How far have ss amps really come in the last twenty years?

I've spent 50 years or so as a professional musician in different bands, although in recent years I'm far more likely to gig playing solo acoustic (still play electric often), and to say "You stated you were in a band, so I believe your ears are shot" is ridiculous. Are the great long-term working recording mastering technicians in that boat? Ear issues will arise more likely with some musicians, but not all, and the ability to have excellent taste and an ear for what's right that develops over years of experience is something I cash in on often as a live sound mixer/technician, even though some tinnitus and inability to hear a dog whistle may be limiting somewhere. Also note that inna is here to win...hmmm....I think all well designed amps SHOULD sound somewhat similar as they're supposed to be replicating whatever goes into them as accurately as possible, with the subjective tastes of the listener finding what minor tone and coherency schemes fit them best...for me it involves tubes since they seem to get at the life in instruments more readily, or an early wind up gramophone could be great for lower arm exercise which has zero to do with this topic but I tossed it in anyway.

as for the insight on amps have reached their zenith, and or are all alike now, well, that is pure nonsense.

neither are they indistinguishably similar in build, they are different sonically as well.

just my input, mind you, but I trust my ears and hear distinct diffs from many amps and preamps when both are of the same brand or house sound, or as separates which has been my usual path for building a system.

naturally the only true way to ensure or prove positive once and for all, would be to have several amp makers gear set onto the same brand rack with the same source device and roll them into a room with a pair of speakers which have been optimized for that room and play them all one after the other off a set playlist.

this scenario ain’t ever gonna happen.

another way to get the evidence all amps are not equal is to buy some and listen for yourself.

this I have done along with so many, many others and found out as said, amps are NOT all alike or even too close to call sonically, not even SS amps regardless their classifications.

its ridiculous to believe they are!

of course for those who actually do believe amps are more alike than not, it is sure gonna be a cheaper and shorter path to their audio Nirvana.

they could simply buy a Bose setup and be done.

on this topic….
to get deeper insight or just some texture, on amplifier innovation, design, and concepts this link reveals an article which addresses major amp icons thru the years and those people responsible for them.

https://www.theabsolutesound.com/articles/the-12-most-significant-power-amplifiers-of-all-time/

I found the most interesting part the time frames for these designs many which date well back into the 20th century, and how ground breaking many of these products have stood the test of popularity and time together, remaining viable and often sought after products even in today’s market.

until we see plasma conduits carrying anti matter fueled power supplies, or photonic signal converters or the like amps aren’t going to see much of a complete face lift in the near future.

what role will amps play when the sOTA finally arrives at life size Hallograms in the home?

someone is gonna have to figure out how to get point source audio info from every axis within that setting to coincide with the visibly displayed content… and I think we’re back to converting electrical signals into and back from photonic means.

the curren optical fiber conduit merely carries a signal, it does not develop or manipulate it what so ever, it is just another kind of wire or pipe information passes thru and nothing more.

to accomplish it, will take a new kind of ‘wheel’..

I am sorry, but neither Pass nor Curl can compete at the top level. Perhaps they are doing something wrong.

:)  Nelson's SIT amplifiers are some of the best sounding out there. But they are only available in kit form IIRC. SITs went out of production a long time ago.

Regarding John Curl, isn't he the one behind the Blowtorch preamp? That is one of the very few solid state preamps that has developed a legendary status.

Distortion is an interesting term. Distortion compared to what? You mention that the human ear treats 2nd and 3rd harmonic distortion favorably. Therefore, one needs to question whether these distortions are distortions at all. Since we, as humans are using our ear/brain to determine what is considered as a true  and pure signal, wouldn’t it make more sense to label a signal that doesn’t include these 2nd and 3rd harmonics as the signal that is actually distorted...?

Even though they are beneficial in many ways they are still distortions. This is why there is that term 'euphonic'. I've often felt though that distortion harmonics should be weighted according to how important and audible they are to the ear.

It was a sign of the times that Curl et all went to Parasound about 20 years ago and abondonded Blowtorch preamp and the Bar B Q amp which were very high end components. I participated with Curl and Crump (TG Audio) the last year they exhibited the BAR B Q with the Blowtorch. The following year 2001 the JC-1 (scaled down Bar B Q) debuted with Blowtorch and Entec Number Cruncher DAC. I isolated the Blowtorch, Entec and four (count em!) JC-1s that year with a one of a kind double decker Nimbus and four Promethean isolation bases.

I suspect that just like loudspeakers, when the amplifier designer engineers an amplifier to fit to a certain price point, he is also targeting an amplifier sound that he thinks best presents music as realistically as possible.  In other words, its not all about perfect square waves, SNR and THD.  Therefore, its reasonable to expect that different designers have different ideas of what sounds right...hence amplifier will sound different.

As Blindjim said....just try a few amps and it doesn't take long to see that either the amps themselves sound different....or the way they interact with the rest of the equipment results in a different sound.

Right now, I'm "trying out" a new amplifier called the 2Cherry from Digital Amplifier Company. Its class d, no modules, all in house designed circuitry using discrete components...and boy does it sound good...open, three dimensional, detailed, liquid...I could go on....for less than $3k....so I think there may well be room for continued amplifier development.

And in a way, I agree with Atmasphere...most of us say that we want as little distortion as possible...but I think we really want is what sounds the most like trumpets, pianos, guitars and voices that we have heard live...and maybe sometimes, to some listeners, a euphonic presentation is more pleasing.

Which component is further along? Speakers or Amps? Would the best speaker, cost no object, in the world show any shortcomings of the best, cost no object, amplifier in the world? Or vise versa? 

Alan Shaw would say there is very little new in amplifiers. Indeed, amplification technology is widely used and optimized for many purposes, not just audio, and is more or less a "solved" problem. For those of you who haven’t had the pleasure, this thread will show you some of his thinking. https://www.harbeth.co.uk/usergroup/forum/subjective-soundings-your-views-on-audio/electronics-sources-stands-cables-accessories/amplifier-discussion/2390-the-last-words-on-audio-amplifiers-jan-2015

And if you disagree, and can prove an audible difference under his conditions (gain matching), he's offering a pair of his top-of-the-line speakers (see the first few posts).  

And if you disagree, and can prove an audible difference under his conditions (gain matching), he's offering a pair of his top-of-the-line speakers (see the first few posts).  

That sounds nice. Might run short on speakers after a while...

Like shooting fish in a barrel. Do you have to fly to England to do the shootout?

I will take this challenge. It would be difficult for me, or anyone for that matter, to convince anyone else that differences are heard, unless they heard it too. If I were doing the amp comparison through my own system, in my own room, with my own selected music, I would, and have, each and every time, hear differences. Mr. Shaw seems to say, if the circuit is the same, distortions are kept at a minimum, impedances match, and the amps are working comfortably within their limits, the 10K amp, with all of it's better parts, more heavy duty chassis, larger power supply, etc., will not sound better, or even different. Wow, is all I can say, if I read, and interpreted correctly, all that I read. Does this mean Harbeth speakers use inexpensive crossover components, because Mr. Shaw hears no difference in better capacitors, etc ? As far as a system I am not familiar with ( different equipment, room, etc. ) ? As long as I am given enough time to listen and evaluate this system, using my own selected music, sign me up ! Enjoy ! MrD.

Excellent. Let us all know how it goes!  In fact, if you do succeed, it will certainly be worth a write-up in the audio publication of your choosing.

wolf, I had no idea if roberjerman was in a band, nor am I claiming hearing loss of any band members, as I was a singer in a band. But for someone as he, to claim, differences in amplifiers do not exist ( and to have a " collection " of them ), must have listening or hearing issues, or systems not hi def enough to notice. Tell me your Schiit pre and Had amp does not sound better ( if not better, at least different ) than your previous gear ( you bought this gear before the Heresy 111s ). Differences exist, and that is all. Enjoy ! MrD.

Ahofer, set it up for me with Shaw, and I will do it, no problem. I am sorry if you feel I do not agree with my interpretation of what I just read. By your response, I am not sure you hear differences in amplification, not even to determine if one is more to your liking over another. Obviously, Shaw makes a fine line of loudspeakers, but I still found it a bit surprising. I can also tell you, many others here would take the challenge, as Atmosphere pointed out, coming home with a new set of speakers. Always, and Enjoy ! MrD.

I am not a fan of Harbeth speakers so it is not surprising that I wouldnt agree with his take on many things audio. 

@mrdecibel  What a strange request!  I don't know him any better than you, but he's quite available in those forums.  Sounds like you aren't completely serious.  Set it up yourself.

I'll do you one better - I'll bet you another grand ($1000) even odds you will fail (you wouldn't have to pay if you can't agree on set up).  But only you can negotiate the terms with Alan.  Maybe at the next expo where there's a Harbeth booth.

No, in my limited experience, I often don't hear the difference between amplifiers (with the exception of underpowered or tube-bloated amps), and I resent it when someone tries to convince me that the new power supply they just swapped in makes any perceptible difference at all.  I sort of want there to be a difference in my heart (I own some expensive gear), but given a review of the actual evidence, I'd have to *bet* that 95% of the people on this forum, and of the dealers I've met, couldn't pass a properly constructed blind or ABX test  (to a reasonable confidence level) of level-matched, properly-powered amplifiers. I may be missing something (point it out to me), but there's almost no convincing evidence out there to support repeatably audible differences between high quality cables or amps (I assume this list is reasonably complete - https://www.head-fi.org/threads/testing-audiophile-claims-and-myths.486598/ ).  The only people who claim to have done this consistently seem to have been by themselves when it happened.  In fact, there's only scant evidence that audiophiles can tell the difference between levels of digital resolution (and I have an extensive hi-res collection!!).  See Archimago's repeated tests -  https://archimago.blogspot.com/   

This is unpleasant stuff to acknowledge about ourselves, but I don't think the hobby does itself any favors by wishing it away.  Let's disprove or confirm it!  Nothing to lose and everything to gain.

So I'm in the enviable position of both being willing to bet, and kind of hoping I lose.

https://www.dagogo.com/audio-by-van-alstine-abx-comparator-review-part-1-audio-store-wiring/

This reviewer had a difficult time differentiating between amps when level matched 

Folks, while I very much like my high powered Jeff Rowland ss amp, it really isn’t as resolving as the Jadis tube mono blocks that I use as my main amplification source. The two amps sound pretty different, and are a different ‘flavor’...easy to hear. I suspect those that don’t believe that amps sound different, one to the other, really don’t have enough of a resolving system to hear the differences.(and no, it is more than volume matching, as I am able to do this with exactitude in my system).

Where I think amps have advanced the most are in the realm of modestly priced amps. Expensive amps 20 years ago already sounded excellent but budget amps 20 years ago never let you forget they were budget amps. It’s in this area where I think great strides have been made 

@maplegrovemusic  yes, I read through all of that some time ago. He claims to have gone 7/8 and 8/8 on other comparisons, but I don't think he bothered to have it witnessed, did he?  That suspicion aside, I admire his willingness to execute the tests and try not to rationalize the results away.

 @zavato  I think your post would seem to be very correct..although I think it applies perhaps a little more to ss amps than tube. For example, I think the new KT 120 and KT150’s are a superior sounding tube to the old KT88’s and 6550’s utilized by most manufacturers.

ahofer, Maybe we can get together, at my home, using my system, with me blindfolded, and you change out a few amplifiers of your choosing. I will want a 3rd party here. I believe you have stated in other posts of yours, that you do hear differences between some digital gear, which is interesting to me, because our ears only respond to the analog portion of digital gear, as we cannot hear " 0s " and " 1s ". Listen, I get it. You do not hear differences, so, you feel they do not exist. That is fine, and unfortunate. I do not need to convince you, or anyone, of anything. I am generally a lone listener, and I am in this hobby for myself. I am in Central Florida if you ever want to arrange something. I have 20 or so amplifiers here, and you are welcome to bring anything you have. My last statement, however is this. In this hobby, you are in the minority of listeners that do not hear differences in amplifiers. And yes, I have changed out capacitors ( tremendous in speakers, too ), enlarged power supplies ( well actually a tech friend ), and for years, have changed out power cords, on products that were available before IEC inlets, with differences in sq, and usually, for the better. And I do need to ask this. If you do own very expensive gear, and admit you do not hear differences, why do you own such expensive gear ? I know you are a wall street guy, so maybe it is because of prestige. You tell me. Enjoy ! MrD.

@mrdecibel

My interest in this is about the tension between my subjective and objective self, really. I’ve enjoyed the equipment I’ve owned (although I don’t upgrade nearly as much as the average audiophile) and that’s enough for me. Unfortunately, being an audiophile is negative status, if anything, in my part of finance. Exotic athletic achievements, massive watches, and ultra-casual seem to be the thing now.

It is indeed possible my hearing is shot. I’ve played in big bands and attend concerts every two weeks, as well as ride the subway daily.

I actually want to know if Shaw is right or wrong, whether my subjective impressions overcome or create the illusion of audible differences. The subjectivists have done a very poor job of proving him, and his ilk, wrong after 30 years, but I’m not entirely convinced yet. I want one of you guys to go for it, or go for it elsewhere - level matched, properly controlled. Or maybe you have and I haven’t seen it.

One thing that is important in my line of work - separating objective observations against your feelings. If you can maintain allegiance to the former in difficult times you can make a lot of money. I’m lucky enough to have been successful at that a few times (and less successful a few other times).

Now I observe that despite nearly $20k of available inducement, you won’t try to back up your assertions. I really don’t mean this to be snarky, but shouldn’t I view that as revealing?

@mrdecibel

I'm with you...amplifier differences are audible.  Holy Moly...20 amplifiers, why so many?  Which ones are your favorites?

ahofer, I appreciate your response. Listen, I am a simple guy, but very complex when it concerns audio gear, and more importantly, music listening. I know what I know, I hear what I hear, and, there are so many of us, as I am not a lone exception. Continue on your path of discovery, as I have been there for a very long time. Always, and Enjoy ! MrD.

snapsc, I was an amplifier junkie ( I suppose I still am ), that is why. A few years ago I had quite a bit more, but sold off many, much more of them higher end. Here is a list of what I still have, not in any order. Hafler DH 200, DH 220, DH 500, (2)XL 280, Citation 12, Citation 12 with conversion of Pass Circuit, Citation 16A, Marantz model 15, Soundcraftsmen PCR 800, A 5002, A 400, Smart Theater Systems TA 242, Crown PS 400, Rotel RB 850, Adcom GFA 535 series 2, Yamaha P 2050, P 2075, P 2160, P 2200, (2)Nuforce STA 200, ADA PF 201, PF 2501 ( my current favorite ). I might have left out one or two, as some are still in closets. My favorite amp of all time ( that did it all for me ), was the Krell KSA 50. Enjoy ! MrD.

the most important thing of all, I’ve come to find in over 30 years of looking at the technical side and the esoteric side and then flipping for another side and looking at how enjoyable the music is and how ’natural’ it is presented....

..well..the most important thing to come about is the return to what Sony did.

Which is the ’linear gain curve transistor’. In the case of Sony, the V-Fet transistor.
That’s it. nothing else matters. Just that.

Everything else is literally like trying to make rulers and measurement devices out of mold infested mud on crack.

If one is not pursuing or trying to get the V-Fet transistor (small and large signal) manufacturing process up and going, and to issue amplifiers on that vector, then IMO, one is just following market demands.

Demands which are based on ignorance. Based on lack of exposure to V-fet and linear gain in transistors... and then being ’normalized’ into thinking that BJT and FET transistors are actually doing anything that sounds like music.

The reality, unrealized, unheard and not compared...is that..THEY ARE NOT.

This was noted by a few in the late 70’s and early 80’s..but...the then emergent FET transistor manufacturing process was so much cheaper..that V-Fet died off. And the actual direction forward..was lost. We wanted peaks and the demand and desires of the middle of the bell curve ..threw it away..as they did not know what they had in hand. Money and desires for financial success..threw the way forward..into the trashcan. V-fet was too expensive. The fanfare for the common man shot the pursuit of the best...in the face... and buried it face down in a shallow grave. And no one noticed.

~~~~~~~~~~~~~~~

I keep wanting to buy a new amplifier or try this or that technique in mods and such..but then..I realize again, that it is not V-fet ...and that I’m trying to move forward here..and if it’s not V-Fet ..then, I’m wasting my time. As the effort will be wasted on inferior technology, where the inferior technology all (every last transistor) misses a critical difference, where that critical difference is on a different plateau.

It’s all a circular dead end, when it is compared directly to V-Fet (on any basis).

That - there is another path.
The only thing worth pursuing when searching for the peak of audio, is V-Fets and tubes. The rest is limited by what it is. Which is..inferior in the most critical aspect. No emergent transistor technology, like Gan or class D or class D via GAN... can do this simple, fundamental, utterly critical thing..which is one of: linear gain.

I may be missing something (point it out to me), but there’s almost no convincing evidence out there to support repeatably audible differences between high quality cables or amps

The differences have to do with distortion. This is easy to measure, and when measurement correlates with subjective experience then we can call it real. Its well-known that IMD is highly audible. It should then come as no surprise that when adding capacitance to a power supply reduces IMD (due to less modulation of the power supply- this is a simple timing constant in most cases so this is easy to quantify) that you can also hear it.

The higher ordered harmonics have long been known to contribute to brightness and harshness. We’ve known this since the 1930s (see Radiotron Designer’s Handbook volume 3, IIRC page 67). Now days we also know more about how the masking principle of the human ear works. This applies directly to how distortion is audible, since the ear converts all forms of distortion into some sort of tonality. In tube amps, a 2nd or 3rd harmonic dominates (depending on if the amp is single-ended or fully differential). The ear treats both the same. Now tube amps make more distortion than transistor amps, but those lower ordered harmonics are crucial as they allow the ear to mask the presence of the higher ordered harmonics. This is why tubes sound smoother on top; its nothing to do with bandwidth- we can’t hear the higher orders! The funny thing is, its been shown that injection of a 2nd or 3rd order also allows the ear to perceive more detail and greater depth- thus accounting for why tube amps tend to be smoother, more detailed and with greater soundstage. The peculiarity is that this actually makes tubes more accurate! I’m very convinced that we need to do more research to find out why this is so, but if you are pragmatic, you don’t need to know why, just do engineering based on the implications:


Now its accepted that we can’t build amps that make no distortion whatsoever and that is what is needed to get around this issue. So instead, it appears that if a circuit is devised that injects a 2nd or 3rd harmonic **of appropriate level** that we can build a more neutral sounding amp. Of course, this sort of thing is readily audible even in a DBX test; but IME people doing such tests will avoid allowing good examples of such to taint their ’findings’. You can’t do it if the test is rigged! You have to start wtih two amps that are based on different design goals rather than two that are built the same way. What I mean by this is, you can use engineering to design an amplifier with low impedance and low distortion, or you can use engineering to build an amplifier that sound neutral according to human hearing perceptual rules. One is the Emperor’s New Clothes, as its designed to essentially look good on paper, and the other is real as its meant to work with rather than against the way we perceive sound. Naturally the latter will measure ’poorly’ compared to the former, but the latter is far more likely to sound real.


If you compare two such amps as in my example above, even in a DBX you can perceive the difference. I’ve seen it/heard it.


One more thing as a sort of BTW... none of this implies tubes or solid state. Its all engineering. To me it just makes more sense to design a circuit based on human hearing perceptual rules than making a nice piece of paper! This is the very reason why tubes are still around, decades on after being ’declared obsolete’. The audio industry in general really hasn’t tackled this issue at all, preferring to keep their collective heads in the sand rather than deal with physiological knowledge gained in the last half century. Pathetic, when you think about it. We really shouldn’t be having a tubes/transistor debate this far on.

Teo, I had a couple of Yamaha B2s in my time ( and a Sony vfet integrated ), and I really enjoyed them. They did not last as long for me as I would have liked, as they developed problems after long time ownership. Repair was nearly impossible to get done, for whatever the reasons ( unavailable parts supply if I remember ). I handled them with care since new, and never over taxed them. They just failed. Sold them for parts.... Atmosphere, I do not see much debating about tubes / transistors as much today. Much more debating about Class D, power cables, passive vs. active, and occasionally speakers ( horns, panels, boxes ). There seems to be an acceptance of both, imo, and that the camps of tubes and transistors have come to a stalemate. just from my readings here, and elsewhere. However, as a manufacturer of tube gear, you obviously are seeing the debate continue. My best. Enjoy ! MrD.

@mrdecibel  Its on this thread too:

No, in my limited experience, I often don't hear the difference between amplifiers (with the exception of underpowered or tube-bloated amps)

The comment is ridiculous, but one that is common in this debate, as if, somehow, hearing how tubes do things is an exception to this DBX nonsense.  The thing is, its become so ubiquitous that we don't even see it sometimes. The thing is, tubes get docked for having a higher output impedance and thus causing a frequency response error (which is often true, but also often very slight) while at the same time no-one says anything about the colorations caused by distortion. Brightness and harshness, ubiquitous to solid state, is indeed a coloration. But we just accept that this is so, and somehow its the norm. But if you listen to real music, that brightness and harshness at volume isn't there and a good tube based system doesn't have it either.


What I am saying in all this is if we collectively did our engineering homework, we could have solid state that doesn't sound harsh in any way. But, we don't, so the beat goes on.

MrDecibel...you said exactly this, "You stated you were in a band, so I believe your ears are shot, and unfortunately, you probably did not use ear protection." That's the comment I was referring to...and I also know different amps obviously sound different or I'd have no preferences...that would be boring...I can say that great amps get music to the speakers  in ways that can be tonally similar, but talk to any reasonably experienced electric guitar player and you can get the drift that all guitar amps are different, even among the same versions! I like the recent discussions about Nelson Pass researching (and atmasphere's further explaining) and implementing the adding of even ordered distortions into a circuit, as maybe that narrows the gap between a great tube amp's "musical" tone and that of well measuring SS amps, some of which also do a good job...my tube amps are a revelation of tonal "correctness," even to my recently cleaned old ears.

Mr decibel,

the problem with those two designs, is that they were only partially V-fet, as the transistors were not available to make them fully v-fet.

thus.. the chain of signal manipulation and amplification was inherently non-linear in gain, even though the V-fets in situ, were linear gain.

the whole chain must be linear gain v-fet, otherwise it will be colored enough that it is notably more difficult to discern what good the v-fets were bringing to the table.

Of the two, the Yammie was probably the better unit, as it had some middling sized v-fets in the driver stage, IIRC... and then the output stage was all v-fet.

Only ONE Sony unit had a second and singular ’small signal’ V-fet in it other than the final output transistor stage, and that is the Sony TA-5650 integrated amp. It had a set in the phono section.

wolf, I understand I said it. I was creating a situation, an excuse, for roberjerman, as to why he always claims " he hears no difference between amplifiers ". I could have said he worked in construction as a jackhammer operator, without using ear protection, but I wanted it to be music related. I am sorry, as I know and respect, that you are in the live music industry. BTW, I do know people in the music industry, and other industries, who have bad hearing because of their everyday life occupations. Atmasphere, I obviously missed that. Always, and Enjoy ! MrD.

wolf,
Non linear gain transistor (all fet and BJT): odd order harmonic distortion generated.

Linear gain transistor (Just V-Fets): Even ordered harmonic distortion generated.

~~~~~~~~

A general note:
the human ear: incredibly sensitive to non linear transient distortion. That’s pretty well all it does, is detect that. This is how the ear works, fundamentally. Down to the less than a few hundred thousandths of a second on a pair of transients.

Never mind the sensitivity to harmonic mixing and levels, and added in is that this is all done by the world’s most sophisticated FFT analyzing hardware: the human brain.

since this is directly tied to learning, discernment, intelligence neural connectivity and so on, it varies among people as much as the human IQ range.

So we can get to audio intelligence on a rarefied level and then back to the other end of the scale, where rudimentary hearing could be the description.

so we can’t let Mr rudimentary hearing yell at us that ’it is all the same’.

It is all the same..sure... if your hearing takes the shape of the IQ of a gut shot open sore covered pear on skid row.

These are indisputable established facts about human minds and human hearing.

One should not try to debate it, unless one wants to show everyone how little one understands and little one knows. To do so, is to come onto an audio forum and say something akin to : ’I just peed my pants’.

If a person can accept even just a whiff of that, then they’ve bought the whole thing as it’s like pregnancy, there is no ’just a little bit’ pregnant. If it is real at all..even in the slightest... then so is the rest.

Thus, stay out of the cable debates and out of the fuse debates and whatnot, as one’s place is not there. Leave it to the people who hear it as they are like high end physicists in debate - when it comes to hearing. It’s their area, let it go. If you don’t have the chops, STAY OUT OF IT.

This is why cable debates and whatnot are being banned at forums. For all the right reasons. All of those reasons are human, logical, scientific, and utterly real.

Daveyf- the DartZeel is still my favorite SS amp after all these years and I've compared it at a local dealer with the newer Dagostino stuff. I think it was released in the early 00s with a few upgrades since.

I owned the Concentra 2 integrated which I found a bit overrated at the time and later heard the 1 was actually better. When JRDG went digital, I picked up a pair of used 201s and sold them two weeks later.

I would agree with others that the move to lower or no global negative feedback in circuit design has been a positive. But Dart, BAT, and several others have been doing this for 20 years now.

Well, I may have "peed my pants" but I know an empty argument to authority when I see one..

“I know what I know and hear what I hear.” 

>>>>Boy, how often do we hear that? 😬

Geoff, as often as I say it, but seriously. Twice, in my past, I admit, I could not hear any differences, using your Teleportation tweak. Personally, I knew a fella who claimed it is very real, and I never doubted him, as many people seem to do, when they do not hear something themselves. Enjoy ! MrD.

Well, I may have "peed my pants" but I know an empty argument to authority when I see one..

It’s not an appeal to authority, It’s a notice about dunning-kreuger and how it creeps into the knowledge base re human hearing and audio electronics.

How that ignorance chooses to express itself as authority, because it is built out of an internalized and then projected -- unrealized ignorance. (a mildly oxymoronic word pairing, but ultimately--applicable)*

The kind of ignorance that cannot be surmounted because the capacity to do so is not in evidence.

I wish it were otherwise.

The vast number of times the folks who do hear the differences simply keep their mouths shut and tolerate the intrusion of the ignorance. After all, it is the thing that decent folk do.

Most of the time I do the same. But every now and then, I state the case and the facts clearly and openly.

~~~~~~~~~~~~~~~~~~~~~~
*I’d be happier if some folks would realize they simply don’t have the hearing chops and thus -- let it go. Instead they fall back on book learning and numbers... and attack via dogma. If they had the hearing chops, then they could investigate the why of the differences, but no....so it’s blunt objects on the terror march for everyone -as the standard playbook...

 @keithr   I would agree that the Dartzeel amps are certainly at, or near, the top of ss amps..as to SQ. What is interesting to me, is that the Dartzeel amps I have heard are not significantly superior sounding to my Rowland. Whilst they better the older design in some areas, mostly in their ability to resolve inner detail and slightly in their top end reach...I don’t think the differences are night and day. 
Unfortunately like you, I feel the new generation of Rowland Class D amps are a step backwards...in SQ. Same goes for the other class D amps, like the Mola Mola etc.,

Having read most of this thread, I reflect on my 12+ year old McIntosh MC501 mono block amplifiers.  Paired with a tube pre amp, driving 3.6 Maggie’s.

McIntosh has a certain “sound” and paired with planar speakers they still speak to me.  

Could my my system be better, most likely, but at what cost?  Being married to a world class Economist, marginal cost versus marginal gain is our mantra.

I understand current technology has moved the price much higher, the question is, IF you can hear it, is the price worth it?  

This is is an empirical issue that is answered differently by each individual.

There is much to be said for component synergy and when realized, it takes a LOT to move one off that sweet spot.

Teo, it's an appeal to authority because it isn't backed up with any evidence or answer, merely assertion about talent/credentials.  Your response reduces to an irrelevant and incomplete assertion of what ears do (even if we stipulated that, it wouldn't necessarily bear on audibility of differences), and then has several paragraphs that can be summed up as "I'm awesome, you're an idiot, get off my lawn".

• I remain open to the possibility that I am an audio philistine, but I have my doubts given my long and continued experience with live music, the reference standard
  
• I have admitted I sometimes hear differences between amps, but, after reviewing evidence (incomplete?)  I am also open to the possibility those were explainable by power/obvious artifacts or simply not objectively audible
• I have explicitly asked for further evidence that I may have missed and shown people what I have reviewed.
• I've freely admitted I enjoy the hobby no matter which way my beliefs go on these subjects, and, after all, I don't listen blind. 
  
• But who wouldn't want to know?
  

Your response to this is "you're an ignoramus, get out of the hobby".  This attitude closes, rather than opens, minds.  Furthermore, it is suspicious.  I've come to understand from my 31 years of business experience that nasty bluster is most often a smokescreen.

“I’ve come to understand from my 31 years of business experience that nasty bluster is most often a smokescreen.”

>>>>>Appeal to Authority alert 🚨

@geoffkait - I view it as more of a probabilistic inference, but I'll happily grant your point if it helps turn the dialogue in a more productive direction.

I have admitted I sometimes hear differences between amps, but, after reviewing evidence (incomplete?) I am also open to the possibility those were explainable by power/obvious artifacts or simply not objectively audible

What is 'objectively audible'??

Hearing amplifier differences to an educated ear is no different, than, to an experienced race car driver feeling a bit of difference on the accelerator pedal with a new small tweak done to the engine, which I have witnessed, living near Daytona. Or, my best friend, a guitarist, picking up 20 similar guitars by the same manufacturer, and stating one is preferable to him, by sound and feel. Or maybe, a certified wine sommelier who does tasting for a manufacturer before they decide to bottle it. I understand the doubt people have, but, does it really matter to continue the argument ? The reality is, if we all, the audiophile community, heard no differences, wouldn’t the high priced gear go bye bye, or, just 1 or 2 manufacturers would be left for all of us ? I say, let those folks, such as ahofer, be, and let us all just enjoy the realities of our hobby. It is getting tired, all of the naysayers and " trolls " ( yes, I needed to use the term ), telling us, it is in our minds, or, we are lunatics, or whatever. I have been trying to ignore these folks, but as always, sucked right back in to the arguments and discussions. Just some thoughts. Enjoy ! MrD.

Feel free to augment or quibble, but I would call an "objectively audible difference" between amplifiers as follows:  when the equipment is gain-matched to be sure the difference is not simply due to different overall volume levels, listeners can still repeatably distinguish between different pieces of equipment *only by listening*.

After reviewing what I can find online, it seems people, audiophiles and engineers very much included, have a lot of trouble with that, especially with respect to cable, differing digital resolutions,and reasonably powered amps that meet or exceed (essentially mid-fi Japanese) distortion specs. 

I see a lot of people here asserting confidently that they can easily do this, but not a lot of verifiable evidence.  That really  piques my curiousity. Although we are talking about amps here, I'm even more curious about high-res digital.  

Even if I came away fully convinced of an extreme objectivist case, I would still probably go for lower distortion, high quality amps, I would probably still by high-res digital (after all, it should  speak to the company's dedication to high audio standards) and I would still audition equipment mostly to ascertain whether the experience was likely to give me pleasure every night, as opposed to just on paper.   But I'm very curious, and I think hobbyists (but perhaps not dealers who rely on the constant tweak & upgrade cycle) would benefit from an open mind..

btw, I totally reject the idea that only self-appointed "Golden Ears" should engage in this discussion.  That seems not only snobby and unintentionally hilarious, but far too exclusive for what is, sadly,  a hobby seriously on the wane.  Don't you agree? To say otherwise seems like a formula for devolving into incestuous irrelevance.

The reality is, if we all, the audiophile community, heard no differences, wouldn’t the high priced gear go bye bye, or, just 1 or 2 manufacturers would be left for all of us ?

I'm not sure. First of all, we'd have to concede we don't hear differences, second, we'd have to decide that the other expensive hallmarks of quality don't matter enough to pay for. Finally, there are still features, appearance, and ergonomics to consider.  In sum, no, I don't think it would change as you suggest.  Consider the high-end watch business.

You bring up the sommelier analogy. I've always considered it a point in that industry's favor that it's highest accreditation requires an incredibly difficult blind (to label) identification process.  But even in that test, there are many other hallmarks other than taste (color, viscosity) that inform the well-defined method that passes the world's hardest test.  There is a great book about that called "Cork Dork" by Bianca Bosker, I highly recommend it -  if you can accept a referral from a "troll" such as myself.  Yes, I like wine as well, and I'm certain that enormous amounts of contextual subjectivity enter into my evaluation of each sip, and I'd love to understand it better.  That, rather than stuffy assertions of exclusivity, is what the hobby is about.

@atmasphere   You bring up a great point! What is "objectively audible"??
I suspect that "objectively audible" is going to be far more objective to some than others. Possibly those that have made up their minds in advance that no such audible differences exist, will get their expectations met..and will NEVER hear any differences.