So, what class D amps have you heard and which Class A transistor amp did the AGD better and in what ways? Thanks.
Class D amps that are superior to all or most?
Recently, I have heard about some Class D amps that may be close to the best there is regardless of class. Certainly, this technology has been in development for decades. The main issue has always been the switching power supply. In this regard, I have taken notice of AGD. They have created a whole new power supply that “switches” at a frequency 100 times the normal silicon based MOSFET. The designer uses a gallium nitride based PS. Interesting, it is enclosed in the KT88 glass envelope that sits on top of his amps. I am aware of two more pricey amps that seem to be also at the top- the Solution and the Merrill. There must be others that compete for the title. After my thread, “Is there a SS amp that can satisfy a SET guy?”, I am still on the quest.
Don’t want to spend $50K!
Don’t want to spend $50K!
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Over the decades, I owned numerous class Ds several from W4S, then Emerald Physics 100.2SEs with custom fuses, then Audio Alchemy DPA -1, PS Audio M700s, and for ~ 1.5 years (long before PS Audio introduced the M1200s), I have owned a EVS 1200. At the time I bought it (30 day trial) I was anticipating getting a LSA Voyager GaN amp to compare. Well, shipping has still been delayed (though now supposedly shipping by the end of this month MSRP $3000; May 2021), much of the delay with CoV, not being able to get parts from china and numerous issues discovered when firing up the earlier mules, so... It has been reported that several of the available uber expensive GaN amps sound overly warm, which for me is no bueno! How does the Audion stack up, I will likely never know What I can say is the Voyager has its work cut out for it as the EVS 1200 stands tall, very tall indeed. Of late there are 3 reviews of the PSA M1200s (MSRP $6000) all extremely positive, and all missing out on EVS’s amazing pixie dust. But ric is no longer making them (or is he?), and the 200/400wpc Voyager has a very attractive MSRP |
Yesterday
my EVS 1200 just got way more holographic. When I operate my oppo 105 direct, it bypasses the Audio Alchemy DDP-1 dac. I have been thinking about reconnecting my optical cable for a long time, but figured doing so would negate my ability to play SACDs (yet to be determined), but did so yesterday. I have to research which cable I have, it's red and likely a low end Wire World, but DAMN. Almost too rich but definitely the music is more out into the room hth |
The Mola Mola Integrated is excellent, Mola Mola and AGD are at the top of class D. I own the AGD amps and plan on buying the Mola Mola DAC as i like the AGD amps over the Mola Mola amps but the Mola Mola DAC is the best DAC i have ever heard. Mola Mola and AGD products have to be heard, they tower over any of the other amps mentioned here by a big margin. Go listen and you will understand. |
douglas_schroeder The revelation you had with the Legacy Audio i.V4 is exactly the same i had with the AGD Audion mono block amps. It's a powerful word but stunning fits my experience. And not just for class D but for any class of amps, the AGD's can go up against any amp. It's a wonderful time to be an audiophile. |
There's also a 2-channel version. https://destinationhifi.com/products/legacy-audio-i-v2-stereo-amplifier?variant=31916144525452 Coda used to make Legacy's amps; I wonder who's making these. |
There's a new review for the Technics SU-R1000 by Andrew Robinson over on YouTube: https://www.youtube.com/results?search_query=technics+su-g1000 He thinks very highly of it as well as the lesser powered SU-G700, which I've been eyeing for awhile. All the best, Nonoise |
Douglas Schroeder, Where did the information come from that you posted about the Legacy Ultra being a bridged amp using both channels on each stereo module in some kind of bridge? "a differential topology"? As far as I know, each channel is already bridged and has a differential input stage. You cannot bridge a bridge. Check this picture out of another guy who has this amp.....you will see all the channels on top have no wires connected to their output terminals. You can clearly see a black and red wire coming out of the bottom speaker output terminals. So, it looks like they just buy stereo modules and the "ultra" version is just using one side of each stereo module as a mono. If this is so, then what you have is stock IceEdge modules in a box (no fancy differential bridged circuit)....I could be wrong. You can buy a dual mono IceEdge amp from Rouge Audio Design and it can be delivered for a little over $1500....way, way less expensive than Legacy. I worked on the IceEdge modules for 6 months making them sound way better.....and also using super AC inlet, wire and my binding post bypass system. I can improve any IceEdge based amp the same way.....way better sound for very little money. Stock IceEdge is OK but modded it is more pure and dynamic. https://systems.audiogon.com/systems/5078#&gid=1&pid=11 Go to picture 11 and if you click on it once open, it will enlarge. |
I am waiting on a Class D amp that will sound as good as my AHB2 monos but have much more power (2 Ohm). I was hoping that Purifi would release a second generation amp module but looking at their web site it seems they have moved onto driver design. I have a D-Sonic M3a 800s Class D amp (Pascal module) + CODA 07x preamp on the floor standers that the AHB2 previously drove. It is a better power match but I still think the AHB2 is the best amp I ever heard. The AHB2 is the quietest and cleanest amp I have ever heard. My AHB2 monos are now doing headphone duty with the CODA 07x preamp. A perfect combo for my RAAL SR1a headphones. |
Yes, I thought that was a neat feature, the way the Technics "listens' to the cartridge and applies its magic to it. I found another reviewer who's somewhat of a Technics fan and his take on the R1000 and how it compares to a much more expensive Technics line: https://www.youtube.com/watch?v=YePQyDV52Zk He, too, is a big fan of what the Technics does for LPs. I believe it can store up to three different settings for as many cartridges. All the best, Nonoise |
I just want to mention one other note on the Edge A2-300 Class D amp. It uses the exact same Ice Modules that Jeff Roland uses in his latest Class D amps and the Edge A2-300 puts out a potent 150 watts per channel in to 8 ohms and it is bridgeable in to mono so one could use two of them for more powerful monblocks. |
ricevs, I checked with Legacy, and you are correct; the amp is not differential, but the bridged modules when run mono are. I have revised the article accordingly, and it will appear revised on the website. The channels are not using only one half of a stereo module, but are bridged. As regards your claims of performance with your mods, a couple thoughts. I review retail products, not much in terms of mods. So, I recuse myself from it. In addition, and there is nothing personal in this at all, unless you have a proper business and discuss what precisely you do in your mods, I would not recommend anyone send off equipment to such entities. I deal with people who make claims on equipment every week, and I have learned personally and professionally that the modded gear has no advantage over any other given stock retail gear. YMMV :) |
James at Legacy Audio here- I wanted to expound on some things Additionally, when you look at the dynamic range capabilities of stereo source material (which is predominantly recorded at 24 bits) and the emergence of streaming high resolution two channel audio as well as Atmos surround sound, using an amplifier that can keep up with the dynamic range is increasingly beneficial. I invite anyone who wants to further understand the advantages of these incredible amps, to stop by and hear what they can do! All the best, James |
Douglas, I consider what you said about modding to be ridiculous. Every new product is a revision or mod of the last one. Many companies just use different techniques or better parts they learn anew in the next model.....It is a mod. We keep learning. I have been manufacturing and modding gear since the 1970s. What I do works. My customers can attest to it. You have never heard anything I do. You have no knowledge whether my mods benefit sound. Does your modded shotgun cables change the sound for the better?.....it is a mod. When you swapped op amps in your DAC.....that was a mod. Everything is a mod. Read my website. I describe tons of things I do and even show pictures. Everything is a mod....everything makes a difference. No manufacturer has all the info. This game is infinite. The more I know....the more I know that I know nothing. I would certainly never put down what anyone says about what they hear. I only believe in the truth. The truth is what I hear. I only want happy customers......I have happy customers. Love is the truth that is always present. Love me.....I love you. James, Of course, when you run just one channel of a stereo module then the whole 1200 watt power supply can power one channel only....same as using a mono module. Are you using both channels of the stereo module in some kind of bridged circuit? The output of each channel is already floating (not ground referenced) and bridged. The input stage is fully differential. How do you bridge two already bridged channels together? The pictures of the iV4 Ultra amp I showed, show no output wires coming from one channel or input wires to that channel either. Are you running wires underneath the board? As far as I know, you cannot bridge two channels together that are already bridged. You need ground referenced outputs to bridge. IcePower has always had differential Half bridged circuits on its outputs. |
Well, how about the Rogue Audio Hydra? http://www.rogueaudio.com/Products_Medusa.htm It seems different in design approach. I would gladly try this one. Or Mola Mola Kaluga seem to have some followers .... https://www.mola-mola.nl/kaluga.php |
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douglas_schroeder ... it’s time for you to reveal your industry affiliation ... You say goSuch righteous indignation! It took me less than 1 minute to figure out that Ric is Electronic Visionary Systems. I’m sure Doug would have found the same info if he’d tried. |
Doug, You are making a mountain out of a mole hill. You stated something in your review that made no sense to me.....the bridging thing. So, I asked you where you got that information. Then you repeated the same information, that to me, still makes no sense. I showed you the insides of your amp and that it shows no hookups to one channel of each board. I am interested in TRUTH. Are you? If you want to find out what is really going on in the amp (to back up what you think is going on) then all you have to do is take off the cover of the amp and take a good look inside and see if I am right or wrong. It is either a stereo module using just one channel (what I think it is, again, I could be wrong) or it is some weird way to hook up two bridged channels together that I have never heard of. I am semi retired. I make practically nothing. I don't have products to protect. In fact, if I were still selling my IceEdge moduled amp I would remove the coverings of my mods to the board and let everyone see every single thing I do. No one would be tweaky enough to even copy me. What I do is not financially viable to run a company. What I do is far to tweaky and time consuming. I am mostly an enthusiast who is a crazy tweaker. I love to turn people on to really good gear that costs very little. I mostly love to teach people how to fully live in the moment......in the love and joy we really are. I am sorry you feel threatened by my inquiry. I only want the truth to be told. Please follow up and show us the truth. We are all ignorant. No one knows everything. We all make mistakes, we all assume things and tell others and then realize later that we were wrong. We are all bozos on the buss. However, we are all divine and beautiful. We can correct our mistakes. We can forgive ourselves and others. A sense of humor is always the great healer. Lighten up, oh beautiful one. |
Ric, I really appreciate your last post! Cleeds’ post enlightened me to the fact that I did not see the disclosure of "ricevs", as I am not familiar with your company. I removed my two previous posts, as I now consider them unproductive to continued discourse. I also want the truth, which is what I was probing for in those posts. I do not have the topological answers you seek; you would need to discuss with Legacy Audio. I mean no offense when I state that no one can tell whether a modded component from any modder would sound better than any given stock component from another manufacturer. I do understand you comment about all components being modded. I have compared a fair number of tweaked/modded products, and I have found no direct correlation between modding being universally superior to any other given stock component. That is why I state one simply has to make comparison. Others may have different experience, but that has been my experience. In reply to your comment, "What I do is not financially viable to run a company," you are not alone. I have heard similar several times from other manufacturers. |
This is what I think. Legacy buys stereo modules. They use them in all the amps. So, an i-v8 would have 4 stereo modules (8 channels). The regular i-v4 has two stereo modules (4 channels). The I-v4 ultra has 4 stereo modules (8 possible channels) but they use just one channel of each module so they are basically mono amps. This gives more power for each channel and zero cross talk. Each channel is already bridged, so you cannot bridge an already bridged amp. So, no the i-v4 ultra cannot be bridged in any way. It already has 1200 watts into 4 ohms on each of its 4 channels. How much power do you need? I believe the i-v2 dual mono stereo amp has 2 stereo amps and then just uses one channel of each amp to make it mono. |
I have had mostly good A/AB amps over the years and one tube amp. Some amps were hell with some speakers, so amp/speaker synergy is still critically important no matter what you think you prefer. (I prefer a 'system sound' which starts with the best speaker I can afford with the sound I prefer, and then adds electronics in support of it.) I now use a W4S STI-1000 integrated in my main system. It's my first Class D amp. I use the DEAD SILENT pre-amp switching into a dsp room correction unit, then back the the STI-1000's power amp section. This feeds a pair of highly resolving (perhaps slightly warm) near full-range two-way loudspeakers. The sound works for me with stunning detail and treble resolution second to none with never a bit of fatigue at all. The bass is solid and tight within limits of the speaker's ability. I agree with other W4S owners in their characterizations, and have no doubt that the ST-1000 amp can feed the load of the Martin Logan CLS. I owned SL3s as mains for sixteen years (and still own them but now displaced as mains). If I was made of money I might experiment with other amps but as of now I fortunately do not feel the need. The W4S Class D works extremely well in my system. I have none of the Class D prejudices others rant about. |
To @ricevs I am a long-time Legacy customer of many of their speakers and also happen to be an owner of the i.V4 Ultra amp since May of 2020 (very happily and very impressed I might ad). The "ULTRA" build is using 4 stereo 1200AS2 boards with each single board as I understand it being dedicated and applied to power 1 channel. What I can tell you for sure is that I have been extremely happy and impressed with this 4-channel amp (and have a friend with an i.V3 Ultra and another with an i.V2 that are equally impressed). I, like the 2 guys that I know, have been in this hobby for about 3 decades each and were early on firm tube amp lovers followed by "big expensive solid state lovers and bigots" for Class A and/or AB designs costing 10s of thousands of dollars and weighing 100-200 and more pounds. Note I still love great tube, Class A and AB solid state for the record and appreciate the merits of any reference-level amplifier. I will not throw out manufacturer names for things I've owned and even more that I've heard but I will say there are some big names on the list that I've owned and more that I've heard deeply that I remember and respect very much that today would have a hard time competing with what I'm hearing out of this Legacy i.V4 Ultra so I am inclined to agree with everything qualitative that is said in the review based upon my direct listening experiences only owning this amp. I don't however want to get into a '&*^%^#$' contest with anyone who takes umbrage at the claims in the review. It's a fantastic, musical, dynamic, detailed, powerful amplifier design that weighs a fraction of what I'm used to dragging up and down stairs, etc. and costs what I think is an incredibly reasonable price. I'd suggest to anyone that it is well worth a listen to a well broken-in demo on a good system and do some careful listening; you might be very surprised and pleased at what you hear! |
"This is what I think. Legacy buys stereo modules. They use them in all the amps. So, an i-v8 would have 4 stereo modules (8 channels). The regular i-v4 has two stereo modules (4 channels). The I-v4 ultra has 4 stereo modules (8 possible channels) but they use just one channel of each module so they are basically mono amps. This gives more power for each channel and zero cross talk. Each channel is already bridged, so you cannot bridge an already bridged amp. So, no the i-v4 ultra cannot be bridged in any way. It already has 1200 watts into 4 ohms on each of its 4 channels. How much power do you need? I believe the i-v2 dual mono stereo amp has 2 stereo amps and then just uses one channel of each amp to make it mono." To @ricevs great post....that is what I understood last year when I spoke with Dudleston at Legacy before deciding to buy the i.V4 Ultra.... |
I am sure the Legacy amps are very good. Stock IceEdge modules in a box. However, most people would want the dual mono iV2 amp that retails for $4785 (most don’t need or want a four channel amp like the $8700 iV4 Ultra). You can buy a stereo dual mono amp using mono IceEdge modules from Rouge Audio Design in Italy and have it delivered to your door for $1600.......a savings of $3185!!!!! I can also do mods on any IceEdge amplifier for very little money that improves their sound. Of course, many do no like buying via mail order and also from small companies and also don’t care for modding. I fully understand. The IceEdge modules are seriously reliable. |
Additionally, when you look at the dynamic range capabilities of stereo source material (which is predominantly recorded at 24 bits) and the emergence of streaming high resolution two channel audio as well as Atmos surround sound, using an amplifier that can keep up with the dynamic range is increasingly beneficial.While this is certainly true, it has nothing to do with a properly functioning amplifier. Usually it has more to do with making sure that the speakers used with the amp are such that when the dynamic range of the music is expressed, you hear everything without distortion, even if its at lifelike levels. As an example, in 1959 RCA released the Soria series recordings. Dorle Soria came from Angel to work with RCA and produced upscale recordings and packaging. One such recording is the Verdi Requiem, which is recorded without any compression. The second cut on side one has dynamic range that can bring many systems to their respective knees. But if you have enough power and you have easy to drive speakers its no problem! |
While this is certainly true, it has nothing to do with a properly functioning amplifier. Usually it has more to do with making sure that the speakers used with the amp are such that when the dynamic range of the music is expressed, you hear everything without distortion, even if its at lifelike levels. As an example, in 1959 RCA released the Soria series recordings. Dorle Soria came from Angel to work with RCA and produced upscale recordings and packaging. One such recording is the Verdi Requiem, which is recorded without any compression. The second cut on side one has dynamic range that can bring many systems to their respective knees. But if you have enough power and you have easy to drive speakers its no problem! Great example on the Soria series,....absolutely spot-on. As to the rest of the reply, you cannot have one without the other, i.e. a speaker that will do it when the amp cannot accomplish the same goal and vice versa leaves you with the system not being able to do it so with all respect, it does have to do with the amplifier’s capabilities. |
The i.V Ultra series of amps from Legacy Audio are not stock IcePower modules in a box. That discussion needs to be discarded. I have not shared everything I know about the design. I am not interested in sharing it all, as well. Further, I presume that Legacy’s use of one channel with a dedicated power supply per channel could outperform all the mods of the EVS amp. Or, vice versa. Obviously, no one - including EVS, Legacy, or myself - knows short of an actual comparison. |
As to the rest of the reply, you cannot have one without the other, i.e. a speaker that will do it when the amp cannot accomplish the same goal and vice versa leaves you with the system not being able to do it so with all respect, it does have to do with the amplifier’s capabilities.If the amplifier is unable to follow the waveform presented to it (which is the source of all dynamic contrast) then it will distort. Perhaps a bit counterintuitively, if a particular amp is **more** dynamic than most others (for example SETs) its also because of distortion. In the case of SETs up to about 20% of full power their distortion is pretty benign. But above that point, the higher ordered harmonics become more pronounced. Since the ear uses the higher ordered harmonics to sense sound pressure and because transients is where most of the power is, when the higher orders show up on the transients, the ear interprets that as 'louder on the leading edges' IOW more 'dynamic'. Its a simple fact that when audiophiles talk about dynamics, about 90% of the time they are really talking about distortion, and you can safely replaced the word 'dynamics' in that conversation with 'distortion' without changing the meaning of the conversation. Put another way, amps that sound more 'dynamic' are very likely to do so out of distortion and nothing else. The dynamic character of the music should come from the source, not the amp, that is if the amp is accurately reproducing the signal! |
Actually, I should add to my last comment. A simple comparison is not terribly informative. A comparison between amps in use with 4-6 speaker systems, and from 12-18 discrete systems yields an entirely different assessment (perhaps consistent with first impression, perhaps not) than simply use in one system with one pair of speakers. Short of such a thorough familiarization with an amp, the judgment of which is better is quite limited. That is why in my review I built more than a dozen discrete rigs with several pairs of speakers, my methodology. I pay no attention to what many think is SO important, break in. I build systems - and get a far better, global understanding of the performance of any component. :) |
If the amplifier is unable to follow the waveform presented to it (which is the source of all dynamic contrast) then it will distort. All so true....great post! I would only add that great amps that sound more dynamic can also do it due to extremely low distortion and better execution of instantaneous power delivery. |
