Have you tried reporting my post to moderation?
No need to, because I see it has been removed, as admin must have read into your twisted response, and self shilling agenda. They're not stupid and know it's impossible to create a "retail product" complete Class-D board, using all smd components, making it by hand soldering. You say it can be done, but that would only be a 1 off prototype and not the production version.
I think you will find that the post stands because I've made no personal attack
Tweak didn't think so as he responded to your comment, which should also be removed, but then he's just your lackey . |
Who said production boards will be soldered by hand?I didn't I didn't, I inferred if you design a GaN board from scratch, you'd do the whole thing SMD because the GaN semiconductors are all SMD, therefore my statement was. "
They're not stupid and know it's impossible to create a "retail product" complete Class-D board, using all smd components, and making it by hand soldering" |
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You know exactly what I'm talking about and twisting it once again, still shilling for your self and abusing any opposition. Stay with tubes sunshine, you'll be better off. |
George, as I said in a previous post, you recently posted a list of manufactures poo pooing class D. I said it was because they see it as a threat to their non class D amps...... Which is exactly what you just said. Just look at the calibre of those manufacturers v the ones trying to bring out backyard Class-D’s on these forums You think RicEVS is ’stuck’ selling only modified IcePower class D? Why would you think he is not able to switch to GaN To do that you need to buy either ready made boards then do simple mod and call them your own, if not and you want to do your own GaN Technology boards, you need the knowledge to design it from scratch, and you need some serious automated wave soldering machines to do all those smd parts that are involved, you can’t do it by hand. http://www.onlysmt.com/Uploads/5b7bf3e74d93c.jpg |
There you go twisting things again.
The only interest you Ricevs and
Mike Mivera have coincidently in degrading anything to do with Class-D GaN Technology, is because it poses a big threat to all your yet to be released non GaN class-D amps. Which you all so delicately push here on these threads, except for Mike who got what seems to be a permanent sabbatical away from Agon for pushing too hard.
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That sine wave is at the switching frequency of the amplifier; if you are saying you can hear 250KHz or 1.2MHz sine wave good luck trying convince anyone that you aren’t a nutbag. Your twisting things to suite your self, I never ever said that you can hear these frequencies, I’ve always stated they have an effect and the "output filters used" in all Class-D amp to remove them have an audible effect, because they cause problems!!, and if the "output filters" are shifted up higher because the switching frequency is higher, then problems become minimized. As for you getting abusive, I understand you are trying to promote and protect your upcoming new non GaN Class-D, because all linear amps tube and SS will go the way of the dinosaur once the new Class-D GaN technology takes hold. |
George,
What amps have you removed the output filters from so you can test your "idea"? Your kidding, your tweeters wouldn't last a nano second, if you didn't know??. What we have here creeping up are manufacturers using the threads to promote their new Class-D products, it’s not on guys, there was one removed/banned totally from Audiogon not so long ago, take heed. |
Keep plugging away Eric, you live with a technology that has been flawed since it’s inception.
GaN technology will finally get rid of these flaws of dead time and switching noise.
No one here knew what GaN was till I posted up about it’s development at EPC years ago, before the Technics SE-R1 was released, I said then it was coming for Class-D and it would finally take Class-D up into the hiend for being for midfi and sub use.
I suggest all to wait till this comes about and enjoy your linear amps till then, otherwise you’ll buy into a Class-D technology that will be very hard to sell, once GaN has taken hold in Class-D in an affordable way.
Cheers George
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BTW 'switching noise' really isn't a thing unless the switching frequency is really low,
Which it's artifacts are, even the non technical can see it in any Class-D's 1 or 10khz square wave from on the amps outputs, and in the phase shift the filter produces down to 4khz in many cases.
I know your bringing out your own Class-D amps just like Ricevs is also using off the shelf boards (maybe slightly modded) that's maybe why the negatives toward the GaN Technology, that now even Texas Instruments are behind.
https://e2e.ti.com/blogs_/b/powerhouse/archive/2018/06/26/the-sound-of-gan
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I enjoy it immensely, actually Good for you, the majority in hiend don’t, that will change with GaN Technology and that’s fact. |
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I’ll say something positive about class D, and wait for George to say something negative about class D", thread.
Seeing you mentioned me,that's where your wrong and deluded, and non technical. . I only have about the old Class-D technology, not the new GaN Class-D, which I have nothing but praise for "if" used to it's fullest. Simply put for you, because it, (GaN) removes the old technologies achilles heels x 2 (dead time and switching noise), x1 (dead time) if not used to it's fullest, as some have done. |
Maybe I missed something? More likely don’t understand. I believe this is what Georgehifi is also referring to in his comments. Especially in the upper mids/highs golfnuttz, 100 times? you tend to over exaggerate and are a bit misinformed; That would be you, not golfnuttz as many others hear it also, and it just "happens to be" where passed/present day Class-D technology has it’s achilles heels, in dead time and switching frequency issues, and GaN Class-D Technology if used for all it’s worth fixes both these issues, as presented to you from the inventors, (EPC), the manufacturers TI (Texas Instruments) and Technics with the SE-R1 and to a degree the SU-G30 (dead time not higher switching frequency). |
@georgehifi, I stand corrected, you are correct. For whatever reason I was under the impression that it was a class D amp. It is not. Well that's ok, but now I'm really curious about class D, George Hifi you got a loaner I can try?
Sure a couple you can choose from, you can pick up (i won't post) from North Manly 2100 Sydney, where are you coming from. Cheers George |
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A tidbit for the anti D crowd, recently a friend who has been out of town came by for a visit. We used to jam quite a bit and he did not know my Krell Kav 250 died and is temporarily replaced by an Emotiva Gen3. While jamming he exclaimed that my sound was the best he’s heard yet. Go figure. He still don’t know it’s class D. All his amps, yes multiples, are class AB and sound fantastic. Sorry to burst your bubble gillatgh, I maybe wrong, but for memory I think you’ll find all the Gen 3 Emotiva’s amp are linear Class-A/B driven from Class-H power supplies. They make a cheap $300 budget Class-D called the PA1, PA standing most likely for "Public Address" amp. Cheers George |
I believe that a lot of the negative criticism that comes with class D amps is from people who already have a preconceived opinion of class D which convinces their brain that it’s not good before they even give it a chance. Tell that to these brain trust guys, it’s the same technology now as it was then, may have moved sideways a little, but still basically the same. Cyrill Hammer of (Souloution Audio knows very well about the Class-D’s achilles heel, and says so, which GaN can fix, and why you few doubters should embrace it, instead of putting **** on it The only one to give it any credence is Jeff Rowland, I wonder why? does his company make Class-D?? yes it does
Bob Carver
"I built many of them right here in my own laboratory with the thought they could and would fulfill that final promise.... I was never able to build a Class D amplifier that sounded as good as a linear one."
John Curl (Parasound, CTC, Vendetta Research, Constellation)
"Some version of hybrid Class A/D looks like the future in optimum audio design."
Cyrill Hammer (Souloution)
"if you want to have your product performing at the cutting edge it is not possible with today’s known switching technologies. In order to come close to the performance of the best linear design we would need high-current semiconductors that provide switching frequencies of several MHz or even GHz."
Lew Johnson (Conrad Johnson)
"I tend to think that Class D circuit design is an approach best relegated to producing low-cost, physically manageable multichannel amplifiers—where one might accept some compromise in sound quality for the sake of squeezing five, six, or seven 100 watt channels into one moderate-sized package for a budget home-theater installation."
Vladimir Shushurin (Lamm)
"No, it is not. And I would like to respond to the second part of this question with an allegory. Any field of human activity defines a number of requirements which, when properly implemented, guarantee a positive outcome.
For example, the basic requirement in the army and sports is an able-bodied individual. So, it would be quite natural to concentrate on searching for such an individual (especially as we know where to find him).
However, out of the blue we decide to choose a feeble-bodied person who, on top of that, is encumbered by various diseases. Having made this decision (which is a priori improper) we start justifying it to ourselves and others by citing the great state of our medicine, which is capable of curing many ailments."
Fumio Ohashi (BAlabo)
"No. Class D can’t really be considered for super-high-end performance in its present stage of development, although it can be fine for mid-market products."
Nelson Pass (Threshold, Passlabs)
"Does a $10 bottle of wine compete with a $100 bottle? Of course it does, and it often wins based on price. Right at the moment Class D designers seem to be still focusing on the objectively measured performance of their amplifiers. I expect that at some point the economics of the marketplace will encourage them to pay more attention to the subjective qualities, and then they will probably play a greater role in the high end."
Jürgen Reiss (MBL)
"I have worked a lot lately with Class D. Ninety-nine percent of Class D circuits are not competitive with linear circuits.
Most Class D sounds sterile. It’s tricky to figure out what to do to compensate for that."
Jeff Rowland
"I consider Class D to be highly competitive in the present, and to offer an evolutionary pathway of audio design that may produce even more astonishing results in the future."
Thorsten Loesch
"I have yet to hear a pure class D Amp I’d rate above "below average for solid state" (which is not very high performance).
In a little update of my classic "Valve Analogue Stages for DAC’s #" I wrote:
"Perhaps more crucially, so called Class D Amplifiers, which have in recent times sprouted up like mushrooms after a warm rain, continue to use the straight two or three level modulation scheme described above. And thus they still require the use of heavy handed noise shaping to attain anything like acceptable 16 Bit Audio performance.
The clock frequencies for these amplifiers are usually at 300 KHz to 1MHz in the best cases. That is 3,000 to 10,000 times lower than what is required to attain 16 Bit / 44.1 KHz performance without noise shaping and
other forms of signal manipulation!
And again, one is baffled and perplexed by the rave reviews many Class D amplifiers receive, as baffled as one was about the late 90’s reviews of timeslicing dac’s. The best of breed I have auditioned were certainly not bad; however in direct comparison to the best available valve and solid state amplifiers they do not produce a very good sound. Well, at least they offer novelty and the reviewers something to write about other than another (however good sounding) 8 Watt valve amp.
Incidentally, the best sounding Class D amps tend to be really low power single chip devices (putting out little more than the 8 watt valve amps), presumably because they are faster AND because they always work near what one might call “full scaleâ€, if they would be dac’s. On second thought, they of COURSE are DA Converters and where a Class D amplifier accepts analogue input directly it is an A2D converter followed by a power D2A converter!
What an insight!?"
Mark Levinsons interleaving of multiple Class D Amplifiers is potentially a step in the right direction, but does not go far enough.
Personally I think that the best option would be something that combines a Class D Amplifier for the heavy lifting with something Class A for fine detail. Probably implemented in the style I did for AMR’s AM-77 "Jikoda$" Style. In this case both of the circuits involved can operate fully open loop.
In many ways the problems in Class D Amplifiers are analogous (but not identical to) those in Class B Amplifiers (but without an option to implement Class AB or Class A) so similar solutions apply.
All Class D amplifiers are essentially delta-sigma DAC’s.
If the input is not digital PWM signals (aka "DSD") but analogue audio then it is also a Delta Sigma Analogue to digital converter...
Now DSD (aka SACD) which to my ears fails to come close, never mind equal true PCM CD Replay in most aspects of sound quality, operates at 2.8MHz switching, or around 10 times as fast as common Class D Amplifiers...
Why anyone would want to listen through an A2D followed by an D2A Converter that are around 10 times worse than single speed DSD is beyond me.
But with enough hype and snazzy naming it cannot help but sell high and wide.
Cheers George |
This is what I mean about George doing very little listening, and therefore making it hard for his arguments to be persuasive. You and your mate tweak give/present nothing technical in your posts to why using old present Class-D technology is as good as the new GaN technology, all you guys can do is attack on a personal level. If I can’t say "I like Class D" An I’m not saying you don’t like your Class-D, as your many threads you have started on it state. Just look at what the new GaN technology will bring to it, and fix it’s achilles heel it has in it at present, that you obviously can’t hear but others do, "dead time" and "switching noise frequency" |
ricevs
I have no doubt GaNs will be used in state of the art products some day There will be State of the Art GaN and other super class D amps in the future....the future looks bright. +1. I finally agree with something you’ve said, could it be you've seen the |
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You are dreaming, at best Class-D has a 40-50% share over linear, and that’s mainly for low to mid fi and subs, in the hi end it favors linear tube and solid state much more.
And you and your mate tweak have your heads buried in the sand, if you can’t see the advantages of GaN technology used in Class-D over past/present technology.
Guarantee you’ll be one of the first in line to get a GaN one when they meet your price expectation. Why not embrace it, you can’t stop it from coming that’s for sure.
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While it’s true that the tubes do nothing, they are pure marketing genius. People that get sucked in buy this "pure marketing genius" are what I call a "glitz queen" and this is the reason he has a $15k odd price tag on them. When what’s inside amounts to a few hundred dollars. How could he then charge $15k odd for a small grey box. It’s not marketing genius, this is feeding on the gullible. Even he said in an interview, it’s bulls**t, and just there to amuse the tube freaks. |
You are vastly outnumbered, Supertramp Eric their song was written for you. You are dreaming, at best Class-D has a 40-50% share over linear, and that’s mainly for low to mid fi and subs, in the hi end it favors linear much more |
mapman Yes TI appears to have GaN based Class D modules now and can’t imagine those cost much more than their others. Anyone know of amps that use these? Thanks for that info. Didn’t think it would be long before big companies like TI (Texas Instruments) got into GaN for audio use, others like Motorola ect will follow Here is a snippet from TI’s propaganda on the GaN technology. "GaN FETs provide superior switching characteristics, which enable even higher efficiency, better thermal sinking reduced size and weight, as well as reduced distortion for Class-D audio solutions.
GaN’s inherent characteristics provide a more ideal model of a small-signal PWM, driving the output filter. Along with this, the absence of a body diode eliminates reverse-recovery charge, which enables increased output linearity. Both characteristics allow GaN to minimize THD and ultimately create higher-quality sound." Cheers George
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And that’s where a lot of anti-Class D bias looses all of its wind.
And in your forceful statement with the heading to this thread
"I went from Class D to Luxman A/AB - And most of what you think is wrong" means what most of us who feel Class-D has problems in the mid/highs, think what we're hearing is wrong!!!! Good luck with that one Eric. |
Hum class D....should I sell my 300B??? Not unless you have quite a few $K for the latest GaN ones at this time, still I would think is the Technics SE-R1. As they have fully utilised the higher switching speeds GaN technology has to offer. From Audiophile Review. In fact, that transistor technology is available today and is increasingly being used by manufacturers to create near perfect sound quality for Class D audio systems.
The greater switching speed of Efficient Power Conversion’s (EPC’s) eGaN® FETs allow amplifier designers to increase PWM switching frequencies, reduce dead-time, and drastically reduce feedback; in turn, producing a sound quality previously limited to large, complex, heavy Class A amplifier systems.
A high-definition eGaN FET-based system with higher PWM switching frequency, reduced feedback, and higher bandwidth produces the sound that has the warmth and sonic quality that audiophiles demand; while actually improving upon the power efficiency of traditional Class D.
There's your lovely 300B sound, + some more. Cheers George |
@georgehifi, I can only take your opinions about GaN seriously I don’t really don’t care, what I post is for others to read, from people far more knowledgeable than you, as you just push what you sell. |
would say that’s a 10/4 good buddy............
I have been enjoying my new Merrill Audio Veritas mono-bloc amps for the last month or so. These amps have been a revelation in my system
You should have a listen to the Merrill Element 118,116 or 114's from reports I'm getting from reviewer friends that do show reports, they are even more of a revelation, than the older Veritas. GaN Technology is definitely the future for Class-D, if fact even in linear amps can benefit a little also (but there's no switching speed advantage there), it more the other benefits GaN technology can give. Cheers George |
But only George can hear it. Not just me sunshine, everyone else that hears something wrong in the upper mids/highs with Class-D, you just don’t hear it, and choose to ignore that very big fact. https://live.staticflickr.com/3666/33726831296_436f60f683_b.jpgYou say you can’t hear it that’s fine then live with it, but stop starting new Class-D threads to look for confirmation/cred from everyone about how good it is compared to the best linear amps. When that old Class-D technology moves forward instead of sideways with the new GaN technology and make use of the 3 x higher switching speeds available, then it will compete with the best linear amps. I’ve said it before, when Class-D can finally drive a pair of speakers like my big ML’s, Wilson Alexia, Alexandria or Watt/Puppies to their very best like linear amps can, then it will be time to sell my inefficient boat anchors, to purchase them. |
So, @georgehifi you have compared GaN with other class D amps? Once again in case you missed it, or just inconspicuously
trying to shill your own wares - Don’t need to, they are all variations on a technology that has an achilles heel that can’t be fixed.
- Even Mark levinson tried to get around the problem with these massive monoblocks with very robust "higher order" output filters to get rid of the switching noise as to not effect the phase shift into the audio band, but it flopped also. https://ibb.co/YdVr6Wr
- The only way is much higher switching frequency with low order filters that are also set much higher, aka Technics SE-R1 because of the GaN technology.
Cheers George |
@georgehifi please try class D amps by SPEC, Audio-Nec and Mola Mola before commenting further.
Don't need to, they are all variations on a technology that has an achilles heel that can't be fixed. Even Mark levinson tried to get around the problem with these massive monoblocks with very robust "higher order" output filters to get rid of the switching noise as to not effect the phase shift into the audio band, but it flopped also. https://ibb.co/YdVr6WrThe only way is much higher switching frequency with low order filters that are also set much higher, aka Technics SE-R1 because of the GaN technology. Cheers George |
@georgehifi what class D amps have you heard? Many as I’m in the industrie, the only one that impressed so far has been the BelCanto 600M’s, but only when they drove a very expensive two way, that had a very benign 6ohm load in the upper mid highs, because they used I believe the top Raven ribbon tweeter. The same amp let me down severely, when it tried to drive my highly modded ML Monoliths which has the latest same as the Neolith panels. Cheers George |
Look at what you posted, you started the personal slurs again Iric with your post, not me. " I was really worried that Goerge would have gotten too old and tired not to raise the same tired and irrelevant tropes"
So just suck it up sunshine without the slurs that start these confrontations. And come back with some thing technical or useful against what I’ve posted, not just a derogatory slur, your getting good at those, if you've got nothing then don't say anything. |
same tired and irrelevant tropes
Only in your own mind Erik, as you continue to start Class-D posts to get others validate your Class-D views and purchases because you can't yourself. |
This example suggests that it is far better to form opinion after listening to particular amp than making blank statements about whole class D. Measurements don’t lie, there is considerable phase shifts down to 5khz if the output filter is set too low to minimise switching frequency being too high in amplitude. And if the filter is set too high the the switching frequency become very apparent riding on the back of 1k square waves. (re: the links I posted above) The only remedy is to raise the switching frequency by at least 3-4 x and set the fiter much higher so it can do it’s job, as Technics has done to 1.5mHz with the SE-R1. And this can be done using GaN Technology. From EPC’s Steve Collino, past inventors of the Power Mosfet and now the new GaN Technology. "Our GaN FET will give an even higher performance difference compared with MOSFETs in both sound quality and efficiency at 1.536 MHz." He said then, they have to be heaksinked, as Technics had to do. Cheers George |
Erik instead of burying your head in the sand about the problems that Class-D has had since it’s inception, with switching frequencies+filters, embrace instead the new GaN technology, that when used correctly as Technics has done with the SE-R1 can address those problems forever. At the expense of a little bit of heatsinking.
This then will put Class-D up with the best linear amps into the very hiend, instead of half of the audiophile not accepting it at all, because they hear things in the mids and highs you obviously can’t.
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my old class D amp had 60kHz bandwidth Yeah and it probably looked like this on a 1khz square wave https://cdn.head-fi.org/a/2780785.jpgIt all about how much switching noise is let through without causing phase shifts down into the audible range. And that why 1.5mHz is good for switching frequency, because it can be filtered out well above and not have any phase shifts down into the audible frequency band, like all the others do. Here is the Anthem Statement M1 claimed frequency response to 45khz look at it’s square wave, not pretty, in fact if you saw this on a linear amp you’d have to say it’s broken. https://www.stereophile.com/images/1212AM1fig02.jpgCheers George |
That’s true, but it might open another bag of worms. In current designs filter leaves about 1% of switching noise on the speaker cable. As you say "it might" You’ll just have to look at what Technics did on the SE-R1, no complaints about it becoming an RF transmitter using normal non shielded speaker cable, just praise for it's good sound. Maybe they’ve done some fancy RF output filter as you can see (orange) the amplitude and cycles of ringing are much reduced as well the square wave itself is far better. https://ibb.co/MpmqzGtCheers George |
I believe after a trusted friends opinion on how the Technics SE-R1 sounded, that you may as well stay with what's used now with the old Mosfet technology and 600k switching speed, if the GaN's higher switching speed transistors are used WITHOUT utilizing it's higher 1.5mHz switching speeds and filtering that their capable of.
It would be a waist sonically to use them and not fully utilize their performance advantages.
(Bit like never going over 2000 revs in a Ferrari)
Cheers George
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For example, I’ve read that GaN transistors are capable of switching so fast they literally eliminate dead-time and any resulting distortion caused by it. I would imagine that any good amp designer would believe that substituting these for the typical FETs used would result in significant improvements in the sound quality of any class D amps, or really any solid-state amps, that they’re utilized in. This is so correct, but so far it seems that only one has utilized this ability to take the higher switching speed up to 1.5mHz available with GaN (2.5 x higher than present), and that is Technics with their SE-R1, it does mean they had to use heatsinks to get it. Also it’s not that the higher switching speed alone make for the good sound it gets, it’s also that the "low order output switching noise filter" that all Class-D’s have to use, can now also be taken up 2.5 x higher, this then has no effects now down into the audible range, like the filters today do, which can cause phase shifts down to 5khz, and why many complain about something not right in the upper mids/highs. Cheers George |
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Armed with this knowledge it might be interesting to ask a manufacturer of a GaN-based class D amp why their amp is so much more expensive. You’d have you been asleep, that goes with any new ground breaking technology eg:TV’s The first models in audio by the boutique manufacturers are always sky high priced because they make their own boards, then once that new technology has proven itself to be the future, those pesky people in Asia like get hold of it and design and manufacture complete boards in the millions for a $100 dollars, that’s when the smaller manufacturers get them and charge too much because they put them in glitzy chassis and charge a fortune and rest on their past names. soundsrealaudio....."Hum class D....should I sell my 300B???"
This guy thinks so!!!
https://www.youtube.com/watch?v=VMc7Y1RYiwE Yes expensive also but they are the new GaN Class-D technology, stuffed inside a stupid tube housing, to keep the tube guys happy. Cheers George |
@georgehifi wow that’s pretty crazy, looks virtually identical! yep! try to pick the odd man out. It all comes from the same factory in China. Cheers George |
