@erik_squires
"Still, proof is in the listening."
Always!
"Still, proof is in the listening."
Always!
Class D is just Dandy!
I thought it was time we had a pro- Class D thread. There's plenty of threads about comparisons, or detractors of Class D.
That's fine, you don't have to like Class D amps, and if you don't please go participate on one of those threads.
For those of us who are very happy and excited about having musical, capable amps that we can afford to keep on 24/7 and don't require large spaces to put them in, this thread is for you.
Please share your experiences with class D amps!
That's fine, you don't have to like Class D amps, and if you don't please go participate on one of those threads.
For those of us who are very happy and excited about having musical, capable amps that we can afford to keep on 24/7 and don't require large spaces to put them in, this thread is for you.
Please share your experiences with class D amps!
847 responses Add your response
@erik_squires That’s not what’s being done here. DSP is used entirely for electrical phase and amplitude. The actual speaker/room response is not considered. Quite a heavy handed approach to making an amp perform like an ideal voltage source.That may be so as to avoid using global loop feedback, which is known to exacerbate higher ordered harmonics. Speculation on my part... |
This is a brief tangent from the current topic but I wanted to give an update to those that helped me in selecting a class D amp. I was fortunate enough to pick up a Red Dragon S500 power amplifier from a fellow Audiogoner and I could not be happier! The amplifier is truly all that it has been touted to be. Effortless delivery of power, clean, smooth, extremely detailed with excellent separation but without harshness. I could go on and on, but the end message is: class D is the real deal. Even to my untrained ears there is a noticeable difference in the "feel" of the music (please excuse the lack of the usual audiophile adjectives). I think one of the most amazing things is how good it sounds even though the rest of my system (other than my ls50s) can be considered low-budget components! Thanks again to all of you that gave input to guide me along this class D odyssey! |
Hi Erik, i had home demoed a Peachtree Audio Nova 125 SE and a Rogue Audio Sphinx v2. Although I wasn't able to do a side by side comparison, from what I recalled, the Red Dragon sounded the best. I also had my old Qinpu A1.0x integrated that I had in my system immediately prior to inserting the Red Dragon and it was definitely the better of the two. Of the 4 amplifiers, the Red Dragon had the best overall sound and the most enjoyable sound. At some point (perhaps Black Friday deals?) I would like to upgrade my DAC, and the preamplifier since both are low budget (but decent) components. But I figured I could build the system piece by piece as the budget allowed. I'm just very grateful that I was able to obtain the amplifier that had won so many accolades! |
Hi autre, Congrats on choosing the Red Dragon S500 stereo amp. A very fine example of a class D amp done right. It utilizes the newer Pascal S-Pro-2 power module that is also utilized in the Jeff Rowland 525 bridgeable stereo amp and the Rowland Continuum 2 integrated and the Gato Audio integrated. These modules have an enhanced and patented class D technology named UMAC, which integrates the Switching Mode Power Supply (SMPS) with the Switching Output Stage on one board and not on separate boards like the high-end Hypex NCore amp implementations in which the Hypex NCore 1200 SMPS and NCore 1200 Output Stage are on separate boards. This integration enables the Pascal S-Pro-2 to be the most compact 1,000 watt class D professional amp module on the market. More importantly, however, is how does this Red Dragon S500 implementation of the Pascal S-Pro-2 power module combined with Red Dragon's custom input buffer stage actually sound? From the many reviews I've read on this amp at 6Moons, Dagogo and Audioholics, along with your very positive reports, it's abundantly clear this is a high performance amp. Unfortunately, I've not yet been able to audition this amp in my system although I was very close to buying a pair of Red Dragon M500 MKII mono-blocks based on their excellent reviews and the very cool Red Dragon logo that lights up on the front of each amp when active (in red of course). The black units were out of stock at the time and I decided to buy a pair of D-Sonic M600 mono-blocks instead. I've been very pleased with the D-Sonics but would still love to try the M500s or S500 in my system just to determine if I made the right choice. My current opinion is that these are all very good class D amps that I'd be pleased with in my system. I'm continuing to enjoy learning about and understanding each individual amp/tree in the exciting and constantly improving class D forest. I've also continued to fail to detect even a whiff of a sniff of an inkling of any sonic anomalies in any of my 4 class d amps caused by their mid 500 Khz switching frequencies. Is the 'Wonder From Down Under' still propagating his unsubstantiated and debunked theory that class D switching frequencies need to be over 3 Ghz to avoid sonic anomalies in the audible range that no known human has ever claimed to have actually heard? Enjoy autre, Tim |
Recommended Components: 2017 Edition Integrated Amps & Receivers Read more at https://www.stereophile.com/content/recommended-components-2017-edition-integrated-amps-receivers#6e... Sterophile has two picked two “Class D” integrated amps to receive their highest “A” rating for 2017. i own one of them; the Classe Sigma 2200i. Great sounding amp and massive power output 200W x 2 into 8ohms and 400W x 2 into 4ohms. Clean, sweet, refined sound with tone controls, room equalization, network streaming, internal DAC, AirPlay...blah, blah, blah, |
Although I am the happy owner of a class A tube beast that weighs almost as much as me, I'm curious about class D amps. I'm not getting any younger and handling my amplifier by myself is becoming an impossible task. Not to mention the heat and the cost of maintenance. I've been looking at some class D amps from Ghent Audio, Temple Audio and Class D Audio. I'd like to buy something under or at around $1000. Ghent Audio uses the ICEPower and the other two are using the Tripath. What are the main differences? Does anyone compared any of these three brands? Opinions? |
Hi @migueca As I have written elsewhere, the ICEPower AS and ASP series is a very modern sounding amplifier. No extra warmth or juiciness, but not stark sounding either. To my ears it is the equal of the Parasound A21/A23 amplifiers, and very similar sounding. I cannot hear a difference on my speakers. Quite and powerful sounding. You should also try NuForce, which uses a very interesting hybrid approach. Best, E |
Erik, I too am a big fan. I have a PS Audio DirectStream DAC, but found it didn't sound so good decoding MQA (even when Tidal did the unfold), so I bought a Brooklyn for MQA. I hope they will have a booth or a dealer at the Capital Audiofest, plan to attend this year, hope to hear the new amp, if it's on display. Evan |
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I have been running an old Class D Rotel RB 1072 for years. I slowly upgraded everything around it by adding Sonos (wyred4sound mods) Wadia 321 DAC Rouge Audio RP1 (tubed pre) Focal Aria 936 Each of the upstream upgrades were a long range plan to try and stay with a class D amp. Finally about 3 weeks ago I tried the new PS Audio Stellar S300 amp. I just called them to inquire but when they offered a good price on the Rotel as trade in I took the hook. I think they got one of the engineers from Classe' to do the ICEpower implementation. I am completely satisfied with the improved sound (proly a slam dunk considering where I was). I have pretty much turned off my Velodyne Micro V. Enjoy the tone and increased realism and sound stage. Running a little warm but nothing like a class A/B Unit. Now I can turn my attention toward my TT or SACD player. If you have an amp to trade in, the S300 can be a real value. Let the crack habit continue. |
I experimented with two Class D amps in my system; Merrill Audio's Taranis and Digital Amplifier Company's Maraschino Monoblocks. My system consists of an Esoteric X-03 SE CD/SACD player -> PS Audio DirectStream DAC -> amp -> Reference 3A DeCapo BE. I chose Tommy O'Brien's Cherry Amp Maraschino monoblocks over the Merrill Audio Taranis. Nevertheless I found both amps to be detailed, powerful, and musical...albeit the Taranis more powerful at 400WPC. The Cherrys are small, efficient, and at 6"x6"x8" easy to move around; the Taranis is a single-chassis configuration. However the Taranis' single-chassis configuration did not figure into my decision-making. Tommy encapsulates his Maraschino models in their own shielded enclosure, mounted atop a marble block for stability, and separate from their outboard power supply. I like that the amp is contained in its own housing. IMO it minimizes interference between the amp and power supply. Taranis probably does as well but w/ the Cherries, I can verify the separation. Each Cherry amp was meticulously packed, w/ its accompanying ps, in separate boxes. DC cables (ps to amp) are included, as is a pair of RCA to Balanced adaptors...how thoughtful is that? Neither the Taranis or the Cherry amps sounded their best out-of-the-box. However after 48hrs of continuous power with about 10hrs play-time in between, the rough-edges were gone. That's when I realized Class D was worthy of my serious consideration...ymmv. Will these be the last amps I ever own? I don't know. I'm the unsettled-type who likes buying new gear periodically. For now, I'm happy with my purchase. If I could want for anything, it would be an increase in gain from 22db to at least 26. But I trust Tommy knows best. After all, he's likely forgotten more about amplifier design than I will ever know. In closing, if you're considering evaluating a Class D amp, I think you'll be surprised. It ain't the undeveloped technology it may have once been. Pick one of the brands bandied about here, give 'em time to break-in and make up your own mind. PM me if you want to hear more about the Taranis. |
Two more questions regarding amplification modules: How different is the sound of a Hypex from the sound of an ICEpower? Do they have distinctive sonic differences? And how important (or not) is it to have a dual-mono (in a stereo single case) rather than a single amplification module to produce stereo? |
I don't think the case makes as big of a difference as the power supplies. Both ICEPower and Hypex allow you to use a single power supply for 2 channels. This has potentially two benefits: - Headroom - Channel separation Lots of good stereo amps share a single power supply though, so having dual-mono power supplies is by no means an absolute requirement. Spec-wise, the Hypex modules are better at very difficult loads, like electrostatic speakers. In practice with "normal" speakers, I can tell you I have the ICEPower in my living room and cannot hear a difference from a linear A/B amplifier. I have Hypex designed amps on my desktop system, via an NAD D 3020, but this is a bit of a unique design. All I can tell you is I'm very happy with both. Best, E |
Hi migueca, I agree with Erik that the main benefits of mono-blocks, regardless of the amplifier type, are increased headroom and channel separation but with the former being more obvious than the latter. Increased headroom in an amp is mainly evident in its ability to more accurately reproduce the large dynamic range of live music. My experience is that a system's ability to quickly and powerfully reproduce musical passages that progress from soft or moderate volumes to suddenly higher volumes significantly adds to the illusion that you're listening to live music in your listening room; amplifiers without large amounts of headroom and the ability to deliver it quickly typically will not be able to convincingly create this illusion. However, there are class D stereo units available that contain 2 power modules, with a devoted power supply for each, combined in a single chassis. Some of these dual-mono stereo amps even utilize separate power chords for each channel/module. I've never compared the performance of a dual-mono stereo amp to a pair of mono-block amps but I believe most people, including myself, would be hard pressed to distinguish between the two. Technically, with mono-blocks having each channel contained in its own chassis and physically isolated from each other, it would be expected that their scientifically measured channel separation stats are superior to dual-mono stereo designs. Whether you'd actually hear this superiority is questionable. I've used 2 different stereo class D amps in my system (a classD Audio SDS-440CS and an Emerald Physics EP-100.2 ) and currently use a pair of D-Sonic M-600-M mono-blocks. I would characterize them all as having very good channel separation with a solid and stable 3D sound-stage illusion. I haven't noticed an obvious improvement in channel separation with the mono-blocks but have definitely noticed an increase in headroom and a greater dynamic range with the mono-blocks in my system. I know from your posts that you're thinking of trying out a good class D amp in your system and you're considering trying a Ghent or a ClassD Audio model. I highly recommend my first class D amp, the classD Audio SDS-440-CS. It's a true high quality bargain at only $630. It's powerful (220 watts @ 8 ohms/ 440 watts @ 4 ohms), has extremely low distortion levels, very good bass response, is very detailed and neutral in sound character with music emerging from a dead silent background. The mid-range and treble response is very smooth and never bright or harsh like a tube amp without the treble sounding rolled off at all. Here's a very accurate review from a professional reviewer: www.highfidelityreview.com/class-d-audio-sds-440c-amplifier.html They also give you a 30 day in-home trial period with a 'no questions asked free return policy' if you don't like it for any reason. Very low financial risk involved but I seriously doubt you'll want to return it. Enjoy, Tim |
Erik and Noble, Thank you for your explanations. Yes I am going to try a class D amplifier from this new generation of modules. I've had an experience some years ago with a Tripath from Dayton Audio and I must say, although cheap and not a truly HiFi piece of gear I was impressed! Now I'm obviously expecting a much higher quality from the new breed of amplifiers. I have been asking questions to many people from company owners/designers to dealers and forums members. And I'm getting solid and coherent answers that are helping me choosing the way to go. After evaluating many options I came down to three brands that are offering me what I'm looking for as a whole - price/performance/customer service. They are Class D Audio, Digital Amplifier Company and Temple Audio. They all seem to be fantastic choices, but I can only buy one and at this moment I'm closing a deal with Temple Audio - ordering the Monoblocks. Soon I'll be posting my review. Tank you for your sharing of knowledge! |
@migueca - let us know how you find them. I think you'll love them. I have some mystery monoblock class D amps that I love. Before that I had a Crown class D amp that was a great performer. But the switch to consumer monoblocks brought way more clarity, definition and power. I also have a Dayton audio class D I use for outside. It sounds great hooked up to good speakers, but these serious class D amps obviously trample all over it in terms of.. everything. |
migueca, I just read a review on the Temple mono-blocks that was very positive: www.enjoythemusic.com/magazine/equipment/0514/temple_audio_monoblock_amplifiers.htmat I've never heard any of the Temple Audio amps so I'm unable to provide you with any useful feedback. I noticed the monos are rather low powered at 40 watts/ch (the review doesn't mention whether that's into 8 or 4 ohms). I believe you know how important it is to match an amplifier's power rating and sound characteristics to your speakers and therefore assume your speakers are very efficient. Please let us know your room dimensions and what speakers you'll be using so we can offer further guidance. Thanks, Tim |
Noble, my speakers are the Zu Audio Omen Def. 100dB, very easy to drive - I am pairing them presently with a tubes SET pumping "only" 24W. That review that you mention is for the old monoblocks. The new model is 70W with standard PSU and 100 with the improved PSU. I ordered the best one. I'm expecting to get the amplifiers in 3 to 4 weeks. Then I can post a review. |
Hi migueca, Okay, 70W on the Zu Omen Defs is plenty of power; almost overkill. I don't think it's too much since it's such clean, low distortion power You're virtually guaranteed the amp will never clip and you'll have plenty of reserve power for transients. I think you're really going to like class D with your Zus and I'm certain there'll be much less heat in your room. Sorry for the belated response, I just saw your post. Have you got the amp yet? I'd like to hear your thoughts on the combo. Enjoy, Tim |
https://forum.audiogon.com/discussions/mola-mola-dac?highlight=Mola%2BMola This link is mainly about the Mola Mola pre/dac, but there are some comments about the Kaluga mono block class D amps. The Mola Mola Makua and Kaluga have just received an award from AV Tech Media as best high end pre and power amp. If you need to know any more about the Mola Mola let me know. UK Mola Mola dealer. |
Shadorne, That's not really a factoid so much as an operating principle. You make it sound as if the specifications are illegitimate, they aren't. The filter removes the noise you are talking about, so that the noise is on the inside, but not the outside (mostly). Sure, if you measure any random point inside the filter, you can find horrible looking signals with little resemblance to audio. True could be said of any DAC though. :) Best, E |
shadorne6,590 posts01-28-2018 8:06amLittle known factoid. Stereophile do similar now testing Class-D as not to upset readers with the noise on the graphs and to keep the manufacturers happy in case they may advertise. They use a very low power handling Audio Precision's auxiliary AUX-0025 passive low-pass filter between the Class-D's speaker output and the test equipment, which eliminates noise above 200kHz. On figure 3 you can see the switching noise of the 1khz test sine wave, it will be far greater if they showed with a 10khz sine wave. https://www.stereophile.com/images/218PSM700fig03.jpg Fig.3 PS Audio Stellar M700, small-signal 1kHz waveform into 8 ohms without AP AUX-0025 low-pass filter. If this noise was on test waves of the audio band like this on a linear amplifier, any tech would say it's faulty. Cheers George |
Compare the PS Audio design to the Bel Canto monoblocks: https://www.stereophile.com/content/bel-canto-eone-ref600m-power-amplifier-measurements Far lower noise and distortion. |
Heard it again, still don’t like it. Wyrd4sound and.. Veritas amps, looked cool, sound was blah to me. I like class a, or ab, even a switching class h has more feeling to the music. Something about the d sound just don’t sit right with me. It’s just.........like 1 dimensional, or no emotion to the music, a,ab,h just have a quality to them when I’m listening, I don’t get from d class sound. H class I’m referring to is my Carver sunfire. |
I have had a Nuprime class d amp for a few months now,and am very happy with it!The bass control is excellent!Im using it with a pair of 805 diamonds with great results!I tried it out with a pair of Thiel 3.7’s with great results also!I need a little more power for the Thiels I think?Im on the hunt for another class d amp for them.Im converted,class d rocks for sure! |
erik_squires OP3,082 posts01-29-2018 4:20amSorry George, as always, you are going to have to pivot from one point to another by yourself. If you need a dance partner it is not me. That's a cop out Eric, your the one who said said: " Most Class D amps I know of do considerably better. I'm more than a little surprised PS Audio put that out there." I ask again, Eric. Please show JUST ONE Class-D, with a clean 1khz sine wave, without using the Audio Precision's auxiliary AUX-0025 passive low-pass low power filter. Cheers George |
Hi.. I have been a Class A or Class A/B amp owner my entire adult life and trying to get a firm grasp on Class D amps. I have read through several threads and like many subjects this one is similarly polarizing. I'm not biased either way. Just seeking information and if I decide to change amps, getting the sound I'll enjoy. It seems there are about 3 major players in companies that actually manufacture the amp boards, and that most people selling Class D amps are buying the boards versus designing and building their own (probably some exceptions). If I am correct this is very unlike most Class A and A/B amp manufacturers. While I have never truly understood the prices attached to esoteric items, I do understand basic marketing and getting for a product what the market will pay. This may or may not be attached to the cost to produce said item. So my question is with the main boards themselves being made by a thrid party, how does one go say from a $1400 D-Sonic amp to a $5000 Bel Canto (or other similar) amp (per pair) up to a Merrill Veritas at $11K plus (pair)? I realize a nicer chassis, etc. will add cost, and same for internal wiring and external connectors but am trying to see what each make ris adding to their product to result in so many price variations when the main "guts" are so similar. Thx |
So my question is with the main boards themselves being made by a third party, how does one go say from a $1400 D-Sonic amp to a $5000 Bel Canto (or other similar) amp (per pair) up to a Merrill Veritas at $11K plus (pair)? I realize a nicer chassis, etc. In the "hiend" Class-D's there must be a huge profit margin compared to linear amps, even with the glitzy cases, as what's inside is worth peanuts compared to similar dollar linear amps. EG: The $8k Rowland Continuum S2 http://www.theaudiobeat.com/equipment/pics/jeff_rowland_continuum_2_large_inside.jpg uses one of these Danish modules http://www.pascal-audio.com/amplifier-modules.html Which from what I found, are slightly modified Chinese $150 modules I believe from Class-D module manufacturer called Sangaway or something from memory. And these modules were also used in the far cheaper Red Dragon Class-D amps. https://www.reddragonaudio.com/products/s500 Cheers George |
Thx George.My only experiences are with Class A/B mostly and some Class A. I have heard tube amps but never owned one, and in past thought of Class D as mostly sub type amps (my ignorance). I started reading about the newer Class D amps and the price range is fairly broad. I also recognize pricing is not always linear with cost (whatever market will bring). But it is hard to see how 2 amps using the same identical amp board can vary in price so much which of course begs my question of why. If the cost of the parts, including cases, connections, etc. as well as the actual amplifier modules is a lot cheaper than their Class A/B counterparts, and their sound quality is close but it results in an overall cost reduction for the buyer than I would be more encouraged. It is difficult for me to hear much of this stuff without buying it. Not many nearby sellers. But I am probably missing something along the way. If the more expensive units are adding proprietary mods that would be one thing. Otherwise it starts sounding like a prettier case, etc. is adding a lot of cost! |
I do though see some advantages regarding heat generated (if that is a concern.. for me it isn’t) and size/weight. They offer a ton of power in a small mass versus trying to heft around a 90 pound Class A/B amp or an even heavier (with less power) tube amp. I see my system as something I want to get the very best from, and if I have to compromise and pay for it in less efficiency so be it. I wouldn’t buy a Ferrari put low octane fuel in it, stick cross-ply tires on it and drive it like a granny just so I could say I’m being kinder to the environment. But Class-D amps with the promises of higher switching frequencies technology in the future, may become all they need for me to jump camp, then my current amps will become door stops or boat anchors. Cheers George |
