verdict on class D amps?

I think the verdict is still out at this point. They have matured far beyond subwoofer use at this point. Whether they have moved into a viable alternative to conventional amp circuits if the big debate. As is always the case, the implementation is the most important factor within any technology. If the next 5 or 6 years sees the same advancement as the past 5 or 6 , then I think we may see a dominant force in the making

I recently changed out from Audio Research gear to Jeff Rowland including the 501 Monos. Going from tubes to Class D solid state in this case is NOT GIVING UP A THING; except changing out tubes, rebiasing equipment, heat, electrical bills and assorted hums and buzzes. No knock agaist ARC, it's just that the Class D technology isn't a thing of the future. It's here now. Enjoy!!

Read what stanwel says in a different thread,he sums it up better then i can about dig amps,

I'll also give a thumbs up on the Class D amp. I'm using the Cullens Circuits (Wyred4sound) and find it very neutral sounding. So much so that it really picks up the personality of the ARC LS26 preamp, and has the power and head room to make B&W 802D's (bi-amped) really sing. Be prepared for 300-400 hours of break-in time to get the best sound.

Ignore Coffeey and Stanwal.

They are dinosaurs refusing to enter the 21st century.

Neither of them has a clue.

Here is a useful thread on The Absolute Sound's website: http://www.avguide.com/forums/digital-amp-advice-maggie-36
I'm not unbiased, since I'm using an ARC 150.2 (what ARC calls "class T" but the rest of the world would call "class D") with my old Maggies, so in the referenced thread, I find Chris Marten's comments the most useful.

Coffeey and Stanwal suffer of Audiophilia Nostalgica, a very painful form of the more common audiophilia nervosa that we all suffer from.

Rather, go listen to various switching (class D or T) amps and decide for yourself if any of them are for you. . . they can sound as different from one another as birds in a forest. G.

Verdict???
There is and always will be something better :-)
Thats a guarantee.

And it will ultimately come down to the speaker its paired with... However I will say none of the digital designs I have heard over the last 10 years will match any Pure Class A amps done well.. Solid state or Tube, so to me I still gotta deal with some Heat, or low efficiency, or reliability... Thats all people want class D for, to save 3 dollars a month in electric, have no heat off the amp, or simply worried about buring up a tube, and finally because they just have a speaker requiring excessive power and want enough power on tap for cheap dollars.

Nothing wrong with those reasons so if it works for you do it!

I bought an Calss-D amp based on the internet hype (Bel Canto evo 4 mk II), then tried ICEpower based models, but in the end, I returned to hybrid (Lamm M1.2R) and eventually, to tubes (ARC Ref 110). IMO there is no comparison.

But as Try have said - try one in your system.

I replaced a Pass X250.5 in my system with a pair of Channel Island D-200 monos and it sounds just as good as it always did. I put $2k back in my pocket (I purchased used), and don't have the heat or strain on my back like I did with the Pass. As a side note, for what it's worth, I've been a musician since the 60's and I own my own recording studio, so I feel I have a pretty good ear for sound quality. My speakers are SP Tech Timepiece 3.0s which are 85 db sensitive, and I don't need a sub. My speakers go down to 30hz and the D-200s push them with ease. I say give'em a try. You may or may not like them. I do.

I had been skeptical of Class D amps based upon various comments but then I listened to a setup consisting of the Kharma Matrix MP 150 amps driving Kharma Ceramique 3.2 speakers with a modded Marantz CDP and CJ Art pre and the setup sounded excellent with female vocals and piano in my very short audition (due to other reasons). Definitely not a technology to write off without auditioning.

The Channel Islands are great amps. I prefer the Hypex UCD class D technology over the B&O ICE class D type. I sold a Karan $6k integrated and went with UCD Class D and thoroughly enjoy it with a tube preamp.

I have X250.5 & replaced with Nuforce Ref9SE V2 , it actually sound better than my Passlab in my system. I took my Nuforce to compare with a big Krell, wow my friends were amazed how good they sound in his system. I am looking for a match tube preamp for my Nuforce, I was told on the phone class D amp are just toys by a local audiophile store after 20mins with him, he told me to come to the store and listen to their reference system. And that is what music sounds like. So i took my Nuforce down to him, we sat down and listen to his system, wow it did sound better than my system. Then another 10mins on class D toys lecture, he finally agree to put on my Nuforce. After 10 mins music on cd, we have 2 hrs of music on his Lp collection. He acually apologize for what a hard he was before , that tell you how good it sound in his system.

I love my Gilmore Raptor class D monoblocks. Coupled with a Supratek Chenin preamp and Infinity RSIIb speakers, they sound as good as anything I have heard.

yeekim I've been using nuforce ref 9 amps for more than three years. I have heard every negative comment in the book in that time about class d amps. Yours and the audio store salesmens finding are what most have heard when a true audition is made with class d amps. For this reason those negative comments have diminished drastically as more audiofiles listen to there favorite music with these fine amplifiers. Clean, detailed, powerful, cool operating, unmasked clear sounding amps most certainly have a place in high end audio. There will always be those who will bash anything different/new unfortunately. From my perspective I'm happy for all audiofiles who are satisfied with there choice of gear. Enjoy your music while you can.

I think the technology has improved quite a bit. But it still varies from manufacturer to manufacturer. I had attended a demonstration about 18 months ago at the local dealer with both VTL and NuForce driving a pair of USHER BE-20s. The VTL was hooked up to the speakers first, and they sounded phenomenal. NuForce's reference monoblocks were then put to the task after the break, and I got to sit in the sweet spot. My personal take was that the NuForce exhibited a lot of the undesirable characteristics that everyone had been complaining about digital amps. (At least to my ears)

Moving forward 12 months to RMAF 2008 in Denver. There were a good amount of manufacturers showing off their digital amps. Some still exhibited those undesirable characteristics, but some sounded very promising. One that stood out the most, for me, was Wyred4Sound. I would love to have the opportunity to bring one of their amps home to compare to my Pass X350.5 side by side.

But I think it is safe to say that digital amps, in general, are moving towards the right, and a very promising, direction.

FrankC

Frank, you hit the nail on the head on class D amps. . . which are not digital devices btw. . . They are evolving rapidly, but like with amps based on any other technology, they vary in sound by model and by manufacturer. . . always have, and always will. Guido

Guido - that is an important distinction. Many people object to principle alone (switching) not understanding that time can be as analog as frequency or voltage. They probably already have CD players or DACs with delta-sigma D/A converters, SACD players or DSD recordings - all of them class D like (PWM).

Frank do you know if the Nuforce amps were well broke in? They need at least 200 plus hrs for a reasonable break in. Which model was it? I respect your feelings and thoughts. Ive had all versions of the ref 9 series through upgrades. By far the latest V2 technology is the best version. Like i posted above if you are happy with your system good deal.

thanks for all the info!!! I unfortunantly do not know of a local shop who carries any class D stuff.... thus I can only go by what I read on these forums & also on the manufacturers websites.

Can someone list a few different manufacturers of class D/T amps that I should consider?

The only manufacturer website that I have read about is the Seymour Ice stuff

"Can someone list a few different manufacturers of class D/T amps that I should consider?"

Acoustic Reality www.acoustic-reality.com/
eAR202, etc (ICEPower)

Aivin www.acoustic-reality.com/
DT300 (www.acoustic-reality.com/) (Tripath)

Analog Research Technology www.acoustic-reality.com/

AudioArt (NL) www.acoustic-reality.com/
Van Medevoort MA240 (Hypex UcD)

Audiodigit www.acoustic-reality.com/
MC 8x100 (Tripath)

AudioResearch www.acoustic-reality.com/
150.2, 300.2, 150M (Tripath)

AV123 www.acoustic-reality.com/
X-Empower, xAmp (prelaunch (www.acoustic-reality.com/))
(Philips class-D?)

B&O www.acoustic-reality.com/
(ICEPower)

BelCanto www.acoustic-reality.com/
Evo (Tripath) eOne (ICEPower)

Bertram www.acoustic-reality.com/
(ICEPower)

Carver www.acoustic-reality.com/
300.2, 700.2, 1200.2

Cary Audio www.acoustic-reality.com/
A 306 power amplifier (www.acoustic-reality.com/)

Channel Islands Audio www.acoustic-reality.com/
D100, D200 (Hypex UcD)

Chapter Audio www.acoustic-reality.com/
Couplet Power Amp (proprietary WMP class-D)

D-Sonic www.acoustic-reality.com/
Magnum (www.acoustic-reality.com/) (ICEPower)

DIYCable www.acoustic-reality.com/
Exodus (www.acoustic-reality.com/) (Hypex UcD)

Egosys www.acoustic-reality.com/
Audiotrak DrAMP (www.acoustic-reality.com/) (Tripath)

Elan www.acoustic-reality.com/
D1200, D1600 (12 and 16 channel power amps, Tripath)

Electronic Visionary Systems www.acoustic-reality.com/
EVS-2 (www.acoustic-reality.com/) (ICEPower)

Flying Mole www.acoustic-reality.com/
(proprietary class-D)

Gilmore Audio www.acoustic-reality.com/
Raven, Raptor, Dragonfly (www.acoustic-reality.com/) m/ch (looks like ICE)

Halcro www.acoustic-reality.com/
Lyrus

H2O Audio www.acoustic-reality.com/
M250, M500 (ICEpower)

Integra /Onkyo www.acoustic-reality.com/
DTA 9.4 (www.acoustic-reality.com/) 7x120W 8Ω

Jeff Rowland www.acoustic-reality.com/
(ICEPower)

Jjaz Audio www.acoustic-reality.com/
(ICEPower)

Kharma www.acoustic-reality.com/
MP150 (www.acoustic-reality.com/)

LC Audio www.acoustic-reality.com/
Predator SE (www.acoustic-reality.com/) (ZapPulse)

Marantz www.acoustic-reality.com/
Opsodis ES-150 (www.acoustic-reality.com/) (D2Audio) 2ch virtual surround

Medius [DK] www.acoustic-reality.com/
A II, A III (www.acoustic-reality.com/)

MG Audiolabs www.acoustic-reality.com/
Symphony (www.acoustic-reality.com/) (Hypex UcD)

Midgard Audio www.acoustic-reality.com/
(ICEPower)

MindCraft (NL) www.acoustic-reality.com/
Media Amp One (www.acoustic-reality.com/) (Hypex UcD)

Murano-Audio (TW) www.acoustic-reality.com/
P500, P1000 (ICEPower)

NHT www.acoustic-reality.com/
Power2 (www.acoustic-reality.com/), Power5 (www.acoustic-reality.com/) (ICEpower)

Nuforce www.acoustic-reality.com/
Ref 8, Ref 8b, Ref 9 (nPhysics proprietary class-D)

NuVo Technologies www.acoustic-reality.com/
NV-P2100 (www.acoustic-reality.com/)

Onkyo www.acoustic-reality.com/
A-1VL, A-9755, A-9555 (www.acoustic-reality.com/) (?)

PSAudio www.acoustic-reality.com/
GCA, GCMC (ICEPower)

Red Dragon Audio www.acoustic-reality.com/
(ICEpower)

RedWineAudio www.acoustic-reality.com/
Clari-T, Lotus (Tripath)

Rotel www.acoustic-reality.com/
1077 (7x100), 1092 (2x500) (ICEPower)

Sharp www.acoustic-reality.com/
SM-SX1, SM-SX100

Sonneteer www.acoustic-reality.com/
Brontë (Tripath)

Sony www.acoustic-reality.com/
TA-DA9000ES, TA-FA1200ES (www.acoustic-reality.com/) (S-Master)

Spectron www.acoustic-reality.com/
Musician, Troubador (int amp w digital inputs)

TactAudio/Lyngford www.acoustic-reality.com/ www.acoustic-reality.com/
Millennium & others (Equibit)

TEAC Esoteric www.acoustic-reality.com/
AZ-1 pre-main (translated (www.acoustic-reality.com/))

ThetaDigital www.acoustic-reality.com/
Virtu PowerDAC (www.acoustic-reality.com/) (Zetex class-Z)

UniwaveTek www.acoustic-reality.com/
Anaco II

Yamaha www.acoustic-reality.com/
MX-D1

You can also check Meridian and Genesis

Kijanki now your a audiophile who knows his class d amps. Nice post just ask and you will receive.

This list was compiled a while ago and needs to be updated. I found, for instance, that International Rectifier (famous for Mosfets) came up with class D amp (thank you Magfan for the info).

& to think I was expecting a handfull of options

THANKS

I agree with those who say you need to try it for yourself.

I've listened to a lot of Class D amplifiers, and so far, none has ever come close to having me consider a move out of a tube amplifier. To this point, the only two that I have appreciated are the Spectron and Veloce. I've not heard the H20, but would like to. Certainly, if I picked up a pair of Apogee loudspeakers, I'd seriously investigate the H20.

My biggest problems with the lion's share of Class D amplifiers are analogous to the two problems I have with CD. First, while there may be the initial impact of the note in the low frequency, there is simply nothing (or, almost nothing) behind it, leaving the foundation of the music lacking the proper fullness, warmth, and weight. Second, there is something I perceive through the rest of the musical spectrum that for whatever reason, does not allow me to fully relax and immerse myself into the experience. With CD, I've narrowed it down to the music being "chopped up" into not a fine enough material so that the comparison with the way analog flows like water is stark. I have not spent enough time with digital amplifiers yet (the longest I lived with one was 3 weeks) to fully put my finger on it, but there is an inherent lack of emotion in the sound. I don't want to call it coldness per se, as it's not completely that, but producing the flesh and blood of music, is something they so far, miss.

DISCLAIMER: The manufacturers of Veloces are very close friends of mine, so take my opinion with the appropriate grain of salt.

What most have found using these very revealing amps is what you put into them you will get out. Power and power cords also come into play along with isolation. But the main determination of sound from class D amps is the source components. IMO

I am big on vinyl so 100 percent of time for serious listening sessions its lps. Throw in my tubed preamp and those Nuforce class D amps are a non issue for sound production for me. Fast, powerful, revealing, sweet.

This could be a good reason for my having absolutely no trouble enjoying hours on end of some of the best sound these ears have had the pleasure to hear, fatigue free.

Like i have posted many times before the amount of gear available to us today is beyond the ability to try it all. If you audition class D amps and they mate to your system great if not move in another direction.

The most important thing is enjoy your favorite music as often as possible.

I also like the Hypex UDC module better than ICE. I have five CI D200 amps in my multichannel system.

However, before I bought the monoblock CT amps I used three CarverPro ZR1600 stereo amps which are based on the TriPath module. IMHO, the ZR1600 amp sounds every bit as good as the CI D200, and the D 200 is well regarded in audiophile circles. (At the moment the ZR1600 amps are powering the six drivers of my three custom subwoofers).

But the real point is that the three ZR1600 amps (6 times 600 watts) cost me the same price as my first two D 200 amps (2 times 350 watts). Today I see they go for about a grand each.

If anyone would like to sample a digital amp the ZR1600 is a good place to start.

I auditioned the SeymourAV amps for a while, comparing them to a Mark Levinson ML-9. In the end, I returned the SeymourAV amps and ended up with a Spectron.

it was a difficult decision, but it came down to a very subtle high frequency veil that was present on the SeymourAV. Actually, my friend felt it was very obvious and not subtle at all, but I think he's just picky and overstating the problem, which seems to be a common thing amongst audiophiles :)

I've had several people tell me that this veil is a common problem with all ICE module amps, although I've also one person state that wasn't the case.

Regardless, the SeymourAV amps are the only ICE-based amps I'd consider, simply due to the aesthetics and cost issues (I'm assuming they all sound pretty similar, which may or may not be the case). I find the Wyred amps to be "aesthetically challenged", to put it nicely, and the SeymourAV also has a 10 year warranty, which beats any ICE amps I've seen so far. The cost is also towards the low-end of the ICE amps (I think some are more than twice the cost).

In the end, it really depends on what you prefer. Everyone seems to have different interpretations of what they hear.

Btw, I really wish people would stop calling these "digital" amps. Please do some research, because they are NOT DIGITAL! Continuing to call them that, while also dismissing them only weakens your argument. No offense intended.

Careful circuit design & quality parts will always produce a better sounding amp and this applies to both digital & analog amps. Some cheaply manufactured digital amps are a good choice for subwoofer duty since they deliver more power for less money, very efficient, and produce very little heat. But never dismiss them as an excellent candidate for a high-end-rig. There are some digital amps out there that are manufactured to the highest industry standards and produce amazing results, must be heard to be believed!

Sorry Nospam, I have used the term digital to keep in line with familiar words.

PHD - do you call Switching power supply (SMPS) "Digital Power Supply"?

Proper term for these amps is "Switching" or "Class D" (there is nothing digital inside)

It depends on your taste which will be determined by your ears and what your brain's sonic preferences are. I have listened to tube amps (Music Reference), hybrid (Audio VanAlstine 250 wpc Fetvalve 550, and class A solid state monblocks (300 wpc Sheng Ya). I also have listened to the Wyred 4 Sound 125 wpc amplifier.

Here is what my ears said to me when I switched out the Music Reference tube amp for thw W4S amp. The W4S amp is smooth, very smooth, silky smooth - almost unnaturally smooth. The sound is very clean but not as big hipped as the Music Reference. Can't say much about the bass as I was running a subwoofer on a pair of bass shy speakers, the Spica Angelus. It is just a very different musical presentation that my solid state, hybird or tube amps and since it has, to my ears, a distinct sonic signature it won't be flick everyones bic.

I like the W4S sonic signature. My amp is not fully broken in so it may get better. It is pleasing to listen to though different.

Jaymark - that was my impression. SS integrated, I had before class D amp, sounded in comparison "brassy". I'm not sure, with my limited experience, how best amp should sound, but I have very liquid smooth sound now. Sibilants, I had before, disappeared and clarity/transparency got better. One thing I noticed was that sound got leaner at lower midrange. I replaced speaker cable (AQ Indigo) with better one (AZ Satori) and the lower midrange got much fuller.

Kijanki, lean in the mid-bass is, I think, what I was getting at when I said that is was not as big-hipped as the Music Reference tube amp. My W4S amp is not fully borken in but it is on the silky, clean, but lean side of musical presentation......

I hesitated between AZ Satori and some other cable until I found few reviews that complained about a little fuller lower midrange - that was exactly what I needed. AQ Indigo was, in comparison, very thin sounding. Satori is not only more refined (clarity) but has very pleasant silkiness on the top.

As for breaking in - it goes thru "stages" (as any break-in) for very long time. My small Rowland 102 stopped at about 500hrs or at least I was unable to detect anything - so be patient. It becomes a little less "forward" and more refined/musical.

Hey Kijanki,

Thanks for that nice list of Class D amps!

Its in my back pocket for future reference.....

You're welcome.

Kijanki, I meant mid-range not mid-bass in my last response. Musta had a bit of brian ischemia........

Jaymark - I assumed that.

Kijanki, do you happen to have the switching amps list as an Excel file to share with us? Thanks, Guido

No Guido. It wasn't my compilation to start with (I found it somewhere on internet) and it needs updating. It would be nice to enter updated list into Excel but I'm too lazy for that.

When I bought my Rowland 102 I knew only about Bel Canto and NuForce but this list was a shocker.

There is a dealer and Apogee speaker restorer extraordinaire near me who has
been courted by Bel Canto, and Spectron. He ran both of their most up to date
amps for long enough to come to the hasty opinion all class D amps must be
poor sounding.

I changed that. I took my entire system, including the speakers, to his place. His
verdict? - the two afformentioned amps, "Do not hold a candle to your
H2O amps."

I can't really blame Bel Canto or Spectron for their bad presentation. Like I said, I
took my whole system. There are those of us who have been experimenting with
ICE amps for years. I have learned a lot in that time. Taking my system showed
the H2O in it's best light.

Muralman1 - It is subjective. What sounds good to you (and him) might not sound good to others (I don't doubt that your gear is great). What is important to me is the bang for the buck that you get with class D. I don't have to have (and cannot afford) the best amplifier in the world, but I always like very good deal. I can also use money to update my speakers.

I'm very surprised that people make, as you said, "hasty" decisions about technology jumping from "poor sounding" to "great sounding" with nothing in between.

When it comes to the passion of most audiophile his or her thoughts and believes are right and all else wrong unfortunately nothing will change there minds. Even when they hear new technology in a component. I've been in these hobby for over 40 years had the same system for 25 plus years. Guess what new technology came along and here i am with yes Class D amps and enjoying music more than ever.

I may have passion mixed up with hard head or other bone headed words.

Muralman1,

Can you tell us more about what preamps were used during the test? In my experience, you can have the highest regarded components and still be able to get poor sound. System synergy is extremely crucial.

In the past, I've auditioned a piece of audio gear in another system. I've then purchased it only to realize that it doesn't sound as good in my system.

I'm extremely satisfied with the current state of my system. It'll be very hard to associate the sound of my system with tubes, solid state, etc. It sounds more like live music, which has always been my goal. I was able to accomplish this quality of sound with the Spectron mono-blocks (with Bybees) and the newly released Joule Electra Marianne Electra Memorial Edition preamp.

Best,

iSanchez

Tvad in my case your response:

On the other hand, I find that sometimes even when someone tries something new and chooses to reject it, others who have chosen the new product can attack the listener's choice as wrong headed.

I have posted many times if you are happy with your gear and sound thats coming from it great i'm happy if you are happy.

Class D amps have come a long way just has tubed gear and SS also. Better materials and ideas have improved these components of our systems.

In the end we all get better sound from our gear.
As Kijanki so wonderfully noted your ears and mine hear sound differently. Along with our rooms that fact causes a lot of the posts on this web site.

Enjoy the music now while you can.