canto... Like Merrill Audio, Rowland, Theta, and D-Sonic, they are reported to make make wonderful amps. Several years ago I review the now withdrawn Bel Canto REF1000 Mk.2 monos for PFO.... Here is the article: http://www.positive-feedback.com/Issue43/bel_canto_ref1000.htm |
call me stupid but what do you mean by a "Output Filter" ? A L/C for you amp? Thanks, I am thinking about a Bel Canto but have never heard them.You might want to hear them first. They are not for everybody. Most people feel that they are incredibly clean sounding with great control of the bass. However, some people also feel that they sound lifeless in the midrange compared to high end linear amps. Of particular importance is the module that is being used. Of less importance is the brand name responsible for putting the module and power supply in the case and tweaking the input stage to create a house sound. Tube preamps can help with the lifeless sound, although some prefer that sound. Good luck. |
seanheis, I thought that anyone wanting to learn more about class D amplification may want to hear from the horse's mouth,inventor of UcD (Universal class D) and the much newer NCore class D devices Bruno Putzey,, from interviews he has given on the links below. http://ultraaudio.com/index.php/feat...audio-part-one http://ultraaudio.com/index.php/feat...audio-part-two He discusses many interesting specifics about class D in a manner that is articulate and informative without needing to be an electrical engineer to understand. I found his discussion of the feedback loop (" there is no such thing as too much feedback") and switching frequencies ("A reasonable switching frequency for a class D amplifier is just under 500khz") especially relevant to this thread's content thus far. Please read these attachments. Thanks, Tim |
I’m not sure if anyone has covered this (I didn’t read all 8 pages), but if one is chasing greater efficiency than Class A without sacrificing as much fidelity as Class D tends to do, Class G and H amplifier tech would seem to be the best choice. For those unfamiliar with this tech, voltage is constantly varied across multiple supply rails to the output transistors, allowing current to flow based on the constantly changing demands of the source material. This greatly improves both efficiency and headroom, and perhaps most relevant in this discussion, allows the amps to run in pure Class A bias for a relatively large portion of the listening range with massive Class A/B power reserves for handling peak demands. Arcam (Class G) and AudioControl (Class H) are the most accessible options for this tech, though I’m sure there are others out there as well. About the only downside is that it’s an expensive design compared with more traditional tech, but as we head into the future where efficiency requirements are becoming more stringent, this is the best option I see for preserving audio fidelity. Just my .02. :) -David |
Thanks for the link Tim. This quote tickled me. Much the same with converters. If you know exactly what to look out for in a chip, you can find chips that are really suited for use in a $1000 product that, for the price, will offer fantastic performance, simply incredible value. Speakers ditto: You wouldn’t believe the performance of some $10 drive-units, but if you’re hung up on exotic cone materials, you just won’t discover those. |
savdllc I'm afraid I don't buy your premise that class D is always behind A/B, or even behind class A universally. I'm listening to class D precisely because they were as good as heavily class A biased linear amplifiers, though just like linear amps, I can see them having limitations with specific difficult to drive speakers. Further, I don't buy that ranking tech in order really helps us understand sound quality very much at all. I assure you I can make a terrible sounding class A amplifier. :D I think while it's cool, and fun to understand what's different, and how compromises and problems are solved, and how dac X is different than dac Y, I'm not one who puts this above personal impressions. Best, Erik |
savdllc, You stated: " but if one is chasing greater efficiency than Class A without sacrificing as much fidelity as Class D tends to do, Class G and H amplifier tech would seem to be the best choice." This statement implies that class D requires you to sacrifice significant fidelity when compared to class A/B. As a user of various decent quality class A/B amps exclusively for about 30 yrs (beginning with Adcom and then McCormak and most recently Aragon) before trying various good quality class D amps (beginning 2 yrs ago with a budget ClassD Audio SDS440SC then an Emerald Physics EP-100.2SE and currently D-Sonic M3-600-M mono-blocks), I can assure you I never felt I was sacrificing any fidelity with class D. With all 3 class D amps I actually experienced quite the opposite; immediately noticing significant improvements in noise level, bass response, mid-treble fidelity being very similar to class A/B with my initial budget class D and clearly superior to my former class A/B amps with my admittedly better quality most recent class D amps. I know there are many here on Audiogon who have discovered switching to class D is all gain with honestly no pain. I'm concerned that comments like yours, and other posters earlier in this thread, may give readers the false impression that switching to class D involves some sacrifices in sound quality. I want to make it clear to everyone considering a switch from class A/B to class D amplification that these sort of comments may have been accurate for some early lower quality class D amps but are definitely not valid for current good quality class D amps. Once you've experienced the extraordinary improvements a good recent class D amp will make in your system, you'll begin to realize how inaccurate, no longer relevant and simply untrue these types of comments are. I can only rationalize these sorts of comments by assuming that these individuals have obviously never auditioned a recent good quality class D amp in their system or anywhere else. Although it's possible they're just parroting comments they've heard years ago about early examples of class D. I'm grateful I ignored these class D myths and opted for an open minded home trial and suggest others do the same. Concerning class G and H, I have never heard either but I'm interested in hearing them. Being an extension of class A and A/B amps, however, I would expect them not to have the same advantages of reduced weight and size that class D allows. Thanks, Tim |
I'm concerned that comments like yours, and other posters earlier in this thread, may give readers the false impression that switching to class D involves some sacrifices in sound quality.Class D did exactly that at my house. I want to make it clear to everyone considering a switch from class A/B to class D amplification that these sort of comments may have been accurate for some early lower quality class D amps but are definitely not valid for current good quality class D amps.Not sure what you consider "current good quality class D amps" but to confirm, my comments are based solely on comparisons with the Ncore NC1200 Acoustic Imagery Atsah monoblocks ($10K/pair). Once you've experienced the extraordinary improvements a good recent class D amp will make in your system, you'll begin to realize how inaccurate, no longer relevant and simply untrue these types of comments are.Again, not here. My evaluation started with four amplifiers, all of which I owned and the Class D Ncore amps were the first eliminated. There were indeed sonic trade-offs and the Ncore amps did some things quite well (bass, tone, power, body and lack of noise). For some, those attributes at would be enough since they were enjoyable to listen to but, for me, there was a missing musicality factor that ended up being a deal-breaker, at least in my system and to my ears. The Atsahs, like Merrill's Veritas, use the stock NC1200 amplifier and power modules. I would like to hear those amplifier modules with a linear power supply as in Theta's Prometheus and I would also like to hear the NC1200 modules with an input buffer, as some are using like, I believe, Mola Mola in the Kaluga. I can only rationalize these sorts of comments by assuming that these individuals have obviously never auditioned a recent good quality class D amp in their system or anywhere else. Although it's possible they're just parroting comments they've heard years ago about early examples of class D.Again, be careful painting with a broad brush. Some of us have indeed auditioned and even owned amps considered to be "good quality Class D amps." I ended up voting with my wallet. Class D amps are obviously getting closer to sounding as good as really good Class A or AB amps and in some specific implementations may sound better. The Atsahs were good sounding amps but they were not as good-sounding as my other options. There have been many positive reviews of the NC1200-based amps but for another perspective, read near the end of the linked review of the Mola Mola Kaluga. http://www.monoandstereo.com/2015/08/mola-mola-makua-and-kaluga-review.html |
Absolutely, "musicality" is indeed subjective . I am not trying to convince anyone. My intention is to point out the inaccuracy of making broad generalizations about folks here who still like the sound of their Class A or AB amps better than the Class D amps they have compared against, and how that doesn’t necessarily mean they are only comparing against old Class D technology or less expensive Class D implementations. I may not have defined "musicality" adequately but would add, the sound of the Mola Mola Kaluga described in the review linked to my prior post is not unlike what I heard from the Atsahs. Again, I thought they were good amps, just not as good as my other options. |
I’ll repeat what I’ve said several times on this forum. I had a Jeff Rowland Class D Continuum S2 Integrated amp and to my ears it was musical and did all of the "audiophile" things very well. I rate it above every amp I’ve every had in my system; except the Class AB Jeff Rowland 625 S2. To be fair I have the 625 S2 with a Jeff Rowland Corus preamp and together they are in a totally different price category. In my system the 625 S2/Corus is just more musical and I submit highlights the shortcomings of Class D. At least in direct comparison with products made by the same manufacture. |
There have been many positive reviews of the NC1200-based amps but for another perspective, read near the end of the linked review of the Mola Mola Kaluga.This review perfectly describes my experience with ICE Power. In learning about Class D, it appears that after the linear signal is destroyed and turned into a saw tooth wave form, the output filter? tries to put the signal back together...doing an incredible job considering the complexity of this task...but ultimately is unable to restore micro details to recreate the original signal...which people such as myself notice very quickly, while others either don’t notice or enjoy the new coloration. Perhaps my understanding of Class D that I mention above is incorrect and someone can correct me. |
Hi Richard, actually what the performance comparison between CS2 and the M625S2+Corus combo highlights is that the latter com bo was designed to a price point Three times higher than Continuum S2, and that it contains circuit sophistications not possible to meet CS2’s pricepoint. Were you to compare the performance of the class A/B M625 S2 to the class D M925 monos flagship, which costsover three times as much as M625 S2, you might be tempted to draw an equally unwarranted conclusion that class D is inherently superior to class A/B... Which of course would be a fallacy as well. |
In learning about Class D, it appears that after the linear signal is destroyed and turned into a saw tooth wave form, the output filter? tries to put the signal back together...doing an incredible job considering the complexity of this task...but ultimately is unable to restore micro details to recreate the original signal...which people such as myself notice very quickly, while others either don’t notice or enjoy the new coloration.It is silly, to avoid using stronger word. You originated this thread pretending you want to learn about class D, while knowing you hate it. I will remember your login and will be careful to answer your posts next time. |
It is silly, to avoid using stronger word. You originated this thread pretending you want to learn about class D, while knowing you hate it.I've learned a ton about Class D from this thread and I appreciate everyone's input (including yours). I began this thread after having a poor experience with Ice Power. I wanted to like that tiny powerhouse and kept trying to talk myself into getting used to its tonal qualities. My goal has been to learn about Class D in general as well as limitations and strengths of the technology. It's hard to not step on toes when seeking to uncover information that is potentially upsetting to promoters of the technology. I would not have began this thread if I had given up on this technology as the internet has enough trolls. Happy New Years to all classes of amp lovers. |
You originated this thread pretending you want to learn about class D, while knowing you hate it.Maybe it's some that are so pro Class-D as it stands, and can't/refuse to see that it's maybe it's not become of age yet. If they can concede that Technics with their SE-R1 are showing the way in the area of switching noise frequency development, maybe then there'll be an even faster development in that area by other class-d manufacturers demanding to have those components to make it happen. Cheers George |
mitch2, My comments in my previous post were solely in response to savdllc's/David's post on 12/31.and were not directed at you at all. After reading your post and the review you linked to on the Mola-Mola class D preamp and amps, you are clearly not included in the group of posters that have never heard a good class D amp in their system. I concede your point that some have compared class A and A/B amps to 'current good class D amps', not just the early class D amps,and still preferred the class A or A/B amp. In regards to what I consider ' current good quality class D amps', I would include any amps utilizing the NCore-1200 modules (Acoustic Imagery Atsah, Merrill Veritas, Theta Prometheus, etc.) as well as those utilizing Abletec and Pascal power modules (Marten, D-Sonic and Rowland). There are also other current good quality class D amps such as H2O, W4S, Red Dragon and Bel Canto. Sorry, I probably missed a few other current good quality class D amps,too. Your attached review of the Mola-Mola preamp and amps were one of the few reviews I've seen on the Kaluga monos that was not extremely positive. The review was not totally negative but it seemed to me like the reviewer had such high expectations going in that only near perfection would result in a positive review. Both you and the reviewer mentioned 'a lack of musicality' which is a quality that is very subjective and uniquely perceived by each listener. Regardless of how each person defines it and perceives it, however, I think 'musicality' is probably the most important quality a home music system needs to possess. I understand it's a quality you require in your amp and I feel the same. I believe we both perceive the bass,power, tone, body and lack of noise in good class D amps (NCore-1200 based amps in your case and Abletec based amps in my case). but you also perceive a lack of 'musicality' whereas I do not. As a result, I'm much more enthusiastic about good class D then you are. You're very pleased with your class A or A/B amps and I'm pleased with my class D amps. I'd call that a win-win scenario, congrats. I believe no amp technology has a monopoly on good sound quality and think we both agree that class D is not right for everyone. No big deal, right? Tim |
All is good Noble100, I can certainly understand how folks like the Ncore amps so much since, in my system, they did a lot of things right
(bass, tone, power, body and lack of noise). However,
even with very good and highly regarded amplifiers, seemingly minor sonic characteristics can affect one's level of satisfaction with how their system sounds. Everybody has their own personal "right" sound. I really wanted those to be my "final" amplifiers because they had the desirable combination of high power, high input impedance, balanced operation (my system is fully balanced), small size, low energy usage, low noise, and the ability to remain powered up all the time. Unfortunately, my preference was for a pair of large, heavy, and hot Class A amplifiers. |
That is trollingOnly in your mind, because you refuse to accept that the higher switching frequency has yet to be realized, and you can't hear anything wrong with it where it is at the present. Even though companies like Technics are showing the way and striving for higher frequencies, with their very expensive SE-R1. And as far as not giving any positive post go, I said they have a bass control that can't be equaled, and I'll be the first to get the newer generation of higher switching frequency ones, when they evolve which will fix the problems that many hear in the upper mid and highs, and you obviousely can't. Cheers George |
mitch2, Thank you for your reply, I agree with all you stated and now have a better understanding of your thoughts, situation and position. I'm glad we were able to clarify and think it's a good sign that we were both able to find amplification that we're pleased with utilizing different amp types. Later, Tim |
Hi George, I am amongst those who cannot hear any displeasing high freequency artifacts or limitations in some -- and by no means not all -- class D amps in current production. I would include at least: Rowland M925 and 825 (both based on NC1200), Continuum S2 (Pascal M2-Pro). Bel Canto Black (NC1200 derivative). Merrill Veritas (NC1200). Conversely, a number of older amps, like the old Rowland M501 and 201, and the NuForce did display modrate to severe audible limitations. It is also worth mentioning that even the best class D amps can sound limited, oscillating between screetchy and tubby until break-in is complete, which unfortunately can range between 600 and 2000 hours, depending on power conversion module and amplifier design... THus, breaking in a class D amp can be an exercise in extreme patience and anxiety control *Rolls eyes!*
Yet, As you are mentioning the switching frequency as a probable cause of limitations that you perceive, would is your estimate of the switching frequency one would require to push any such artifacts into the inaudible stratosphere for good? Saluti, Guido |
In learning about Class D, it appears that after the linear signal is destroyed and turned into a saw tooth wave form, the output filter? tries to put the signal back together...doing an incredible job considering the complexity of this task...but ultimately is unable to restore micro details to recreate the original signal...which people such as myself notice very quickly, while others either don’t notice or enjoy the new coloration. The opening statement here is false. Here's how class D works: There are essentially 3 building blocks: 1) the triangle wave generator (sets the 'scan' frequency) 2) A comparitor, the compares the incoming audio signal to the triangle wave 3) the output section. This is the power transistors that switch on and off, and any circuitry needed to drive them The sawtooth or triangle wave generator is running all the time. The comparitor is too- taking the audio signal and turning either on or off depending on the state of the triangle wave and the audio signal at any given time- the output is a series of pulses of varying width, which are used to switch the output transistors either on or off. This technique is called 'Sigma Delta' and is a means creating the output pulses of varying width so is also known as 'pulse width modulation' The scan frequency is a function of the triangle wave generator. Some ICs can't make a good triangle wave at higher frequencies so quite often this can be the reason the scan frequency is limited. The other reason might be the output transistor's ability to switch (these days its pretty easy to find inexpensive parts that can switch at well over 1 or 2 MHz...). There is usually a filter at the output of the amp to filter out the scan frequency. Once that is filtered out, all that is left is a much higher current version of the input signal. The scan must be kept constant to maintain fidelity. The output devices can sometimes stay on longer than they are supposed to (typically they take longer to turn off than to turn on) so they can both be conducting at the same time. If this happens, you get a phenomenal called 'shoot-through current' which can heat up the outputs really fast, so sometimes additional circuitry is used to make one transistor wait until the other is off before it turns on. This wait time is called 'dead time'. The longer the dead time the higher the distortion. Dead time is usually needed at higher switching frequencies, so you can see that the need to go to higher frequencies to reduce distortion (and increase resolution) is hampered by the fact that more dead time might be required, which increases distortion. So you can see that the designer has to weigh options! This is it in a nutshell. Some things are glossed over and others omitted entirely, but if you know what is written here then you have a pretty good idea of how they work. |
"Maybe it's some that are so pro Class-D as it stands, and can't/refuse to see that it's maybe it's not become of age yet. If they can concede that Technics with their SE-R1 are showing the way in the area of switching noise frequency development, maybe then there'll be an even faster development in that area by other class-d manufacturers demanding to have those components to make it happen. " Is this Technics you keep referring to class D ? Or is it a digital amp ? Totally different technologies ? |
I am not sure where obsession with the switching frequency comes from. It is inaudible while the only other thing that it might cause is filtering network phase shift - that can be beneficial since speaker has much larger positive phase shift at high frequencies. Placing nonsense about signal being "destroyed" (while SACD works exactly the same way) is trolling. In fact raising switching frequency might be harmful because of the dead time, forced by the controller to avoid shoot thru, that Atmasphere mentioned. Since this time is fixed, error it makes will be larger at the higher frequency. One might not like the sound of particular class of amplification but making pseudo-scientific explanation i plain silly. |
I am not sure where obsession with the switching frequency comes from. It is inaudible while the only other thing that it might cause is filtering network phase shift - that can be beneficial since speaker has much larger positive phase shift at high frequencies. Placing nonsense about signal being "destroyed" (while SACD works exactly the same way) is trolling.If you read my post I used a question mark and asked for clarification and correction...which Atmosphere was kind enough to reply to and correct my confusion. Kijanki, I don't think that anybody is doubting that your amplifier sounds brilliant to you. At the same time, I think it's okay for others to be less satisfied about what they hear. Don't get me wrong. I want a tiny powerhouse amplifier that sounds brilliant to my ears as much as the next guy. Class D is the future and there are a lot of audiophiles sitting on the sidelines, waiting for the technology to mature. We need early adopters to buy into the technology so I'm thankful that the modules are good enough or even perfect right now for many people. |
Kijanki, I don't think that anybody is doubting that your amplifier sounds brilliant to you. At the same time, I think it's okay for others to be less satisfied about what they hear. Don't get me wrong. Class D is the future and there are a lot of audiophiles sitting on the sidelines, waiting for the technology to mature.+1, and the only way is to speak up and get it done. So far Technics is leading the way. Cheers George |
@erik_squires and @noble100 , I'm glad you both have found systems that you are happy with, and you are certainly correct in that there are some great Class D options available on the market - I do not believe I stated anywhere in my post that Class D in universally inferior to A/B. What I did state is that Class D designs tend to sacrifice fidelity in favor of efficiency, which is true in most cases. Are there exceptions? Sure, though that's not really what the OP was asking; his question was not if the best Class D designs can compete with Class A/B, it was: "If it weren't for efficiency & power, would there be any reason to own a Class D amp? Do they beat Class A in any other categories that count for sound quality?" And while audio quality is somewhat subjective, I think you're going to be hard pressed to argue that even the best Class D amps will rival the best Class A amps on the market. I brought up Class G and Class H as being potentially better options in the ongoing search for increasing efficiency while preserving fidelity, which from a sheer technological and design point of view, is hard to argue with when it comes to reproducing full-range audio. The only downside is cost, as it's a much more expensive technology than Class D, and that may well be what prevents it from ever becoming a mainstream option. Anyway, I've no wish to start an argument with you or anyone else - I was simply trying to share my thoughts on the subject based on my experience as both a long-time enthusiast and owner of a home theater company. Cheers, -David |
"If it weren’t for efficiency & power, would there be any reason to own a Class D amp? Do they beat Class A in any other categories that count for sound quality?"That is the debate, my answer is no, not yet, (except in the bass & upper bass). And it’s not because of the power, but more the damping factor (low impedance output) which some say is aided by of gobs of feedback. Cheers George |
If it weren't for efficiency & power, would there be any reason to own a Class D amp? Do they beat Class A in any other categories that count for sound " Let me try to respond to the question posed by the OP in the crispiest way I can: 1. I am deeply dissatisfied with at least 90% of amps on the market that I had the fortune, or the misfortune, to audition, regardless of class of operation. 2. I have selected my class D amps because I fell in love with their total audible performance, for every parameter.
4. I found less than a handful of amps that enthrolled me as much, or almost as much... The leading contender was made by Solution... Enchanting class A/B amp, which I would put more or less at par with the classs D Rowland M925 As for which class is inherently audibly superior .... It is an absurd question, which has no meaningful answer. On the other hand, I grant you that when class D misses the musicality mark, either because the amp is not properly broken in, or because of inherent design flaws/limitations more common on older designs, it has the ability of outschreetching and outtubbing most everything on the market... The most unendurable listening experience for me was in fact that of a lower cost class D amp... Closely followed by that of an uber-stratospheric SS class A/B system... Conversely, even the worse uber-expensive tubed amp I heard, was only marginally worse than totally uninspiring.
G. . |
Don’t listen to the negative propaganda especially from just one or two who repeat the same thing over and over. Just try them for yourselves if interested and see. Myself, I’ve had way less trouble finding top notch sounding Class D amps than others. Will probably never go back to anything else. If I had unlimited budget and/or went only with very easy load speakers, perhaps it might be easier to find other amps to match overall performance and sound quality I have experienced with Class D. But even so I have no reason to ever go back to anything else. My Class D amps do it all as well or better than anything else I have heard in recent years. If I were to seek a particular unique flavor of sound only available with a tube amp, maybe. A good Class D amp is like a high performance car engine. it makes the entire experience a lot more effortless and enjoyable. Those who discount or ignore the advantages inherent in newer more efficient and overall higher performance Class D technology are doing others a disservice. I know I’m glad I went with my gut which told me to actually see what this popular and innovative newer technology is actually capable of before resorting to older more familiar solutions that never seemed able to fit the bill for me 100%. |
savdllc (can’t "at" you for some reason) you wrote: What I did state is that Class D designs tend to sacrifice fidelity in favor of efficiency, which is true in most cases. This is the bias I was trying to answer, my apologies I did not connect my statements more clearly to your writing. I am unable to support this statement based on any evidence at all. I do believe that Class D is in a much wider quality range of products than Class A. By this I mean from cheap portable music players to high end. Class D is, numerically, overwhelmingly dominant and across every market segment, while the ONLY place in audio I know of with Class A being produced today is high end, often mono-blocks. (There’s probably some Bugatti with Class A amps, but lets get real) This may lead us to make unfair apples to oranges comparisons which don’t actually tell us much about the overall potential of Class D. At the high end, I see no sacrifices being made for Class D except to my carbon footprint. I DO hear differences in amplifiers. However to hear those differences and say "OH, well Class D is inferior, so the A/B amp must be better sounding" is an snobby prejudice. There are even some strong benefits, as some have very high damping factors (output impedance) and therefore more consistent performance across speakers. I think that the subjectivity of the "high-end" can be quite trendy, or go pretty far from neutrality. If that keeps a Class D from reaching top-tier status, then it's just a matter of time before a vendor creates the right input buffer for you. Again, to everyone, please please buy what you like to hear, but let’s not use cost as our golden calf of determining what’s best. Best, Erik |
mapman Those who discount or ignore the advantages inherent in newer more efficient and overall higher performance Class D technology are doing others a disservice.Don't be silly. Those who exercise their personal preferences here do a disservice to no one - except, perhaps, themselves. No one here owes anyone else anything. |
David, My main points of contention are with your earlier post in which you implied that class D amps have inherent compromises in sound quality and your last post in which you said class D sacrifices sound quality for efficiency. You don't specify what these supposed compromises are and I consider it irresponsible to mention sonic compromises in class D as if they were well known and givens. As a result, I feel the need to respond by stating that I noticed no sonic compromises when I replaced my class A/B amps with class D amps. In fairness,mitch2 did state in a subsequent post to yours that, when he compared some class A amps to the very good class D Acoustic Imagery amps (based on the NCore 1200 module), he thought these class D amps had some very good qualities (bass, tone, power, body and lack of noise) but they lacked the 'musicality' that he perceived with his class A options. Fair enough, in his system he preferred the class A ( not class A/B) amps because they sounded more 'musical' than the class D amps. This 'musical' quality, by which I think he means that his system portrays a realistic sense that he is in the original venue listening to the actual performance, is obviously a very important quality to him as it is to me. While I didn't directly compare class D amps to class A amps in my system I did compare them to my former class A/B amps. I do not perceive a lack of 'musicality' in my class D amps (D-Sonic M3-600-M mono-blocks) in my system and room. I have no interest in arguing the point or about why we had such different results. I just think we're both fortunate to have found such good amp solutions and we both should enjoy our systems no matter what type of amps we use. The main point I want to convey is that current good quality class D amps perform very well. Based on my experience they outperform my former good quality class A/B amps- Adcom, McCormak and Aragon-in all categories that count for sound quality. Getting back to the OP's original question: "If it weren't for efficiency & power, would there be any reason to own a Class D amp? Do they beat Class A in any other categories that count for sound quality?" My answer is I do not think class D amps beat Class A in any categories that count for sound quality yet, based on others opinions who have compared them directly in their systems and my auditions of class A amps in dealer systems. However, class D amps have so many other advantages over class A (reduced price,electricity consumption,heat, size and weight) that some may opt for class D anyway. Then there are class G and H amps which I'm keeping an open mind about until I learn more and hopefully hear them. Other than the above, David, I have no issues with you. However, I am a bit curious whether or not you utilize or offer class D amps in your HT business. I certainly have no issues with you voicing your opinions just as I think you have no issues with others voicing their opinions. After all, I think that's the whole purpose of this very good forum. Thanks, Tim |
