Whose got best class D at this point?

Bel Canto,PS Audio,Redwine what am I missing out there for either hi-effciency speakers like the Redwine Sig 30 (great review in 6moons and sounds like it would be great with Silverlines or my German horn Odeon Tosca's) or for current hungry speakers the PS GCA250 or Bel Canto 300.Think after years of onventional SS and tubes might want to take plunge but want guidepost to best bet for the money.
My GCC-100 with the Underwood mods sounds fantastic, especialy since you can forgo using a preamp. The best SS I have heard, and reasonably priced - though they so take a long time to break in. (and I also have them on Powerplants Premier - which I suggest whichever amps you get.)

That being said, I am now using them only for the bottom end. I ended up getting my Atma-sphere MA1's retubed and liking how they sound powering the mids and highs.
I run the Channel Islands D200s and I've not heard any better...

I've only heard a few and they were of the lesser expensive models, but they are promising. Here's what I would do if I were in the market for a new class-D amp. I would verify which models sell quickly on AudiogoN and wait for one at a fair price. If you love it, great. If not, re-sell it for the same amount or very slightly less.

I think I would be considering mid priced units like the Red Wine Audio and Channel Islands. I would also ask for feedback over on Audiocircle where both of these manufacturers have dedicated forums.

BTW, I currently have a RWA Reali-T and it is very good for the price. Makes me totally rethink my need to own my other tube amps.....


Very interesting thread as I'm looking at the Bel Canto and Nu force integrateds. I like Ruebent's advice in his first paragraph but not the second. I've found users who contribute to the Audiocircle dedicated forums are enthusiastic advocates for the particular manufacturer's products. My observation.
I had the NuForce 9's and thoughtthe Edge G.5 was nicer. I found out after I intended to sell it, that NuForce requests that you keep *20 (twenty) feet between the amps and broadcast receivers (TV/Radio).
Edge tells me that 20 inches is good enough for their amp. The say that their upper lines have even better isolation. I like the sound of the Edge G.5.
The Audio Magic are very very good sounding as well. They are a bit less musical than the Edge; but have zero problems with their power supply transmitting FM static.
Depth is less with D class than with S.S. and I've heard this from owners and from Edge.
Best to you, it can be a great deal of fun.

I purchased the Red Wine Signature 30, and after trying many SS amps in the past and not being totally satisfied especially with the class-D amps, I can now say my search is finally over! this amplifer sounds nothing like any class-D. It is so much smoother and more musical like a good tube amp, but with very controlled bass and really nice dynamics that you cannot get with tube. What also really amazes me is the no noise, as it is battery powered with high current SLA batteries.

I am very happy. I hope you get to try one too!

Good luck with your hunt,

Hey Tim,

Of course you are correct that you must be cautious when taking advice from folks on a manufacturers forum, like the RWA or CI forums at Audiocircle. What I was trying to say is that there is a high concentration of actual owners of those brands at that site and you may get some advance notice of units coming up for sale before the item is posted for sale, if you kinda keep an eye on the site. That's how I got my Reali-T. I would never suggest that you use a manufacturers forum as your sole method of researching a product.


I can't say which is best, not having heard any other type of class D amp, but the Channel Islands D200's totally outperformed my McCormack DNA 1 RevA Gold. Haven't looked back and they have been the most satisfying amps I've ever owned in my 30 years in this hobby. Not to say I wouldn't drop them in a minute if something better I could afford came along, but I don't see them being beat any time soon.. at least for me.
Something to watch here:
My Von Schweikert VR-4JRs are driven by Bel Canto M300s and sound fantastic. No interference with radio, plenty of clean power, affordable. I had no dealers to compare other brands, just took a chance. Underwood Wally said I could return them if I didn't like them, but I kept them.

Thanks for the link. That should prove to be an interesting shootout.

The thing that interested me was the lower priced entries. The Little Dot recently sold for $299 on Ebay!
Thanks guys
First Tracer thanks for the shoot out tip.Tgrisham-I know Kal Rubinson (Stereophile reviewer Krl or Kr4 hear at 'Gon) uses the 300 for one of his rigs and ref 1000's for his HT's.Me think that the Bel Canto top pre is cool with adjustable gain and laod of front panle.Next Tracer thankls for the shootout tip.And Spiro I would think thateve though this hobby proves money does not mean results the Nuforce verus the Edge given the porice difference well the Edsge should (pardon me) have the edge.And Nuforce is not a full Clkass D but a hybrid.I wonder about the PS stuff an would like to hear it next to Chanell Island if I need power but with my 94db speakers right now I think that the Redwine 30 (or mono 70's) is the best for my current rig based one reviews.6moons gushed and it was the only non-tube unit to get a best of 2006 award.Now will see if the DEQX catches on and trnasitor and tube amps might go the way of the IBM seletrics and we live in a truly digital world.WEith the new Squueexe boes for Internet Radio (Roku tube feeding recievers)and inexpensive HD music servers (with Wifi)like the Olive plus cheap HD's (last check a Terrabyte was less than $500) it is becoming a digital world.
WOW! I'm constantly amazed at just how the number of manufactures is growing. While the "SHOOTOUT" has fourteen examples and growing some of the major players are missing. It's commendable that their including receivers and integrateds as well as power amplifiers. It will be interesting to see just how they compare these different configurations. So far I've been disappointed with many of the preamplifiers designs by these manufactures.
Think Vic is ight.Even vnerable tube outfit like Carry has a chip amp out now.

The "shootout" mentioned by TRACER is complete and the results are out on the Stereomojo site. As mentioned earlier, there are some major players missing from the shootout, however, the results might surprise a lot of people.

BTW, I've been using a Red Wine Audio Reali-T (Clari-T integrated amp, plus Scott Nixon DACkit in one box) for a while now. I've got a couple of very good SET amps sitting on my storage shelf. The Reali-T is just too easy to live with and it sounds great too.....


You might also want to look at the Winsome Labs unit, it got good reviews on Audiocircle. http://winsome-labs.com/
I love my Jeff Rowland Concerto...
So Stereomojo picked as its ultimate winner the one Class D amd that TAS said doesn't even deserve a seat at the table. Goes to show...
The feedback we have regarding our amps is that they might not be the best choice for a horn speaker. That may extend to many of the other brands as well, but that is just my "best guess". So, you may want to proceed with caution. The sound of "digital" amps isn't for everyone.
I know this is a real novice question, but what exactly does class D mean, compared to Class A?
What type of amp is a Rotel 200 watt?
Bryston 4B SST?
Mac252 ?

I also here something about certain amps playing to a specific level at Class A, then A/B? What is this? What is A/B?

my nuforce ref 9 SEs are working just fine for me, powerful enough for my speakers, fast, detailed, clear as a bell, and no problems with emf for me, waiting for my nuforce p-9 preamp.
I'd like to comment on class d amps on horns. I'm using a tact Millenium MKIII amp on my Omega DUO's which is highly modded.
The tact is quite different than most other amps mentioned here. It directly convert's pcm tp PWM. It is incredibly quite and even at extreme low volumes doesn't lose resolution which is important when using + 100 db efficient speakers.
Class d amps switching a constant voltage on and off. The tact does the same. it differs because it is adjusting thje volate which is beeing swicthed. Very smart. no volumke control in the signal path?
A friend who has the same modded Millenium compared against the latest Nuforce and said with exception of the bass makes them sound broken in comparison especially in the heights.
Just my 2 cents
In response to class D amps running Horns.

I am running Channel Islands D200 with Klipsch LaScalas and find them to be the best amps I've yet heard with these horns.

I've had the LaScalas for over 20 years and run them with numerous other amps, and many with great success, but none sounded as good as the D200s.

I would suggest that not all class D amps are equal...
Adman227, I'm no expert on amplification classes, but my limited understanding goes something like this:

Class A: The output transistors don't switch off and so current is always flowing through the transistors. Whatever current is not demanded by the speakers remains as a voltage across the transistors. This difference between current flowing and voltage across the devices is why Class A amps generate significant heat and are considred particularly inefficient.

Class B: Each output transistor operates for half of the sound wave (one for positive and one for negative). In this way, the amplifier does not have current constantly flowing through the transistors but rather only has current flowing through it dependent on their being an input signal. Pure Class B amplifiers are rare in quality audio due to the crossover distortion which occurs due to the transistors not being constantly conducting current.

Class A/B: The solution to crossover distortion in Class B in a far more efficient package than Class A is the Class A/B amplifier which usually has the output transistors constantly conducting a very small current. So the amplifier operates in Class A for the first few watts (could be more could be less, depending on how the amplifier is biased) because the output transistors are constantly conducting a current. As output levels are increased, the amplifier then operates as a Class B with the transistors "sharing" the waveform.

Class D: Also known as "switching amplifiers", the Class D amplifiers output transistors are either fully on and conducting or fully off and not conducting. The Class D amplifiers are extremely efficient because when the output transistor is switched off, there is high voltage across the transistor but no current is conducted and vice-versa when the transistor is switched on there is current flowing but no voltage across the transistor. The switching on and off of the output transistors can cause "switching distortion", however.

So having just re-read all that, I'm not too sure I've helped clarify anything at all. I would think the amps you listed (Rotel, Bryston, etc) are all Class A/B types.

I respectfully request those scientists and electrical experts to correct my definitiona as neccessary!
Thank you "Hens" for taking the time to explain this is great detail. Much appreciated.
I have tried the Nuforce 9, the ps audio trio 100 and the sonic super t, and now the trends audio 10.1 with the michael mardis mods and I would have to say that with exception of horsepower these amps sound more the same than different. They are very clean, extremely fast, very efficient, and flat across the frequency band....but as yet they just don't ring my bell like a class tube amp can..I don't why, the emotional involvement is just not the same...what do you think?
Don't know who's best, but I prefer NuForce 9.02SEs to my old ARC VT100MKII - which sounded compressed by comparison. I prefer the dynamics and taut bass, smooth highs, nice mids of the NuForce. I have auditioned several other class D amps and they all sounded different from each other. YMMV. (I use an ARC tubed and modded pre for hopefully the best of both worlds. More here
That emotional uninvolvement was my initial reaction too. What caused that for me was the increased resolution. I was much more aware of the low level details which tended to distract me from just enjoying the music. Best way I can describe it is like going from a standard definition TV th HDTV. At first, I was so enthralled with the picture I was barely geting involved. I'd even watch stuff just because of the picture. Same with my class D.. at first. But now that I'm used to the detail, it doesn't distract me from the heart of the music and now it's much easier to be emotionally involved. It probably took about a month to get used to it. Don't think I can go back now. I really like being able to hear more clearly the finer details in the music.
I think you may have something about the resolution factor..you tend to listen to the sound and not the music..and I think the high resolution takes some of the mystery and romance out of the sound especially with us tube heads
I have found the better class D amps sound only as good as the front end supplying them. No where in my audio experience shown the old axiom so true, "Sh... in sh... out."

On my system even insulated cords, at any price range, invariably hash the music, slight as it may be.
And the high resolution enables one to listen at lower volume also,and still get plenty of impact.Turning it up louder and louder is un neccesary,although loud does sound quite good.
Hi, I have a few questions and comments for clarity.
Why not D for horns? I guess the mods for NuForce 9.02's have come through, delayed for too long for me to reconsider my past sale. (a ton of info after I packed them up; they do what? how's that good enough, fix due when?)
Lastly, what is meant by insulated cords?
and Who won the shoot-out, I didn't see the results in the MOJO page, though there was alot I intend to read.
Oh, not to forget. I find the comments elsewhere that these digital amps are immune to power cord changes to be as applicable to that of tube and s.s. amps. To say, in the case of Audio Magic, NuForce, and Edge... untrue! Not only do they show differences in cables, but one can make decisions regarding sound stage and clarity.
(Audio Metallurgy, Alicia Tweeks, Xyndack, Shunyata, Zu Mother2, Cardas, Aural Thrills, "Zen" and others were tried.)
Has anyone A/B'd the Edge g.5 to the Red wine?
I meant insulated ICs, and SCs impart noise onto the music signal. Most
recently I got to try Cardas Golden Reference, and Jena Labs. Neither were
acceptable, the Cardas being the worse.

On the contrary, the PCs should absolutely be double shielded. Even the
cheapest power cables, metal shielded throughout their length, are far better
than the most costly otherwise power cables. Shunyata is a good example.
Why not D for horns?
Despite someone "best guess" from my own experience JRDG Concerto + Tannoy 'Prestige' Glenair is an excellent combination=)...of course this is just my opinion...
i will respectfully disagree with the statement that insulated, (taken to mean shielded) ICs impart noise. No offense intended, but only a/b the same cable with and without the insulation could show that. Though, I do not doubt that you found Cardas and the other to be noisey. Shielding can
make for a blacker background, sending detail more forward (and that may be where the cable's hash existed); though some
will say it swallows the air a bit. The air (when it comes to cheap sounding cables) can be heard as noise itself. Your example of Shunyata
almost supports this, only in that you are removing the noise in the PC bia the field of the shielding. It must have been other factors that were
common to those two mentioned, that lead to your conclusion as it seems to be inopposition to the larger body of evidence regarding shielded vs
non-shielded cables. though again, I do not imply that the
observations were not actual.
You may find this humorous, that there are manu's claiming that "twisted pair" cables (a lesser form of reducing RF andEMI) so they use "Shielding"
to insulate (though shielding makes more of a sonic difference) that must be due to their using extremely thin wire and cheap connectors. Forgive me
if however, I have misinterpreted your meaning.
Spiro, There is absolutely no doubt in anyone's mind who have heard my
system concur IC insulation invariably imparts static into the signal. Bare
wire, or wire with just a thin sprayed coating don't. That is my system. The
Cardas was simply unlistenable. The Jena merely faired better.

Well shielded PCs are needed to defeat RFI emitted by the module. This RFI
will enter all other components that are not protected from it.

On the dielectric caused distortion, this may not be evident on some speaker
systems. If the preamp has excellent transparency as a great class D amp, a
very fine driver will pass the noise on. You can bank on it.
Great to see this post really had some legs.Still haven't made choice but seems like PS,Bel canto and from what i read hear Channel Island might be good switch for me.ut if I saty with high sensitivity I think that what I read from 6moons about the Redwine 30 or 70 mono's would be great.For $1500 more the 30 watt than the mono 70's at twice the price.If I get say a B&W Nautilus or other speaker that really needs the grunt they would be out.But again glad to see this thread has gotten soem liage from folks so you all must be interested and putting "Class D into the serch.Along with possibilities like expensive TacT and much more reasonable DEQX it's very "De Jure"
Okay, yes indeed! You are absolutely right. Air is the best insulator, teflon materials are next, but polypropes can be quite nasty. Shielding and insulating are not the same. Shielding is an insulation. I mistook your use of terms. I agree as my system shows what you describe regarding insulation. I find loose teflon to be nicer than the enamels I've tried, even light acrylics. Best regards. This thread has my mouth watering to hear the Red Wine unit.
Its new and just comming out, Nuforce ref 9 V2, here is the info from the Nuforce web site, if its anything like standard ref 9 to ref 9Se now that would be a very good thing. any older amp can be upgraded,

"V2 is a patented technology! Patent application 11/132,810 has been allowed (March, 2007) for issuance into a U.S. patent (will publish patent # as soon as it is available from the US Patent Office). The patent has been assigned to Nuforce, Inc.
V2 board has the same form factor as V1 board to facilitate upgrade of NuForce products."
Most experts agree that the perfection of Class D is a thing of the future (by true "high-end" definition/standards). With that said, I am very satisfied with the performance of the PS Audio GCC-250. It is VERY quit and to my ears is a definite improvement (although very subtle) in performance over my old AR-D240 (which was never an exceptional amp, but certainly not a bad sounding solid state either). With the GCC-250, bass is more controlled and there seems to be a bit less harshness in the highs. Additionally, there is a good bit of power on reserve for demanding musical passages. I like my music loud and I lean toward the classic rock, contemporary blues/jazz side of the spectrum and the GCC-250 does well with this genre. I do appreciate female vocals and acoustic guitar, which the GCC-250 also does a respectable job of reproducing. Bottom line: If you're looking for that true high-end experience stick with class A, class A/B (for now). However, the class D of today is pretty remarkable and there are some great amps available on the current market. While I have not compared many class D amps, I am very satisfied with what PS Audio has come up with in the form of the GCC-250. Note too that the GCC-100 has attained some very positive reviews.

I have just switched my Mardis modded Trend amp to battery power and to my ears, this is the best thing I have heard in a while. I just went down to Advance and bought one of those rechargable jumper battery packs for 59 bucks and plugged the amp into it. The difference in sound-staging and impact as well as noise floor reduction is amazing. I have always been a tube guy but this is the best solid state I have ever heard. I have previously owned the nuforce 9, ps audio trio, and the sonic t amp and this far exceeds those IMHO. You just have to try this to believe it...a total investment of 325 dollars for amp and battery. My ic's and speaker cable cost more. Has anybody else tried this yet?
Sanders ESL amplifier. Not class D but unique voltage amplifier. My D*200s packed up after 1 year, very disappointed! decided to give the Sanders a try while the D*200s were being repaired. Don't get me wrong, the D*200s were wonderful amps, but the Sanders is quite a step up the ladder - superb ability to handle transients, very powerful, dynamic and HF and midrange is one of the best I've heard from a SS amp. I have no affiliation with Sanders but want to share my experience with this new amplifier!
Just read a review at 6moons about a best of 2006 (or was it 2007) that is an Italian T amp manufacturer that has sm,all wood cube with a european roccoco type of cross or fleur or whatever that i find unique but hideous.but it is a quad channle that can be combined to two channel and puts out 120 watts with Battery feed (I think I remeber it being so-like the Redwine).Unfortunately it's not cheap being abouty price of two sets of redwine $3K 70 watt mono's.Also it seems that Larryx7 has come up with product that Vinnie at Redwine stopped making a modded Inpact T.I just wonder if the Trend put's out any more than the 6 eefective watts (after distortion iand other factors taken into conseideration the Impact and other 15 watt T's put out 6 watts meanning you need about about 8ohm's and 100 better 105.Might lite up some Zu speakers or a Klipsch and a very few others but it seems like it's nitch is in Apple Computers and other innexpensive consumer products and real world power is still expensive.Now if hey can make a 100 watts cost $500 with same sonic sttributes veryone talsk about we'd have a party!But I hope that in my main rig be it Class D,AB,A glass or module that I can affoird bedroom system of the Redwine 30 with it;'s own DACT and the modded Olive Muisc servers with HD's (and extra usb or thernet inputs),Wifi etc.Sounds like a nice sounding combo that can beam some tunes to a reciever mudule (maybe it works with Yamaha uits with small D units in them for muisc in the kitchen,bathrrom,or the closet (if you might be in one still).
I have a NuForce integrated with upgraded power supply (to 100 wpc) and upgraded to the V2 board. The V2 board appears to fix the RFI problem, which was very severe in my home. I had an early version of the integrated (I think) and when it was turned on, inexpensive FM radios were not usable for a radius far beyond 20 feet, more like 100 feet. Anyway, I think they made this better little by little over time in newer units, and with the V2 board I cannot detect any FM interference at all.

Also the V2 board does sound a little more extended on top and a little more detailed, while retaining the lovely liquid sound that NuForces seem to offer.

The combination of power upgrade and V2 board makes for a real nice sounding little power-house that is friendly to your neighbors FM radio (as far as I can tell).

I have had several chip amps including PS Audio, Nuforce, Trends, and just happened onto Channel Island VMB1 on audiogon with idea of a cheap second system. Boy was I surprised. I like it better that any of ones I have had. Go figure, only 40 watts but it sounds great.
Based on my experice with Bel Canto, Leviathon and Karma, the V2's of the NuForce amps have made a huge leap forward.

I have to say the Ref 9 SE V2 is one of the better amps I have every heard regardless of design.....
A couple of months ago I did a round of audition for amps to drive my Gallo Ref 3 II. I tried half a dozen of powerful amps in the $3,000-5,000 range, including the Bel Canto Ref 1000 (which I liked), but when I tried the NuForce SE9 v2 I immediately stopped searching: I found them head and shoulder above the competition and I brought them home
Whose got the best? Good luck in getting any sort of definite
answer. I am a believer in the Class D, T, Ice, Nuforce,etc. technology. I don't know who has the best or which technology is superior. I have an Audiosource Amp 7T I got off E-bay for a very modest sum. I am constantly surprised at how good it is. I will always have someone's "Class D" for my power amp.
I think this new Nuforce may really be a step up.I think we are in infancy of chip amps.I am surprised though given what I have read that another digital product hasn't caught fire that being the DEQX processor (I know I am hijacking my thread but it's so old it's growing whiskers).After reading the DEQX pre/pro review at (again) 6moons and hearing hub bub about NHT Xd I am surprise this digital domain fix hasn't gotten more licensing.But for speaker builders like a guy I know who put his own ribbons and Fostex into his own di-pole frames and put subs in floors he got to have x-over completely handled by DEQX which analyzes his room and components (including drives and "cabinet: which in his case is compressed foam) and he ols me it rocks.But then again he got it to do up a pair of $400 Dahlquist to sound almost as good as $10K Infinity MTS's.I think all this chip stuff from amps to room processing will make in 5 years the stereos we use look like Edison cylinder players.