@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.
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!
876 responses Add your response
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! |
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 |
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 |
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 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. |
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. |
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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 |
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 |
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? |
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, |
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 |
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! |
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! |
@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... |
Hi Doctor_lipp! Yeah, I use it on my subwoofer along with bass traps and other room panels. It is essential for the last two octaves. 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. Still, proof is in the listening. Best, E |
@erik_squires wrote: One really interesting thing about the Technics however is the heavy DSP processing they rely on to flatten the electrical amplitude and phase response. I'm tempted to do this with a miniDSP to see if I hear any benefits.I have been using a miniDSP nanoDIGI (stereo digital in, quad stereo digital out) to equalize and bi-amp / tri-amp. Its very flexible. Using it I was finally able to tame the wild bass modes in my listening room. Get one, you won't regret it :-) |
mains167 posts04-15-2017 4:52amNord One SE uses the same components as the Nord One UP, Hypex NCore NC500, twin SMPS1200A700 PSU’s in our beautiful sleek Japanese Mono Block or Stereo Chassis. SE comes with Nord Class A Discrete Input Buffer board with choice of discrete Op Amps, Sparkos SS3602 or Sonic Imagery 994 +£30 and Sparkos discrete Voltage Regulators. Choice of Dual Mono Stereo or Mono Block chassis Do you compare to Bel Canto Ref600 also ??? Bye |
As I mentioned before I have a Primare I32 and a Topping TP30 mk2 that I connect to the tape out to drive a Stax headphone system. I have a pair of old BA T-830s connected to the Stax adaptor for the hell of it. Sometimes, when I want the best sound from the Stax, I connect them directly to the Primare, which I did tonight. After a while I reconnected my 'big' speakers, Canton Ergos, to the Primare and popped I Robot SACD into the BDP-95. It sounded really good. I got to a loud passage and turned the volume down with the remote. Still too loud, so I turned it down some more. And more, and.. I finally put my glasses on and saw that the Primare was down to 0 volume and I'd left the TP30 on. I had been listening to the BA T-830s being driven by a 10 Watt (generous) class T amp the size of a sandwich in a 38'x28' room with the volume less than half way up and it was still too loud! |
NAD D 3020 sound quality This is a good performer, a huge step up fro my $20 Lepai 10W/ch digital amplifier. It is extremely quiet and smooth, without grain or harshness but also without warmth. The bass boost is a huge help as my desktop speakers are pretty lean sounding. My previous experience with NAD DACs was pretty negative, but this is pretty easy to listen to. Tons of air and detail. But zero warmth. In this sense it kind of goes towards the Emotiva/Asian processor sound qualities. Kind-of, but not nearly as bad as the worst of them. There's just no sweetness or warmth at all in the sound quality. "Stark" may be a good way to describe it, but without the thin/limited range effects I get from the worst of the Asian designs. Reminds me a lot of the 1990's digital sound, if you took that and cleaned it up a lot. So, killer, top of the pack? No. Quite enjoyable, space saving and feature packed is how I would put it. Best, Erik |
Found a partial answer: NAD calls the D 3020 a "hybrid digital amplifier," by which they mean that not all of its circuitry is in the digital domain. The D 3020 combines a Cirrus Logic DAC (eight channels mixed down to two) with a class-D output stage designed by Hypex, of the Netherlands. According to NAD, the output stages aren’t fazed by low-impedance speakers. Hard to interpret exactly which part is which though, especially since Bruno Putzeys bristles if you call his amps "digital." Still, I will guess this is at least not a Hybrid a'la nuForce or Yamaha EEEngine, but something else. https://www.stereophile.com/content/nad-d-3020-integrated-amplifier-sam-tellig#1FLoXpsCMuhoTAk1.99 |
My goal was a little desktop integrated or pre/amp combo. After hemming and hawing and fretting I purchased an NAD D 3020. My local dealer had one $100 off. I ruled out all of the Parasound Z series just because they are too big. at 9" wide they wouldn't fit on top of a speaker, like I need. Plenty of digital and a couple of analog inputs make the input selection pretty good. There is also a bass boost which is perfect for my little desktop speakers. So far so good. The one negative is really the volume display is hokey as hell, and it takes a lot of turns to adjust it. The display has a series of numbers: -20, 40, -60, -80 and -100. As you turn the volume down the numbers dim, or go off. The physically larger sibling the 7050 has a graphical display with direct volume readings in dB. It was only a little more expensive, but seemed to lack analog inputs and was twice the physical size. They call this a hybrid digital, but I could not find much information on what makes it a hybrid. My only source right now is the PC, via analog, but I'm always careful to get motherboards with S/PDIF outputs so I'll try that eventually. |
Very nice to see almarg and atmasphere team-up, step up and use their knowledge/experience to solve islandmandan's noise problem. Nice job guys! What I've consistently noticed from listening to good class D amps in my system, from my initial Class D Audio SDS-440-CS stereo amp to my Emerald Physics 100.2 to my most recently purchased D-Sonic M-600 mono-block amps, is their exceptional quietness; music seems to emerge with more impact due to the dead quiet background. I believe this silent quality is also a primary contributor to the other obvious characteristic of good class D amps: a very detailed presentation.. I'm almost certain these class D attributes will now be very evident to islandman now that his amps are operating in their typically silent manner. Enjoy, Tim |
Hello Al, Ralph, all, I disconnected the inputs on my stereo dual module Class D amp last night, and the right channel was silent. Inexplicably, the left channel was still noisy. Today, I rounded up some spare I/C's that were long enough to reach between the preamp/processor and the amp, disconnected the leads from the pre-pro to the separate tube preamp, and connected the amp directly to the pre-pro. The two channel and three channel Class D Audio amps are now quiet as a tomb. From here on out, all my HT and multi-channel listening will be through the Class D amps, and two channel listening will be through the SET 300B and Transcedent Sound Grounded Grid preamp. So your idea of the problem being input-related was spot-on. I also found I had my surround speakers connected to the rear surrounds on the pre-pro, which may have been causing some of the problems as well. So, everything is working much better now, though I will be limited in my use of the Class D amp. I will have to re-think my connections to see how I can better utilize the Class D stereo amp, but at least for now, mission accomplished in attaining blessedly silent noise-free listening. For that, I can't thank you men enough. Having your input on this forum is a true blessing! Regards, Dan |
Thank you Al, Ralph, for your always valuable input. I will re-insert the Class D amp into the system (I was taking time off from the noise, and very much enjoying the SET 300B in the system), and try what you have suggested. I'm wondering why, though, a single module, in stereo mode, is quiet, but a dual module/single power supply with both modules set to bridged mode is so darned noisy? Thanks, Dan |
Thanks for the additional info, Dan. But if I understand correctly it still leaves open the possibility that the DVR or its remote may be the source of the noise, as it would seem conceivable that the class D amps may simply be more sensitive to pickup of electrical noise that is present in their environment than the SET amp. Perhaps as a result of wider bandwidth, or differences in gain (which is typically higher for class D amps than for SET amps), or any of the many other differences that may exist between the two designs. Obviously what I was speculating is a somewhat wild guess, but it was prompted by your mention of the effects of the DVR’s remote. Best regards, -- Al |
Hello Al, To shed a bit more light on the subject, and I don't know in what way it may effect your idea of the issue, but when the Class amp is out of service, and my SET 300 B amp is in use, there is no issue with noise. Even when my HT system is in use with the SET amp (I use a separate tube preamp that the front two channels are connected to, including having the processor stereo cables run to the two channel preamplifier). So, my thinking is the noise emanates from the Class D amp, not from the cable box or processor. Thanks again regards, Dan |
...when my home theater setup is on (Comcast DVR, Primare SP 31 HT processor, Sony HDL display), when making changes on the Comcast remote, the noise abates momentarily during the sequence of time the button is being pushed.Hi Dan, That’s certainly an interesting finding. Perhaps the DVR is the root cause of the noise, possibly even when it is turned off and most (but presumably not all) of its circuitry is unpowered. If you already haven’t, you might try disconnecting it and pulling the plug on it. Also, does the remote communicate with it optically, or via RF? If the latter, you might try removing its batteries. Best regards, -- Al |
Hello Ralph, The noise is a bit difficult to describe. It's similar to a 60 cycle hum, with a sort of "buzz" in addition to the hum. Strangely, when my home theater setup is on (Comcast DVR, Primare SP 31 HT processor, Sony HDL display), when making changes on the Comcast remote, the noise abates momentarily during the sequence of time the button is being pushed. I know this sounds far-fetched, but it happens. Erik, Ralph, I appreciate your responses, thank you. Regards, Dan |
Hi Dan, I don't know enough about your amps to help you I am afraid. The DIYAudio web site is a great resource for kits and components. The site is down for upgrading, but should be back up by Monday, July 10, 2017. I would ask there. While some digital amps have noise issues when you put modules too close together, I would not think this was an issue. I would suggest try unplugging all but 1 module, and see if that does anything to the sound quality. If so I wonder if your issue is proximity. Best, E |
