The problem with Nuforce 9se and Class Ds as I've heard them
georgehifi -- Tue, 02/27/2007 - 01:22
Let me first reflect on some of the amps I've owned, pure classA transistor 150 watt water cooled built myself, numerous A/B transistors, numerous push/pull tube triode, ultralinear, and pentode, SE 805 triodes.
With all these amps I mainly owned for the exception of B&W 801's Electrostatic speakers not small but large ones ML Monolith, Acoustats numerous models.
With all these pieces of equipment over time I have never heard the type of strangeness in the upper mids/treble that I have heard with digital amps, not that it's harsh though some were, it's as though it is synthesized it gives you the fundamental all be it constricted, but the most un-nerving thing is there seems to be no harmonic structure to the music. The lower bass and upper bass is fine. I got the same experience from 5 different class D amps including the Nuforce 9 and 9se.
I now believe that digital has no place in high end audio at the moment, it is great bang for the buck, but for the moment should be regarded as midfi, good for subs and surround sound that has that much processing going on that it can be excused for not being Hi End.
I have no idea how the 9se won the amp of the year award or what ever it was, mabe the reviewer had a head cold or something , all I can say is that bang for buck value for money it is at the moment a great buy, do not place them in the same category as today's super amps that Absolute Sounds has raved about, because title, Absolute Sound, digital should no way be considered Absolute.
Cheers George
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Just to clarify, the idea of the absolute sound referred to in the title, The Absolute Sound, is -- in simple form -- that live music should be the reference used in judging equipment and recordings. That is live music is the absolute sound. By that criterion, all equipment (and recordings) fall short.
Personally, I have difficulty with the idea that the nuForce amps should not be praised because they "only" offer excellent value for money. Since the goal of this hobby is the enjoyment of music, I think the nuForce's are worthy of the highest praise. Only a small percentage of people can afford the equipment that comes the closest to reproducing the absolute sound.
I have no difficulty with the idea that certain qualities of products, like the treble of the nuForces, are more or less problematic for certain people and with certain equipment. On that basis, I can understand why you might not like the nuForce amps. I can also imagine many others who would absolutely love them.
CEO and Editorial Director, Nextscreen LLC
tmartin wrote:.
The Absolute Sound, is -- in simple form -- that live music should be the reference used in judging equipment and recordings. That is live music is the absolute sound. By that criterion, all equipment (and recordings) fall short.
Especially these amps
I have no difficulty with the idea that certain qualities of products, like the treble of the nuForces, are more or less problematic for certain people and with certain equipment.
Not just the treble but upper mids as well, that is clearly audible on a half decent system. And if you can't hear it, you don't deserve to call yourself audiophiles.
Personally, I have difficulty with the idea that the nuForce amps should not be praised because they "only" offer excellent value for money.
Here in Australia the Nuforce 9se cost $2800.00 a pair, there are many linear amps that surpass them in terms of sound quality at that price even cheaper, and they wouldn't get a mention in Absolute Sound even as a buget best buy, let alone Absolute Sounds AMP OF THE YEAR, what an Absolute Joke it got this status.
Cheers George
Sorry, but I don't agree with your broad generalization that all switching amps are incapable of realistic treble performance. IMO, any audio system that has trouble with all switching amps has not been optimized.
The NuForce amps use switching power supplies, and are notorious for generating enormous levels of radio frequency noise.
IME, RF noise is a serious problem when it gets into source components, and causes symptoms similar to those reported by some listeners in connection with surveys of switching amps. RF noise may also come from non-audio appliances such as DVRs and those with computer control, that also contain switching power supplies.
Starting with these facts, and the property of all switching amps that there must be a linear low-pass filter to keep the switching frequency tone out of the speakers, it is easy to see that all switching amps will have some level of switching tone (about 400 KHz in most implementations) in their output.
It is easy to understand that an audio system sensitive to RF noise in general will have trouble with any switching amp, as long as the switching tone can get into the source. It will likely have more trouble with those switching amps that use switching supplies. However, this is a property of the system and not of the amps.
Before I adopted switching amps, I used Class A tube and Class A/B solid-state amps in a hybrid bi-amp setup. Both types of amps were sensitive to RF noise on the speaker cables, and I got better sound by treating my cables to reduce their ability to support RF ringing.
I'm very happy with the treble from my switching amps, but then I've spent a lot of time reducing the RF sensitivities in my system.
Al Sekela wrote:
It is easy to understand that an audio system sensitive to RF noise in general will have trouble with any switching amp, as long as the switching tone can get into the source. It will likely have more trouble with those switching amps that use switching supplies. However, this is a property of the system and not of the amps.
Before I adopted switching amps, I used Class A tube and Class A/B solid-state amps in a hybrid bi-amp setup. Both types of amps were sensitive to RF noise on the speaker cables, and I got better sound by treating my cables to reduce their ability to support RF ringing.
I'm very happy with the treble from my switching amps, but then I've spent a lot of time reducing the RF sensitivities in my system.
Then you my friend have managed to solve the massive problem that the designers of these oscillators have not managed to accomplish.
It is a proven fact that the filtering has to be done in such a way that it effects the frequencies all the way down to the 10k region, and the harmonics of fundamentals all the way down to 5k and below.
Please give us your so called TREATMENT formula of cables that further enhances this filtering without stuffing up the harmonic structure of the upper two octaves (5k-20k) even more. And I'll show you Voodoo, or bad hearing.
Cheers George
Quote:
"It is a proven fact that the filtering has to be done in such a way that it effects the frequencies all the way down to the 10k region, and the harmonics of fundamentals all the way down to 5k and below."
You may think you know what you are talking about, but I assure you that you do not.
Al Sekela wrote:Quote
"It is a proven fact that the filtering has to be done in such a way that it effects the frequencies all the way down to the 10k region, and the harmonics of fundamentals all the way down to 5k and below."
You may think you know what you are talking about, but I assure you that you do not.
I'm afraid you do not, as the 2nd 3rd and 4th harmonics of a 5k fundamental extend out to 10k 20k and 40k we can probably leave the 40k out as far as cd replay is concerned but with analog include the 40k.
And where is your magic "TREATMENT" formula of your cable fix up for this problem, please explain. I call everything you think voodoo.
You cannot make a silk purse from a sows ear, another classic quote about Class D from Dan Agastino of Krell you can make mince meat from steak but you cannot reconstruct the mince meat back into steak
Cheers George
Please let us not go down the same route as CD, in that we lost everything above 20k because of the heavy brick wall filtering needed, good analog still sounds better in the higher octaves because cd has nothing above 20k plus a lot of phase shift down even lower because of it’s heavy filtering. But most all of us have learnt to live with this flaw in CD.
But with digital amps the problem goes even further down the music scale as they cannot yet design a brick wall filter that remove all the hash that digital amps produce at their outputs because of the power rating that the filters have to cope with 100-500watts, where in CD it’s only a couple of milliwatts. All they can do is low order filtering that can cope with the power at the output and so have to filter down even lower than CD has to, and such create the problem of cutting into the harmonic structure even more, and also causing even more phase shifts than CD has.
Look at the top Muso’s they tried digital and went back to their Soldarno, Marshall ect tubes and linear transistors.
Don’t let them (manufactures and & reviewers) dictate to us that we need to go down the same path that happened to CD’s, as we all may end up in the future to listening the high frequency dynamic bandwidth of AM radio with nothing in the way of harmonic structure above 5k.
It’s just a good money spinner for the manufacturers, as to build a digital amp of the Nuforce ilk costs peanuts in comparision good linear, we are talking in the order of 10% of the cost of good linear amps. Money Money Money to hell with good sound this is the end result with Class D.
Cheers George
George,
You like many others Keep knocking calss D amps
there are many mainstream manufatures has jump ship to class D
amps if what you say has any merits of not being true high end
how come Jeff Rowland (as regarded by many as true high end)
has jump ship to calss D he is not an Idiot.
Let me say one of my Friends who has Tannoy calasic Speakers
with Audio note conquest 300B amps and AN pre Kondo cables
IMHO could not match the midrange or topend of my system with NF 9SE,NF P9 WAR Dianne Speakers and Stealth indra cables this was not my conclusion its independent.
I also Challenge you for a blind test at the April Sydney Audiophile Society
Meeting to bring your best amplifier regardless of price so total group of people can make up their mind what they prefer not actualy seeing
whats playing this morning you decline to put your amps for shoot out
So George either put up or or shutup about class D amps
Pat O'Brien
Pat Obrien
Because it is 10x cheaper to make them. That is why ALL of the 'high-end' vendors jumped that wagon. Linear amps rule...
Now because the sound is mediocre compared to good quality linear amp (at the same price point) they need to justify their cost by bribing the magazines and their reviewers. Hype is their tool not sound quality. Same happened to CDs in 80s - they claimed that it is our ears that are not feeling the quality (that btw didn't exist in early CDs) - turntables were much better sounding but marketing is a powerful tool. Same happened with solid state amps in early 70s. Decades must pass before new technology matures are its limits are explored.
Profit margins when selling class D are much higher than well engineered class A, or class A/AB or class AB liner amps. I own pair of Quad 909s in my music room and they are amazing amps for 1000$ (on ebay or audiogon). No class D amp can sound like they do - they can be made by Jeff Rowland or whoever else.
I also have pair of linear Rotel 1050s power amps for my home theater set-up and they are much better sounding than Rotel's own new gen of class D amps they are promoting. Just ask when Quad, Krell, Pass Lab, Halcro, Parasound, Conrad-Johnson and other truly high end guys are going to switch - i believe never.
Last year's opinions may not be this year's answers.
Just because earlier generation D amps were supposedly sonically inferior doesn't mean that they are all damned forever.
As Chris Martins has written, class D amps are more speaker dependent (especially earlier iterations of the ICE circuit).
BTW you are free to keep your assumptions even if they deplete your wallet in the process... :)
Steven Stone
Contributor to The Absolute Sound, EnjoytheMusic.com, Vintage Guitar Magazine, and other fine publications
No Jeff is definatly not an idiot, he sees the massive profit margines that can be gained by having a digital amps in his stable, do you think for one micro second that he will drop his linear amps, no he going to cash in on the very high profits that can be had at the moment by the digital hysteria, and when it's over he will still have his linear amps to fall back on, wake up and smell the roses. The real proof will be if he is prepared to drop all his linear forever never to come back to them after every man Chinaman and his dog starts making digial amps at half or quarter the price of his, which will happen, then see where his loyalties lay.
And Pat you said this morning on the phone to me that your Nuforce 9se's (that you are the Aussie importer for) will give an exact replica of a 120k square wave from it's output that is fed into it's input from an audio generator, this is the biggest load of ---- I have ever heard, you would be lucky to get a 120k square wave to even come out of a digital amp with it's mandatory filtertng, yet without the filtering it may be possible, but it will be that corrupted with noise it wouldn't even resemble a square wave let alone a 120k square wave.
I asked you to send me one channel only and I will take picks of it trying to do a 120k square wave on my very quick Tektronix gear and you will see, and I will post them here on this site, but you declined.
I had all my gear at the last months meeting but you only come once a year. But I am bringing linear amps of lower quality than mine own, at the same price of the NF 9se's $3k or are they $5k, doesn't matter the $3K linears will do the trick for the digital V Linear shootout, you don't need 10k amps to blow away these digital oscillators $3K should do nicely, you should have consulted the organizing commity before blowing off that statement.
As you can see, there is nothing to put up or shut up about Pat, your the one who feels threatened not me, because every time these Nuforces 8's 9's or 9se's have been demonstrated at our Audio meetings they have been easily beaten every time.
Cheers George
George
How gulable are you I said Nuforce amp will do 125Khz S/vave
but never said the model so you assume it was Ref9SE
I'll put it straight its the P9 acording to you every one should scrap all classD amps before I foget every pre amp as well because according to you
your passive light speed has no peer. common George bring your best
amp I dont want any excusees after so put up or shut up by the way
Rowland needs to sell one of his class amp amake lot more money than selling class Damps so even there you are WRONG
cheers
Pat O'brien
Pat Obrien
PJO wrote:George
How gulable are you I said Nuforce amp will do 125Khz S/vave
but never said the model so you assume it was Ref9SE
Pat O'brien
Now you are the one who as back pedalled, that is the shoot out, Edgar Kramers from 6 Moons 9se V a Linear amp as told to me by our club President, and you WERE refering to the 9se as this is what this whole thread is about and it's unjustifed award,
As for starting to attack other aspects of my life this was expected from you as you have little technical amplifier knowledge which is dangerous for you as shown by sprouting off about 120k square waves from the Nufore 9se, and all your able to do is to digress now to something else like my "Lightspeed Attenuator", please get the name right and thanks for the plug.
http//www.diyaudio.com/forums/showthread.php?s=&threadid=80194
As for now mentioning a P9 I have no idea what it is, and If it is digital I don't want to know, you can stick it were the sun don't shine.
BTW just found out the P9 is a fully LINEAR PREAMP by Nuforce and it has nothing to do with Digital or SMP supplies, the shootout is between Digital Amps/SMP V Linear Amps, know your product!
Love and kisses George
George,
You are the one who is attacking every one who likes class D sound
as having to have their heads examined or having colds or profiteering
thats not me you have never heard Nuforce or Belcanto amps extensivly
other than brief listen at HI fi meetings you have made of your mind
about class D as crap only way to proove is to have a blind test so People at the meeting can decide what they prefer. as I said before put up or shutup by the way what qualifications do you have at least I have electrical and electronics Qualifications to backup so I should not no any thing about electronics be idustrial or comercial.
Finnaly this is all about advancing enjoyment of listening to music
via any type of tool that helps you to get there.
one last comment yours and my friend and President of Audio sociaty of Sydney who has the best sound in Sydney that I've heard owns Halcro DM68, Elsen valve mono blocks also owns Bel canto Ref1000 mono blocks and he says BC are equal and some days better than the others is he got bad hearing? I dont think so.
so Please George dont bag class D Put up or shutup
lots of love
Pat Obrien
Pat Obrien
I've already put up Pat, you are the one trying to make $ out of Class D not me.
And Richard Wong our President got rid of his Nuforce amps and it won't be long before the Belcanto digitals go, because they are as he says just for hot Summer days because the Halcro's and the Elson "Cymer" single ended tube amps heat up his non ventilated listening room too much during hot summer days, otherwise he would rather listen to the Halcro's and the single ended tubes. That is from the horses mouth our illustrious President.
So YOU shut up or put up.
George here you go again
You told half truths about ASON Presidents wishes he has no intetion of
getting rid of his BC Ref1000 He does use it in summer and winter
uses in summer more as it would generate little heat but the main reason
is that its sounds good so tell me George whats wrong with his hearing
you keep back peddling when I say to put up you have been telling
people that your ME850 modified by you is the best that you have heard so lets go ahead to ahead ME vs NF so we dont have to go through this crap you carry on about For the $ I make visit my website so you can see
why I have Electrical Engineering Co. so again You are wrong
Pat Obrien
There you go again trying to change the main subject matter.
I'm not buying into this off subject crap and mud slinging anymore, you have a armature rewind company, and you import some audio products, WOW, that does not give you one iota of credibilty for amplifier electronic design or manufacturing, unlike myself who's built my own designs for the last 40 years, tube and transistor.
All will be reviled in the "Class D" V "Linear" Shootout at the end of April and I'll make sure it's all posted here.
Cheers George
George,
Finaly I'm getting through to you so we are on for
George ME850 vs NF9SE
Looking forward to this.
George by the way we have two Companys one WA Rewind Co and
SEME Electrical Engineering Co combine workforce of 90people so you are wrong again I built my own amp including making my circuit boards in 1975 and that I still have today I never was into building Valves except for few V/pre amps.
Pat Obrien
Here is somthing for Georgehifi
@Audiogon discussion Karma vs NF9se
03-20-07: Vicdamone
I've had both in my home driving Avalon Acoustics Eidolons. These speakers are considered by some to be a difficult load but I still own a 60 watt tube amplifier that can drive them nicely.
The Kharma and the SE are both fine examples of class D design. In my system the Kharma had a more designed and refined presentation where the NuForce was more transparent balls to the wall. Both are musical to me. While their sonic differences are definitely a matter of taste I wouldn't consider one superior to the other.
As far as their ability to drive my speakers the Kharmas ran out of steam first but at a level I don't think anybody would realistically listen at. An often overlooked quality of class D amplifiers is their ability to play loud without fatigue. They both had more fatigue free gain than my, even more powerful, linear solid state amplifier.
Vicdamone (System | Threads | Answers)
Pat Obrien
i sure will be looking for the results of the shoot out, as for my self i love my nuforce ref 9 ses. they have no problems driving my speakers, and i love the sound that i am getting. :D
its the music that counts
beachbum wrote:i sure will be looking for the results of the shoot out, as for my self i love my nuforce ref 9 ses. they have no problems driving my speakers, and i love the sound that i am getting. D
I am sorry to say there will be no shootout, as the Nuforce party will not demo the 9se now unless is it driven by the new p9 preamp and using their interconnects and shielded speaker wire.
The Linear amp party wanted to have 3rd party speakers, preamp, interconnects and speaker cable, this was the only fair way of a proper shootout between Class D V Linear amplifiers, unfortunately this could not be met by the Class D party,
We will in the future be able to get the Nuforce hopefully from a private owner and similar Class D's from other owners to conduct a proper ClassD V Linear amplifier shootout with all 3rd party peripherals (speakers, preamp & cables), so it can be conducted fairly.
(watch this space)
Cheers George
What a load of crock
Remember this topic started as class D amps could not sound any good
regardless inherently flawed as claimed by George hifi.
George pulled out as we were going to use NF p9 and our own cables
George was allowed to use what ever he wishes in his setup
so I leave it to you's to come to your own conclusions.
if the the class D amps are inherently flawed it shoulldn't matter
what you use with'em they simply can't sound any good(Ghifi) or can it?
Cheers
Pat
NF distributor :
Pat Obrien
PJO wrote:
George pulled out as we were going to use NF p9 and our own cables
George was allowed to use what ever he wishes in his setup
How can you possibly have an A/B comparison between Class D and Linear amps when all the peripherals are different.
Our President had all third party Hovland preamp, Audioquest cables and Ref3a speakers lined up for this shootout, it was you Pat that refused to use these third party products, and I'm glad you have admitted it.
So I leave it up to the to the members of this forum to form their own conclusion on what transpired. As I said it will be done properly in the future and I will publish the results.
Cheers George
As you said Class D is crap and the reviewers had head colds class D can never sound good regardless this is your words.
So why are you worried about going head to head against Nuforce
according to you less than $1000.00 NAd will crap on it so why not
stand up to your own believe's. this shoot is all about whether Class D
can sound good or not. I only got involved when you started the post
bagging NF. I would like to see some responses from others in this forum
Pat Obrien
Waffel, waffel, waffel, are these the sounds of a sinking ship? ?
Sounds like it to me.
Cheers George
Since many of us have experienced synergistic and non-synergistic equipment combos, why not try the test with both sets of ancillary gear?
CEO and Editorial Director, Nextscreen LLC
Waffel,Waffel, waffel, you are right this is your waffel
Let me first reflect on some of the amps I've owned, pure classA transistor 150 watt water cooled built myself, numerous A/B transistors, numerous push/pull tube triode, ultralinear, and pentode, SE 805 triodes.
With all these amps I mainly owned for the exception of B&W 801's Electrostatic speakers not small but large ones ML Monolith, Acoustats numerous models.
With all these pieces of equipment over time I have never heard the type of strangeness in the upper mids/treble that I have heard with digital amps, not that it's harsh though some were, it's as though it is synthesized it gives you the fundamental all be it constricted, but the most un-nerving thing is there seems to be no harmonic structure to the music. The lower bass and upper bass is fine. I got the same experience from 5 different class D amps including the Nuforce 9 and 9se.
I now believe that digital has no place in high end audio at the moment, it is great bang for the buck, but for the moment should be regarded as midfi, good for subs and surround sound that has that much processing going on that it can be excused for not being Hi End.
I have no idea how the 9se won the amp of the year award or what ever it was, mabe the reviewer had a head cold or something , all I can say is that bang for buck value for money it is at the moment a great buy, do not place them in the same category as today's super amps that Absolute Sounds has raved about, because title, Absolute Sound, digital should no way be considered Absolute.
as Tmartin says its all about system synergy not one technology.if your
theory is correct we all be watching BW tvs
as far as I'm concern you fail to put up so I ask you politely to stop
making silly comments.
Pat Obrien
Waffle, waffle, waffle,
I suppose you guys all jumped straight into VHS to forsake Beta.
I suppose you guys all jumped straight into CD to forsake analogue.
And you are the guys that will try to do it to Linear as well, but not if I can help it, as many of us have learnt our lesson from those days of VHS and CD not to jump the gun anymore, especially with these digital amps ( or should I say oscillators).
Once again Class D has no place in highend stereo, leave it for subwoofers and surround sound applications, where there is so much processing going on that the harmonics and passion of the music has been stripped away anyway so it does not matter.
I still love you Pat even if you do have cloth ears. wink
Cheers George
Didn't I say to stop making silly comments.?
last one was very very very silly
I love you too
Pat Obrien
hello its been a while since my last visit.
I have added a nuforce p-9 pre amp to my ref 9 se
its been in my system for a little over two weeks.
i have to say that the combo is a match made in heaven arrangement.
the p-9 is ultra quite, fast, holographic, and very resolving.
the next best thing is nuforces policy of updating there gear.
V 2 is the next version of nuforce amps.
according to the web site the issue of rf is a non issue.
i dont know many audio manufacturers who offer upgrades to
gear already in use. what a breath of fresh air nuforce has brought
to the audio community.
they gave me full trade in from p8 to p9.
they offered the se upgrade for my ref 9s.
i am sorry that the discussion above is taking place.
anyone who knocks class d technology is either not a audiophile
or just plan out of it IMHO
If you do a web search for nuforce amps its heavily infaver of the
positives of class d. most have traded in there amps for class d.
if any of you are ever in the New Orleans area get in touch and drop in for a audition.
its the music that counts
I was not able to find the statement you mentioned on the Nuforce web site, but one of their rotating photo displays shows the new power supply for the Reference 9, located in one corner of the amplifier circuit board.
This means the noise from the power supply is not isolated at all from the amplifier. Since they use a form of audio feedback in the amplifier control, I don't see how they keep the power supply noise from affecting the audio output.
al check the audiocircle web site, there is a nuforce manufacturers forum area. i might have seen it there,
its the music that counts
I have used many amps, tubes and ss, driving my AVI Brio speakers and currently using the nuforce 9V2 monos and really love the sound coming from them, especially the details are so much easier to hear and at the same time everything sounds smoother that ever before. My AVI's are capable to produce very high resolution bass (12" Volt Radial in sealed enclosure), the nuforce takes advantage of this as I have never heard before with other amps I had. I also tried some UcD based amps which where also very very good, I took the Nuforce but that's a matter of taste I guess. Speaker matching is just as important as with other amps as with class-d amps. In general I can say that it would be really stupid if people say that class-d isn't 'high-end', those who claim that I think should consider to trade-in their Bose speakers.
I have a pair of Wilson Benesch Bishop speakers, being driven by a pair of Nuforce Ref 9V2 SE amps, with a Sonic Frontiers Line 3 SE+ preamp and an Esoteric DV50s SACD/CD player. My analog front end is a JA Michell Orbe, Wilson Benesch ACT 2.0 tonearm, Ortofon Jubilee cartridge, and a Balanced Audio Technology VK-P10 SE phono stage.
Let me say, without ANY reservations, that these little amps are simply astoundingly good! They are driving nine 6" bass/midrange speakers and one tweeter in each speaker cabinet without any effort at all and, in addition to the speed and control that they have in the bass and mid-range (which is phenominal..), they have a tremendous sense of ease, air, speed, and clarity in the treble. They are easily as good as the Wolcott P220M tube monoblocks that they replaced and I have had no problems at all with any digital noise or other interference when using them with the Sonic Frontiers Line 3 SE, a tube preamp that was designed and built way before digital amps came onto the scene or with the BAT VK-P10 SE, a tube phono stage that is amplifying a 0.34 mV (!) output from the Ortofon Jubilee. I am extremely happy with them and it is no wonder that these amps have taken the audio press by storm! True giant killers that can be compared to other amps of any price.
Hi MarkSA,
What cables, interconnects, speaker cables and power cords do you use in your system? Don't you hear a brightness in the treble, due to speaker-amplifier character? Is the sound full bodied?
I've just found this rather old thread and find it interesting. My musical enjoyment has followed an interesting path over the years. I started with a Hafler SS amp as a student and then spent a long time with valves - Dyna Stereo 70 and Music Reference RM-9. I then moved to active with Avantgarde Solos (Class a/b solid state) and now use ADAM Tensor actives. Each step has led the sound closer to my preference: detail, dynamics and non-fatiguing listening. The ADAMs have ICE power PWM amps for midrange and bass but Class a/b for treble. Active gets around the amp/speaker matching issue for the end user as it becomes the manufacturer's issue so it suits me - more time to listen to the music. It's telling though that ADAM don't use ICE amps for the treble X-ART driver although they are happy to do it for the midrange and bass. The speakers have a very natural and non-fatiguing treble but I wonder if that would have been the case if they'd used a PWM amp there. The midrange is very detailed and non-fatiguing though and that is PWM powered. maybe an advantage of active is the ability to use the best amplification method for the driver and use an amp design where it's strengths lay - certainly in this case there's a good case made for PWM amps in a high-end system.
Came to this thread late as well. Seems to be very prominent on Google!! With respect, Georgehifi, CD is not perfect, so I suppose the RIAA eq curve is?? As to switching amps, I suggest blind testing is the only valid way to assess components, I'm sure we will be very surprised when our assessment is not influenced by price, rarity, exoticness, technical mumbojumbo, reviews, etc. I think there will be a lot of red faces amongst the most vociferous of critics after such a session, hence the declared abhorrence of the practice. I am extremely critical of alternative medicine, making claims on anecdote, or experience, and for not submitting to rigorous scientific testing, why should I be prepared to accept such unscientific practice from the audiophile world? The only reason to deny scientific trial is if there is a lot of deception and perhaps fraud involved.Personally, I am amazed at the quality of the of the sound of the nuforce amps.
George, even Analog had its growing pains... decades after its introduction we still unmasking layers of distortion. Class D, in terms of length of time has had one of the most aggressive and lustrious (shortest period) of development from non audiophile to audiophile... NuForce has indeed been aware of the harmonic realities of the technology and have been improving with every iteration of their amps... i am not convinced that they have solved fully the upper harmonic issues, but from the lower octaves into upper midbass - i would put them up against the best. So my issue is not necessarily your concern, but the dis-ingenuous mannerisms that you've expressed in this thread... especially the way in which you have discarded that Audiophile-reality of SYSTEM SYNERGY. As for [Oldears] post above - on blind listening... i ask: Isn't the listener's taste an unscientific variable in the process of listening?