Thought My Harbeth M40.1's Were Forever Speakers - Guess Not


I've owned my Harbeth 40.1's for about 4 years and absolutely LOVE them.  
The only speakers I've considered replacing them with are the 40.2's, and while I've dreamed of getting a pair, I really never felt like I needed anything more than the 40.1's.  They are SO good!
Well, after a great year for my business along with a great opportunity to buy a pair of 40.2 Anniversary model speakers, I've decided to pull the trigger.  
I'm posting this mostly because I can hardly contain my excitement and wanted to share it with you, but I'm also looking for feedback from others who've made this same move.  
Everything I've read about the 40.2 model has been overwhelmingly good.  I do not expect to be disappointed.  
Thanks!


128x128snackeyp
As a fellow 40.1 owner, I selfishly hope the 40.2's are underwhelming in comparison... however, based upon feedback from shows and reviews, I think you'll be very happy.  I'm interested to hear your comparison of the two speakers. 
@pdreher I hear ya, man.  I have been so happy with the 40.1's I was happy never hearing the upgraded versions.  Just didn't want to know first hand lest I be tempted.  The upgrade bug is strong in me now, however.  
I'll definitely share my impressions.  
Cheers
Congratulations!  Great speakers.  I have a friend that has the 40.2's that I have heard numerous times and they always satisfied.
Nice I'm really enjoying my 40.2's - took awhile to get the placement right in the room but once you get them dialed in they're fantastic.

They seem to play well to all genres of music better than I expected and I really like the way they portray the size and weight of a kick drum or bass guitar amplified or acoustic.  Vocals of course are exemplary on this speaker as well.

What amp are you using?  I was a bit concerned that my LFD NCSE wouldn't be able to drive them properly but it drives them great.  

Harbeth seem to suggest that break in is a myth but I did find that mine opened up a lot after a couple hundred hours and the bottom end in particular changed a lot over the first few weeks.
@audiojedi 

I concur with you. All the Harbeth's I've heard need a few hundred hours to sound their best. I've liked them with Luxman and Line Magnetic. The LM 50-watt integrated works quite well with them and the two box LM that is just 30 very strong watts also works very well.
@audiojedi 
My amp is a Lyngdorf TDAI-3400 and it drives my 40.1's with ease.  
Previously I had a Primaluna Dialogue Premium HP and it also sounded great with them.
@snackeyp 
Any regrets going from tubes to a class D amp?  Every time I'm attempted to go back to SS, I regretted it and have stuck with tube amps for the last several years.  I hear good things about Lyngdorf, just don't feel the need or urge to change amps any more.
@pdreher 
No regrets but sometimes I wish I had the PL tube amp in addition to the Lyngdorf just so I could spend time with both of them since they are both so great.  
The Lyngdorf is the best SS amp I have heard, but it's not a tube amp.  
Hello snackeyp,  

Congratulations on your new pair of Harbeth M40.2 speakers.   I own a pair also and I really enjoy mine. They do take about 200 hours for break in. 
@snackeyp 
Have the 40.2's arrived?  If yes, can you share your comparison to the 40.1's?

Fellow 40.2 owner here....surprised you guys having success with moderate power amplification as I did not find the 40.2 could play full range sound on broad spectrum of rock music until I went from integrated pass labs 250 and vac integrated to pass labs monoblocks....now it can play non audiophile modern rock loud and well...I guess every room has different acoustics explaining differences...

Harbeth are one of my favorite speakers (I owned the SuperHL5plus for a while). I’ve heard the 40.2s a couple times and recently got a nice audition of them at a store (in a big room).


Before I put on my tracks they played a track with a female singer accompanied by a muted trumpet (and I think maybe some light drums?).  I was taken aback! It was probably THE most 3 dimensional, corporeal imaging I’ve ever heard! The singer seemed way back in the "stage" but fleshed out, properly sized and, well, corporeal and dense. When the trumpet entered off to the side, same thing. This big round, tonally convincing trumpet just appeared. The Harbeths have a way of making many other speaker imaging sound flattened and lightweight.


When I threw on a bunch of my tracks there was more excellent soundstaging/imaging - a really big sound. Though I was finding the bass a little pudgy. (Maybe the big room worked for the big soundstaging, but somehow against the bass control?).


Generally it all had the nice Harbeth richness, roundness and weight, with nice accurate-sounding tonality. Though for whatever reason I wasn’t finding myself totally seduced by what I was hearing. There was a bit of a polite, reserved quality to the sound, where it sort of "sat back behind the speakers" in terms of staging and not being tonally forward.The Thiel 3.7s I owned (and to some degree my 2.7s) gave me a lot of what I heard with the Harbeths in terms of image size/weight (though not as much), but with a bit more energy and toe-tapping quality.


My current Joseph speakers also do a great job with bass-driven music, with a reach-out-and-grab-you bass quality.


Still, the 40.2s are one of those speakers that I want to spend more time with some day. Ultimately they don’t really fit my room aesthetically and practically. But they sure have some special qualities that separate them from the pack (in terms of what interests me sonically).


Hi guys,

Sorry for the delay.  It took me a while to get the speakers and set them up.  Holiday madness delayed things a bit.

Here are some initial observations of mine:

Hooked up the new speakers yesterday.

Unpacking these speakers is a chore, and best done by two people, but I didn’t have anyone around to help when I opened mine, and honestly I prefer to do it myself so I can give 100% focus to it and block out the noise.  Moving them is also a chore.  I did have a friend help me with this and I’m glad I did.  It's nice to have the grunt work done and be able to relax and spend time with them now.

I have Tontraeger stands for them, which are perfect IMO.  

At first listen they sounded tight and bright.  Really harsh is the only way to say it.  Not good.

30 minutes later they began loosening up and sounded much better.

Five hours of listening on them now and they are starting to produce their magic.  

Absolutely love them!

They already sound better than the 40.1’s, and that is really something considering how good those speakers sound.

I think they need several more hours of break-in.  Some people have said as much as 200 hours.  Not sure but I guess I’ll find out.

Just took the grilles off, and can honestly say I think they sound better with them on, but the olive wood finish is just too beautiful to cover up!

Feeding them a steady diet of analog and digital music, ranging from folk to classic rock to classical and loving it all.  The best way to describe the sound is that the music just sounds "right."  The sound is so natural and easy on the ears that it calms me to just sit here and play them all day, which is what I plan to do today (it's Saturday and there is freezing rain outside - no need or desire to leave the house).  

I played the new Mofi UH1S copies of Blood On The Tracks as well as SRV's first album last night.  Holy Schitt was that a treat!  This morning it's digital versions of Wilco's library that are providing the magic.  

Thanks,

Peter


Congrats....

How do you feel about the tontrager as it looks a little precarious as a a stand....i am using skylan here in earthquake country LA.
@karmapolice 
The Tontraeger stands are amazing.  Expensive but they look and sound great.  You can add Blue Tack under the speakers but I never have and they stay put for me.  I do not live in earthquake country.  I used to live in Japan and had Sound Anchor stands with B&W 805 speakers.  I never had the speakers fall off the stands but sometimes noticed they were a bit off kilter, probably caused by minor seismic activity.  I added Blue Tack and that solved it.  
@joeinid 
Yes, as far as I can conclusively say right now.
It's too difficult to say I'll be happy with them forever.  Someday I might hear something I like better and switch them out.  Maybe the next gen of 40's will outdo these.  But it's safe to say I will be hanging onto these for a good while.  
I'm very interested in the Tannoy line of speakers, particularly the Westminster and Canterbury models.  I once had the pleasure of hearing Westminsters while I lived in Japan and to this day I've never heard anything so transparent and real.  
I can see buying a pair of them someday if I ever have the perfect room for them.  I can see putting them in a common living area where they don't look out of place.  They are so large they really do require the right size room.  And they are works of art in themselves.  The cabinets are beautifully made.  Very intriguing to me.  
Hi Peter,

Thank you very much. I appreciate your thoughts. I sold a pair of 40.1 with the intention of getting 40.2 but after a few pairs of speakers, I now have Avantgarde Duo XD. Way different sound but I do love them.

Have a very happy and healthy new year.

Joe
Those Avantgarde speakers look pretty cool.  I could never rock those in my listening space but they are beautiful.  
Thank you.

They are fun for sure. I’m considering a pair of 30.2 Anniversary for fun. The 40.2 are probably too big for my space.
Post removed 
@snackeyp 
I'm seriously considering following in your footsteps and upgrading my trusty 40.1's to 40.2 Anniversaries.  I'm assuming you still have your 40.2's and still consider them a sizable improvement over the 40.1's?  Just want to make sure I'm not simply changing flavors for the sake of change.
Paul

@pdreher Yes I still have them and am completely satisfied with them.  No plans to change them out anytime soon, if ever.  I think you will be happy with the upgrade if you decide to go for it.  The improvement over the 40.1's is not small.  
@mapman The 40.2's have all new drivers and tweeters, and the crossover has been redone.  
@snackeyp I never thought I'd part with my 40.1's... but I have a pair of 40.2 Anni's on order.  I'm nervous and excited at the same time, as it's hard to believe another Harbeth model can improve up the 40.1.  
@pdreher  I promise you won't regret it.  I felt the same way as you do now but once I got them I realized what a big upgrade it is.  Let me know your thoughts once you've spent some time with them.  You should know that the first hour or so of listening is pretty awful.  Once they loosen up though, they are magical from the first day and only improve with time.  
@mapman ,

"What exactly is the difference between 40.1 and 40.2?"


Careful my friend, you're transgressing one of the cardinal sins of audio etiquette.

Questions such as that one are almost taboo amongst audiophiles. The latest versions are always supposed to be WAY better!

Here's what Alan Shaw himself had to say on the matter in an interview  originally published in a 2017 Paul Seydor review for TAS.


--------


Interview with Alan Shaw on the Genesis of the Monitor 40.2.


(Q) Please compare the Monitor 40.2 to earlier iterations.

The main improvement in the Monitor 40.2 is its completely redesigned crossover network. The obvious functions of the crossover are the division of the audio spectrum among the drive units and the level adjustment of the contribution of those drive units. The less obvious function is that the crossover overrides the ear’s sensitivity to sound coming from more than one source. 

In nature, the sounds we hear emanate from point sources that give them directionality. For me, seventy-five percent or so of the total design for any new Harbeth model is precisely this issue of making a convincing junction between the sonic contributions of the drive units in order to simulate a point source. 

Also, the work in developing the SuperHL5plus opened up techniques that I could weave into the Monitor 40.2. 

It’s often about small, incremental steps that can cross-fertilize from one model to another if they’re appropriate.


(Q) One difference I immediately heard between the new model and the original is the slightly deeper bass extension of the 40.2 but slightly less overall bass around, say, 100Hz, the so-called warmth region.

The Monitor 40 was originally conceived as a drop-in replacement for the Rogers LS 5/8, a speaker in wide use in the late nineties in the BBC and elsewhere in British broadcasting. It was quite a shock to procure a pair from a disbanded studio and measure and listen to them under domestic conditions, which they were never designed to be used in. The entire frequency response had been tuned to the highly absorptive acoustic environment of “old school” studios of the era. Nobody could foresee how the architectural minimalist trends would become so popular among consumers, and even among studio designers. 

Since the Monitor 40 project now covers over fifteen years, the bass has been progressively optimized, that is, made drier, for those less damped acoustics. So the 40.2 is better balanced for the majority of modern rooms.


(Q) I’ve always found your speakers to be notably coherent, yet so far as I am able to tell, you don’t employ special methods to achieve this, such as physically staggering the drivers so their voice coils line up, etc. Can you comment on this?


Coherency is primarily a crossover issue. Conceptually the difficulty lies in the way the ear/brain interprets the junction between the two or more sound sources. It doesn’t take much of a mismatch in level or phase for the subconscious to needle the brain with awareness that there is something wrong. I was lucky to be sensitive to this matter as a rookie designer some thirty years ago. By trial and error I developed an approach to getting the best out of the drive units, an approach I’ve basically replicated in all subsequent Harbeth designs. I’m sure other loudspeaker designers have their own lexicon of tricks.


(Q) Both the coloration and integrality of Harbeth speakers is really low, yet your drivers are not made from the same materials.

Coloration takes many forms. I recall asking my predecessor, Dudley Harwood, from whom I purchased Harbeth, as he handed the keys of the company to me, for a definition of coloration. Taciturn at best, he replied, and I quote, “You will know it when you hear it.” 

When I started designing, coloration seemed so extremely obvious, to my ears anyway, that even though I didn’t technically understand where it came from, I kept designing until I had eliminated it. Loudspeaker drive units are energized by the music, which causes their diaphragms to be shocked into motion. These shockwaves substantially radiate through the diaphragm and generate sound waves in the room. Unfortunately, a proportion, a very small proportion, bounces around inside the diaphragm itself and interferes with successive musical events. You can imagine that within the first thousandths of a second after the music starts that a background of residual energy will have built up in the diaphragm and will be topped up by successive notes. It’s this sonic mush that at best fogs the overall sound and at worst introduces audible coloration, where some notes are dominant. 

The pioneering research that we, in collaboration with government funding, conducted in the 1990s proved beyond doubt that all commercially available materials, including all the popular ones, used in loudspeaker manufacturing are really unsuitable for the task. Their molecular structures, particularly the inter-chain bonds, have characteristics that nip energy from the music they’re attempting to reproduce, particularly in the presence and lower treble region. 

The low coloration that you hear in the Harbeth loudspeakers, especially in that critical musical band, is a direct result of us conceiving, proving, and blending different materials for their acoustic properties.



(Q) Do you still employ recordings of your daughter’s voice to do a final voicing of the speaker?

My daughter is now in her early thirties and has quite a different voice to the nine-year-old that I recorded all those years ago. Good news, though—my granddaughter is nearly four years old and I am grooming her for a life in loudspeakers! 

Seriously, the ear/brain is highly optimized for detecting subtle nuances in human speech. If we guess that our ears have been under development for some millions of years, we know that the first musical instrument appeared around fifty thousand years ago. This is far too recent to have had any physiological impact on the development of the human ear. 

It follows then that to use our ear as an analytical instrument when grading loudspeakers, it’s the reproduction of voice that can tell us a lot about the mechanics of the loudspeaker. 

Note that the human vocal tract is a soft tissue structure with plenty of “damping” thanks to being nourished by warm blood and elastic tissue. All of the undesirable characteristics of loudspeakers that are commonly mentioned such as spitty, ringing, wiry, harsh, biting, gritty, bright, brittle, and so on are likely to be the consequence of hard materials in undamped resonance. No wonder then that convincing natural sound is so elusive in home hi-fi.



(Q) I have always been curious about this whole matter of voicing. How do you “voice” a speaker system without the use of, say, an equalizer, whether analog or digital?

“Voicing”—I don’t like this word and don’t use it. All it means in a fancy way is of setting the contribution of the drive units so that they are blended adequately to fool the listener’s ear into thinking that he is actually in front of the performers, live. 

Present one hundred loudspeaker designers with a cabinet fitted with drive units and a box of crossover components and you will end up with one hundred different voicings. 

Which one is correct? 

That’s a tough question because those one hundred designers will have two hundred different ears. They also evaluate sound differently, different instruments will appeal to them or not, they’ll be sensitive to different colorations and some may see themselves as wizards with the power and right to “interpret” the recordings. 

Some may use test and measurement equipment that will guide them towards a relatively neutral contribution of the loudspeaker, others may voice entirely by ear. 

Whatever the strategy, expect a wide variation in sonic performance. 

If, however, a degree of objectivity is introduced, those speakers could be graded. 

One attack would be to record a human voice under non-reverberant conditions and to switch between that human sitting next to the loudspeaker and his or her voice reproduced over the loudspeaker. 

My experience is that ninety percent of the candidate loudspeakers would be dismissed as having characteristics not at all present in the live voice. 

It’s a great pity that the word “voicing” is rarely associated with the concept of listening to a human voice over the loudspeaker!



(Q) Also, how do you control the dispersion of the response?

In reality there is not much that can be done to control the dispersion of loudspeaker drive units unless they are fitted with horns or similar diffusers. 

The BBC’s view was that it’s the on-axis response that’s paramount. This has merit, providing the listening environment can absorb the off-axis sound that is splashed onto the sidewalls. In the domestic environment often the sidewalls are untreated, even though there may be snug carpet on the floor. 

We’re back to the issue of careful selection of crossover frequency and contouring the fade-out and fade-in of drive units so that off axis, where they are becoming beamy due to their diameter relative to the frequencies they are reproducing, the transition is smooth.



(Q) You still use a relatively thin-walled enclosure with lots of bracing for support and stability, but no heroic measures, so far as I can tell, to dampen resonances as such with the use of synthetic materials or super-rigid construction.

Cabinets: We do indeed live in a world where visual impressions seem to count for so much. The physics of panels—those forming a loudspeaker cabinet—say very clearly that thickness and stiffness do not guarantee low sonic contribution. Indeed, rigid panels can move the latent resonances away from the bass region and up into the midrange where they are energized by the music and can sound extremely objectionable. 

After extensive research the BBC concluded that a relatively thin-walled but sturdily braced cabinet could be steered by the application of damping into a state of relative inertness, in a way that no thick panels could be. This gives the thin-walled cabinet designer a whole armory of tricks for better sound.



(Q) One of the arguments you make in Harbeth literature is that exotic parts and wire are not necessary for state-of-the-art performance, merely parts and wire of requisite specification that will be reliable under dynamic conditions and for a very long time. I’m sure you know that many, perhaps most, Harbeth users ignore this when it comes to selection of speaker cable (and interconnects).

During my teenage years, music was my escape, and my interest in radio and broadcasting led to an involvement with the local BBC radio station. It was then that I was introduced to the BBC monitor. What impressed me was the pragmatism of the BBC designs, a total focus on simplicity, cost-effectiveness, and real, solid, honest engineering. 

I’m well aware that consumers can select whatever they like, but I worry when the hardware becomes more important than the music and seems to trap consumers in a cycle of dissatisfaction. 

Having said that, I’m acutely aware that it’s the ongoing sale of accessories to consumers, who rarely change their core system components, that helps keeps the audio dealer in business. I’d just make a plea for common sense. If the consumer has the interest and the cash to invest in exotic audio accessories, do so. 

But do so without feeling compelled to apply what may be pseudo-science.



(Q) The 40.2 is among the first Harbeths to use drivers made from Radial2, a new formulation of your proprietary RADIAL material. What’s been changed?

A small few-percent adjustment of the ratio of the key elements in the diaphragm polymeric compound.



(Q) What do you say to those audiophiles who ask, “Well, if you had no constraints as regards price or size, what would an all-out, no-holds-barred Alan Shaw speaker look and sound like?”

Looking back I can see how fortuitous it was that the BBC control rooms are approximately the same size as a typical British living room. Had the BBC control room been three or four times the size of the home listening room, the magic simply wouldn’t have been translatable. 

But your question is about my so-called “Magnum Opus.” Assuming I had the time to develop a speaker for myself, with no need to be concerned about commercialization, what would it look like? 

Actually, now that I have dictated that sentence I can’t actually answer my own question. 

What I do know is that the speaker would unquestionably sound like a Harbeth of today, but I can’t decide what to sketch on that blank sheet of paper when it comes to its physical configuration. 

Perhaps things will become much clearer after a couple of pints—they usually do!


--------

So the gist of it seems to be 'small, incremental steps' and a 'drier bass' over 15 years of development.

The whole article can be found here.

https://www.theabsolutesound.com/articles/harbeth-monitor-402-loudspeaker/

"Drier bass" sounds kinda bad until you ask yourself whether you want wet bass.  Your precis is a classic example of selective quotation.  AS wanted to make the 40.2's more room-friendly, i.e., make them perform well in a larger range of environments, w.r.t. positioning, size of room, and acoustic environment, something that he achieved handily.
@twoleftears ,

"Your precis is a classic example of selective quotation."


"Selective quotation"?

Don't you think that's a little unfair seeing as how I've presented the whole interview in full?

Perhaps a more pertinent question might be as why do you feel that "Drier bass" sounds kinda bad?

Besides, I was hoping to address the question posted by @mapman earlier.

Who better to answer that than the designer himself?
@cd318  Yes.  When your "gist" of these two sentences:

"the bass has been progressively optimized, that is, made drier, for those less damped acoustics. So the 40.2 is better balanced for the majority of modern rooms."

is "drier bass", then yes, that's a classic example of selective quotation.
Just today, I packed up my beloved 40.1's and replaced them with 40.2 Anni's.  I concur the 40.2's have "drier" less prodigious bass and less warmth (more neutral) to my ears vs. the 40.1's.  Initially I missed the warmth of the 40.1's, but was able to bring all of the warmth back by swapping out Gold Lion KT88's with some RAM EL34's... now the warmth is back and the transparency and detailed imaging is even more impressive with the 40.2 Anni's vs. their predecessor.  Small incremental steps of improvement, but noticeable improvement nonetheless!
@pdreher Are these brand new?  I ask this because you need to break them in for a good 20-30 hours before they start doing their real magic.  Others have said 50+ hours but in my experience it wasn't that long.  
I never felt these speakers sound dry, but I guess it could be a factor of the amplification used.  Let us know how they do as they break in and open up for you.  Cheers
The woofer breaks in around 50 and the tweeter around 100.  The midrange undergoes very little change.
Alan Shaw has often said he doesn’t believe in any audible break-in other than after a few initial seconds for the tweeter.

Let’s not forget that he is in a far better position than most of us to compare new and used speakers/drivers - or also that he has nothing to gain by saying this.

Yet some manufacturers and dealers seem to claim (usually without offering any data) that they do believe in it.

If so, and let’s face it the promise of ’break-in’ would be a great tactic to try to shift unimpressive loudspeakers by promising nebulous future improvements, I would hope they are prepared to extend the return date (plus accept at least 50% of the return costs) accordingly.

Confirmation bias on the other hand is definitely real and far more likely to affect perceptions. Especially when large sums of money are involved.

In my experience if a product is not initially satisfactory it is unlikely to become so in future.

In fact there’s just as much chance that the niggles will remain and gnaw with increasing intensity with the duration of time.
The Anni's are demo's... new as of February 2020.  Not sure how many hours are on them, but I'm guessing < 500.
@cd318 Unless you own or have owned 40.2's from new, and have gone through the process, you hardly seem like the best qualified to opine on this topic.  Most of us are posting based on first-hand empirical experience.

ditto @twoleftears 
I've recently been corresponding with a fellow Goner that recently purchased a new pair of 40.3XD's that confirmed he was initially very worried as they were initially very harsh, but finally blossomed after a break-in period.
cd318,  interesting as usual. I've been reading some old papers on the evolution of BBC monitors from the 50's through the 80's. The designers and engineers had to argue with the top dogs trying to build state of the art and best sounding speakers they could. The accountants saying it didn't matter since 90% of the public used garbage speakers anyway and they argued their's needed to be better than the 10% who didn't. Interesting that Shaw used his daughter's voice as some monitors were not designed for music but voice and effect work. Some for use in those old small broadcast vans. 
@djones51,

When I first read about the BBC research it was like a breath of fresh air. Especially after years of reading about ’musicality’, P.R.A.T. and the flat earth approach.

The theory goes that untold millennia of evolution our hearing has been optimised for speech far more so than music which must have obviously arrived much later.

Furthermore, unprocessed speech has a sonic immediacy that many designers (esp those BBC influenced ones such as Harbeth, Spendor and PMC etc) use speech as the key reference point in all of their designs.

They argue that if a design works well on speech it’s likely to do well elsewhere, which naturally enough implies that if a design doesn’t reproduce speech very well - then what’s the point!

This idea seems to have stood the test of time as even after half a century later it’s very difficult to argue against this reasoning.

Alas, those were the days when the BBC had a far larger research facility and seemed far more concerned about consistency and conformity over its worldwide broadcasting endeavours.

Nevertheless it is to their credit that they are willing to openly share the results of their research in such a matter of fact way.

https://www.bbc.co.uk/rd/search?query=Loudspeaker&submit=


@twoleftears,

My experiences of break-in is based upon various speakers that I have owned and I can see no reason why Harbeth M40s would be much different from any other speaker.

Since this a public forum you are at complete liberty to disregard my opinion at leisure (and casually talk about 100 hours for tweeter break-in??).

However I would have hoped you would give more consideration to the opinions of the loudspeaker’s designer.

Someone who has worked on the design of the M40 for over 20 years.

No problem, it’s your choice, as unlike yourself I have no vested financial interest in any of this.

In any case I would hope I have explained well enough for you to understand why I might prefer Alan Shaw’s opinion over yours.
By that logic all Harbeth owners should limit themselves to Hegel amps.  Which is clearly not the case.  Some of us prefer to trust what we hear ourselves.
@twoleftears ,

'By that logic all Harbeth owners should limit themselves to Hegel amps.'


When did Harbeth ever say such a thing?

As far as I'm aware no one from Harbeth has ever recommended any particular manufacturing brand of amplifier.
"My position on Hegel is abundantly clear. It is the only hifi amp I have ever measured in my lab that has what I consider to be a proper gain structure throughout." ~Alan Shaw

The Hegel H590 is at the top of my list of amps I want to hear with my 40.2A's.  There is a local dealer near me that I am planning to ask for a demo.  
My current amp is a LFD NCSE Mk3 and I am really happy with it, but when Mr. Shaw speaks I tend to listen.  
On HUG, the Harbeth Users Group forum, the "A-list" of amps thread makes interesting reading for the diversity of makes and models that owners are using.  For a manufacturer testing or even displaying speakers, an amp that is reliable and whose sound is neutral and repeatable may certainly be the way to go, while an individual in a home environment may have other priorities.
@snackeyp ,

"..but when Mr. Shaw speaks I tend to listen."


Me too. I cannot think of any single individual in the world of audio from whom I have learned more.

Peter Aczel and Siegfried Linkwitz are the only names that get anywhere close, but that was later. 

I found the Harbeth User Group (HUG) a difficult learning ground as many of the concepts and ideas discussed there were in contradiction to what I already knew.

I'm more than happy to admit that I am not the quickest learner. Certainly not when it means having to overturn my existing knowledge.

Learning new things is evidently far easier than having to correct faulty existing knowledge. You only have to look at lifelong voting patterns to see how difficult it can be to give up on long held opinions.

As Alan Shaw says, one of the points behind HUG is to no less than establish a growing body of reasoned audio knowledge that will last the ages. 

His aim is to build and expand on the work done by such BBC luminaries as D.E.L. Shorter, Spencer Hughes, and Dudley Harwood.

Long may he continue.

https://www.harbeth.co.uk/usergroup/