Distortions,your hearing is excellent. What you are hearing is the best class D amps made to date that no one paid any attention to. The DS series amps from ARC. Lowish DF for natural bass (the DS225 is under 200) , no NFB, in house output, no OEM modules, huge linear PS. There is no other class D designed this way. I have owned over 10 class D amps over the years including one of the first pair of Veritas that Merrill produced. The ARC amps best them, the DS225 has a fleshed out midrange that competes with the best of class A plus all the desirable attributes of class D including low noise, low heat, high output.
The Future of Audio Amplification
I have recently paired an Audio Research DS225 Class D amplifier with an Audio Research tube preamplifier (SP8 mkii). I cannot believe how wonderful and lifelike my music sounds. The DS225 replaced an Audio Research SD135 Class AB amplifier. Perhaps the SD135 is just not as good as some of the better quality amps that are out there, but it got me thinking that amazingly wonderful sonance can be achieved with a tubed pre and Class D amp. I have a hunch that as more people experience this combination, it will likely catch on and become the future path of many, if not most audiophile systems. It is interesting that Audio Research has been at the forefront of this development.
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Hello all, as the topic of the Rowland Daemon superintegrated has come up on this thread, in the past, I wanted to give you a pointer to a review thread I have started for it. I was long hoping to evaluate the Rowland Daemon Superintegrated amp. Finally, a review unit was delivered on February 28th. I Started break-in the following day, and have been scribbling my listening notes since… The writing project will continue for at least a few months, until the integrated has stabilized, and I have exercised several of its many input and output options. I have been waiting for a long time for this 99Lbs single box critter. It is Jeff Rowland’s integrated flagship. The DAC + Preamp + 1500W/8 (2500W/4) dual-mono power amp in a single chassis is already sounding amazing after just a little more than a couple hundred hours of break-in.
Learning about Daemon is being a fascinating experience… join me to chat about it around its new Audiogon watering-hole:
And, feel free to PM me with any questions about it.
Saluti, Guido
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My class D ARC DS450 was a honey of an amp. Full of power, with an extremely tight and controlled sound. I completely appreciate the virtues of class D, especially having owned a quality class D myself. However, now that I have all tubes, with a REF 75se, even with a huge decrease in wattage, I am more satisfied with the sound. I can hear more emotion, less grain, and the sound soothes me. It’s a win win. I have no doubt that class D is the future, but after hearing all tubes, I’m willing to live in the past, at least until class D is perfected and gives the same goosebumps as tubes. |
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Along with Texas Instruments (TI), looks like Analog Devices is also getting into the manufacture of the GaN technology https://www.analog.com/en/applications/technology/gan.html Cheers George |
I'm happy to see this thread becoming more civil and moving toward the common good, that's awesome! This is such an important thread I was hoping this would happen. My part in this will be strictly listening and applying mechanics to the samples I receive. I have several amps in route to me now and several more being designed for me (Class D). In my listening so far I have found the same issue with Class D as I have with the other Classes, so for my listening I have removed the chassis. I am pro-fields not dampened fields. mg |
Yep looks like GaN technology has infiltrated into car audio also and beat the competitors, the SoundDigital SD300.2 https://ibb.co/80x8L1CCheers George |
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http://www.ti.com/power-management/gallium-nitride/overview.html Here we go one of the majors have got the rights to make it, watch Class-D take off now, and finally compete with the best of Linear amps in the mids and highs and beat it in the bass as it always did. Cheers George |
Reading a class D review (6moons/Nord Ice?) the reviewer mentioned power cord sensitivity as an issue. Several months ago I replaced a wireworld series 7 PC (MSRP $300) with a boutique $800 PC which sounded significantly richer And just a week ago I went from toslink to a prototype coax (not at liberty to say until production). Last night, listening to Ray Charles Duets was amazing Oh, my amp is Audio Alchemy DPA 1 |
Here’s a couple: https://www.researchgate.net/profile/Marco_Fanciulli/publication/224426167_Epitaxial_growth_of_zinc_... https://www.sciencedirect.com/science/article/pii/S0022024800008538 https://techxplore.com/news/2018-08-fujitsu-triples-output-power-gallium-nitride.html One thing that is difficult, and I have experience with series 2 and 6 elements to make CdSe-based nanocrystals with ZnS shells, is how to deal with crystal lattice mismatch; some elements’ bond lengths just don’t align well in order to interface optimally. Typically, one had to dope in some intermediary element to "fill" the gaps created by the lattice mismatch. Looks like there’s a similar challenge/constraint in fabricating thin layer GaN onto SiC wafers. This is why, IMO, we haven’t seen the industrial "breakthrough," yet. Ideally, one would want pure GaN crystals in the form similar to that achieved with SiC in order to make large enough wafers. |
GaN technology looks to be very promising and I read that the latest state of the art for power transistors in fast switching applications is to thin-layer GaN directly onto SiC substrates. This apparently saves big costs and allows the advantages of GaN to be realized relatively inexpensively. Looking forward to auditioning affordable Class D amps using this technology. |
It’s what I said, and have been saying now about GaN technology for close on a year. It’s the single biggest technology improvement step so far since Class-D technology made an appearance in "full range" audio, not just for subs. And what you said kinda echo’s that. "I definitely recommend people always seek out and consider the latest and greatest technical innovations that can clearly help move things forward" |
I definitely recommend people always seek out and consider the latest and greatest technical innovations that can clearly help move things forward, Class D or otherwise, especially before dropping big bucks on older technology alternatives that have not evolved much but now cost more than ever. Correct, all the current big $ or cheaper Class-D’s have not really progressed in a big way, yes they play around with different parameters, inputs ect and keep bringing out different "versions" of the same thing shifted sideways a little. But it’s still "basically" the same operation/componentry/topology as when it started. |
“One of the difficulties implementing the ICE module is its hungry demands for a powerful input signal. The 700 watt ICE module has low impedance (around 8KΩ) which, if not properly buffered, Little bit of obfuscation. A lot of Class D OEM modules have both buffered and unbuffered inputs. It is up to the manufacturer to either use the default, or build something else. This lets you do tweaky things like a tube input buffer, diamond, whatever. My point is, no end user is really ever going to feel or suffer from the low impedance inputs. Best, E |
Considering an ICE amp? I had this problem with ucore “One of the difficulties implementing the ICE module is its hungry demands for a powerful input signal. The 700 watt ICE module has low impedance (around 8KΩ) which, if not properly buffered, can cause plenty of poor sound from connected equipment. And what the designer uses to buffer it is critical. In our case, the Analog Cell handles not only this critical buffering task, but sets the synergy between the input and output. Another innovation employed in service of great performance can be found in the power supply design. Here, the Analog Cell received high quality DC through liberal use of regulation and power supply storage through use of capacitance multipliers and generous numbers of low ESR capacitors.” |
GaN, aside, I definitely recommend people always seek out and consider the latest and greatest technical innovations that can clearly help move things forward, Class D or otherwise, especially before dropping big bucks on older technology alternatives that have not evolved much but now cost more than ever. |
Great find, by mountainsong GaN technology for $4k, and this Technics SU-G30 is also a complete network integrated amplifier. Seems like it doesn’t use the 1.5mhz higher switching frequency that the $20k Technics SE-R1 uses, but does use a hybrid power supply, not all smp, and by just using the GaN technology it’s probably front of all it’s competitors anyway. https://img.usaudiomart.com/uploads/large/1837138-technics-sug30-network-amplifier.jpg What one reviewer thought BTW looking at the heatsinks in the SU-G30 above, that section is the GaN amp, it may have higher than todays 600khz switching because it’s using these heatsinks, as EPC said to me if left at 600khz there is no need for any heat sinking on any of the GaN boards, so it maybe higher. Could be a great sounding little amp, I can think maybe Quad ESL57’s would be nice as they can’t take to much wattage, or any > 90db speakers Cheers George |
Here's another press release, this time from
Murata Manufacturing Co's (subsidiaries P-Semi) Murata is one of the larger semiconductor manufactures and suppliers. https://www.psemi.com/newsroom/press-releases/545048-peregrine-s-new-fet-driver-brings-industry-s-fa... Cheers George |
This guy saw into the future of Class-D a couple of years ago using EPC's GaN technology. https://audiophilereview.com/cd-dac-digital/why-well-soon-be-living-in-a-class-d-world.html Cheers George |
Bit like D’Agostino, putting "Big Ben" on the front of his amps???? A Cadillac "Superfly" thing??? https://i1.wp.com/dirtyoldcars.com/wp-content/uploads/2017/07/Cadillac-1985-Eldorado-super-fly-1.jpg... Cheers George |
aolmrd1241 You can read more about it in these publication reviews http://agdproduction.com/news.html Yeah?? I don’t know about that one, jury’s still out, till we hear more about it. Looks to me like a bit of a furphy to gain an edge with the tube brigade, and cashing in on new technology. Might still sound great. I ask, why put solid state components inside an old 6550 vacuum tube envelope, bet it’s not vacuum’ed back out and sealed again either. Still it may sound good, just the whole gutted tube thing, stuffed with solid state, and still using all the tube pins as power/current transmitting contacts???? PS: OK he’s shown all his cards, in this statement " Company founder Alberto Guerra admitted that he did it largely for the sake of visual aesthetics. “Otherwise a class-D amp just looks like a box,” he said. The amp uses gallium nitride MOSFET output transistors, which Guerra says switch faster and allow the amp to have a noise floor in the -120 to -130dB range. Power is rated at 200W into 4 ohms." Good on him, I think it was a bad move to do it. (must have been an Italian brain snap to do the tube thing, they do make some of the best and worst cars also) Cheers George |
michaelgreenaudio That's ok Michael, here another little read you may be interested in, it from the AES Berlin White Paper presented by EPC's (GaN) Steve Colino and Alex Lidow inventor of the Power Mosfet all those years ago. EPC's White Paper "excerpt" on GaN technology used in the Technics SE-R1 and Merrill Element 118: "You can increase switching frequency and audio bandwidth to reduce the filtering cost. The choice in optimal switching frequency is always a trade-off in EMI profile, efficiency and audio performance. The ability to use much higher switching frequencies before compromising efficiency allows for a much range within which to make this trade-off. The result is a more optimized audio solution without fear of Thermal or EMI boundaries.This is why you'll see, Class-D's with heat sinks inside for each channel like the Technics SE-R1, if they've used the higher 1.5mhz switching speed available to them to use with the GaN. https://abm-website-assets.s3.amazonaws.com/ecnmag.com/s3fs-public/embedded_image/2018/02/figure1.PN... I also asked EPC by email what manufactures other than Technics and Merrill Audio are using or developing Class-D amp with their GaN technology, they replied today, other than the two I mentioned, they said: " We are unable to reveal due to the Non-Disclosure Agreement (NDA) with our customers.Finally it seems Class-D has stepped it up in a big way in technology because of EPC's GaN technology, and maybe put up a fight against the very best of linear amps for sound quality in the mids and highs, I think they already have that mantle for bass performance. Cheers George |
I find Brunos definitions kind of useless.Actually the use of a comparator has nothing to do with whether feedback is needed or not. If its a cheap comparator with offset problems feedback is probably a good idea, but IME the resulting amp will have the problems that many class D detractors (often, myself included) complain about. |
My best friend uses a Channel Islands Class D amp and he is comfortable using it. He would like to substitute one of my Class A/B voltage regulated amps which can control the bass of his demanding speakers instead but can't afford the change. He is a very discerning audiophile and part time remastering engineer (worked with Kevin Gray on some top quality LP remasterings over the years). So, he is satisfied for now with even the older technology Class D amp. I've mentioned that I heard the Prana Class D amp and it was musically involving and sounded very good. |
Thanks for the link George. Seems like I may be a little more picky than the folks mentioned on that thread. For me that is. As I have mentioned before I, first of all, don’t like the sound of amps crammed into over built chassis, they sound to constricted (congested) to me. I also don’t like the sound of huge transformers too close to the other parts hosting the signal. I don’t like the way heatsinks distort and the list goes on. In general I don’t enjoy big heavy amps, of any type. I also don’t like listening to crossovers or damped speakers or garden hose wire. What I do like is low mass and variably tunable products. Since I use my systems as musical instruments, including the environment, I can see where my views may differ from others here. I can also see where my views might fit into the future of amps more than some here. I really only have two beefs on this forum and neither has to do with what someone likes or believes. My two beefs are internet trolls and folks who talk about stuff they haven't actually done. mg |
Geez the guy who knows how to make good ones that have been successful likes them and the ones that don’t and make other stuff that must compete are not sold. What a shocker! Why is your name not in that article George? Oh and the guy who has done it successfully is only a "semi pro". I’m sure when you come out with your own Class D amp someday it will be the bees knees but threads like this might convince me to turn in my audiophile card sooner rather than later and I will surely miss out. |
George has sided with the lack of.Really??? And the only semi pro for it is Jeff Rowland, who makes them, wonder why?? https://audiophilestyle.com/forums/topic/31671-class-d-turns-out-it-does-suck/?do=findComment&co... |
assuming the are the same George who reviewed the Hattor passive pre with a NordSorry you need to do your homework there sunshine, you've got the wrong George I'm afraid on that one. No one said it was garbage, I said it doesn't compete with hiend linear amps "yet"!!, one day it will with the likes of the Technics SE-R1 and the Merrill Element 118 now using the new GaN technology that it needs to be rid of it's achilles heel to get there. Cheers George |
Seems to me, in most of the class D threads I have read, there are more positive reads than naysayers. I'm fine with it if you don't like class D for whatever reasons, just don't tell me it is garbage and has no place in HEA! Reading between the lines, it seems many of the naysayers have NEVER had a class D amp in their systems. I said "many" not all.... |
Eric you've tried numerous threads to get this Class-D "praising thing" on a roll, never to keep going, because of the "non acceptance" by way too many for you to counter. It's the other way, George. Every time anyone says they like Class D you jump in with as many posts as you can explaining why they must be wrong, but (based on zero evidence) the next big thing will surely fix it! I think an objective read of my posts, whether about Class D or other will show which of us has a point to prove, and trouble making it. Best, E |
Eric you've tried numerous threads to get this Class-D "praising thing" on a roll, never to keep going, because of the "non acceptance" by way too many for you to counter. Give it up be happy with yours, that you say you can't hear any problems with it. And let those that can, and have been down that path go the way they want. The only ones that are really backing you, are manufacturers that are making, going to make, or selling them in retail supply, they all have a monitory interest in doing so. It almost sounds like sometimes you asking for acceptance for owning Class-D and listening to it. I've always said Class-D will be the top dog one day, just not yet, all the detractors (designers and audiophiles) of it have the same common complaint, it's the upper/mids and highs that are the problem, never the bass, this is a done deal showing where it needs to improve. |