Listening #203

"Let's get real, real gone for a change."—Elvis

I.
As Plato mentioned in The Sophist and thousands of art historians have noted in the years since, Greek sculptors distorted the human figure by enlarging the head and shoulders. They did it on purpose. If they didn't, when viewed from below, it would look wrong. Poets—real ones, I mean—distort smaller truths in order to create larger ones. Every type of musical temperament is a means of distorting the relative sizes of sub-octave intervals—or, in fixed-pitch instruments, creating compromises—in order to create a pleasing result. Human interaction is all about distorting the truth: If you always told everyone what you're really thinking, you'd be beaten to death by the age of 9.

Except for medicine, transportation, civil engineering, and the mixing of drinks, every human endeavor involves some degree of distortion, sometimes unexpected but just as often intentional and well-accepted—and sometimes naturally occurring.

Any music recording, of even the simplest piece, contains an enormous amount and variety of information: What pitches did the performer(s) produce? What were the shapes of those notes, in terms of the proportion of attack, sustain, and decay components in each one? What were the temporal relationships between the notes—the rhythm and the pacing? In what sort of space was the music performed and recorded? How close were the performers to the listeners/microphones? What were the timbral colors of the sounds their voices and instruments produced? What were their textures? How big was the sound they created? How forceful? How loud at its loudest and soft at its softest? What other audible things were going on—passing cars, coughing listeners, creaking seats, sighing babies—when the recording was made? Every piece of playback gear ever made distorts at least one of those things. Probably more.

And you can believe me when I say: Unless you live in a concert hall, unless your ears are truly indefatigable, you do not want a playback system that is 100% free from distortion. To paraphrase my friend, audio critic Steve Guttenberg, why in God's name would you want to hear a perfect reproduction of a concert grand piano in a room in which the real thing would sound terrible? (And do please bear in mind that that can be said of 99% of all the rooms on the planet.)

Like most people, you probably have an internal checklist, whether subconscious or not, of the distortions you wish to be free from and those you tolerate or perhaps embrace. God knows I do. As people who know me have remarked, in these pages and elsewhere, I tend to listen to recorded music at playback levels slightly lower than the average, certainly lower than the stuff would have sounded in real life. That too is a distortion, one that makes music more lifelike in the aggregate to me. Your own checklist is surely different from mine and from those of your friends. It's useful to note that the intricacies of human perception and the frailties of the mechanisms we use to perceive the world render a comprehensive inventory of distortions unreliable.

That said, certain distortions of sound are always bad, always to be avoided if possible. At the top of that list are mechanical limitations that prevent playback gear from working as intended (footnote 1)—a chipped or severely worn stylus that can't stay in the groove, a tonearm whose bearings won't allow it to follow the groove, a loudspeaker whose voice coil is in physical contact with the sides of its gap, and so on—and electrical phenomena that overlay music's complex wave with nonlinear, non-sinusoidal waves. (I fondly remember an event from my early 20s when a technician friend put my Marshall guitar amp on his test bench and we watched it turn every signal that came its way into something that looked like a sawtooth wave. It was pretty cool, but not something we should want from our hi-fis.)

Throughout the history of audio journalism, a number of technically minded, self-righteous, or Puritanical writers—the founder of this magazine included—have delighted in ridiculing those, including me, who accept that the evaluation of playback gear is, at its core, a discourse on the distortions we find most or least acceptable. It is their inflexibility that deserves ridicule: We have been right all along.

Put another way: "How much distortion does this thing have?" is the wrong question, and "What kind of distortion does it have?" is only slightly righter. The most important question we can struggle to answer is, "In what sort of setting and to what sort of listener does this thing offer a soul-satisfying degree of musical realism sufficient to justify its expense?"

II.
If Acoustic Research founder Edgar Villchur was truly an audio-industry visionary, and if his work was as influential as many of my colleagues claim, why is it that products embodying his two most conspicuous contributions to our field—the acoustic suspension loudspeaker and the suspended-subchassis turntable—are now as rare as tooth fairy sightings in West Virginia?

Consider the acoustic suspension loudspeaker, in which a woofer is designed and manufactured with a surround and spider so loose that the drive unit's free-air resonance is impractically low, and its ability to restore cone position in the absence of a signal is essentially nil—unless and until that driver is fastened to the baffle of a smaller-than-average sealed box such that the springiness of the air trapped within supplies the necessary restorative force and raises the free-air resonance to a usefully higher yet lower-than-average frequency, all in the interest of providing deep bass extension from a less-than-large loudspeaker.

In that light, acoustic suspension seems a perfectly apt name: Villchur described his development process by saying he cut away part of the spider from a third-party driver—according to legend, this was a Western Electric 755 full-range unit—and removed entirely the cone's integral surround, replacing it with a fabric surround made from mattress ticking. (He credited his wife with creating the necessary pattern.) Thus modified, the driver would have no suspension of its own, so an air spring would have been required for the thing to work at all.

A few factoids about acoustic suspension:

• Acoustic suspension loudspeakers are inefficient—more so than any other means of loading a dynamic drive-unit, be it reflex loading, aperiodic loading, isobaric loading, Karlson loading, transmission-line loading, quarter-wave pipe loading, or, especially, horn loading. And that's a shame, because, all other things being equal, as efficiency goes down, distortion goes up. Way up.

• Another consequence of the inefficiency of acoustic suspension loudspeakers is their need for a higher-powered amplifier, something Edgar Villchur dismissed by noting that, at the time he created his design—which more or less coincided with the introduction of solid-state amplification—power was cheap enough to not be a concern. Here I must once again ask a question that I posed in this space just a few issues ago: Since when is wastefulness considered a hallmark of good engineering?

• In the 1960s, noted loudspeaker designer Paul Klipsch, whose degree was in electrical engineering, began appearing in public wearing a lapel pin bearing the word Bullshit, sometimes tucked underneath his lapel, sometimes not. Word has it that the claims made for the acoustic suspension principle by Edgar Villchur, whose degrees were in art history and education, were the original target of that informal campaign to rid the world of nonsense. (Also according to legend, the two men buried the hatchet after a while.)

In the most recent edition of our semiannual Recommended Components feature, a total of 84 loudspeakers were listed. Of these, only three are sealed-box designs—which in the decades before Edgar Villchur went into the loudspeaker business were simply called infinite baffle speakers. They are the Magico S5 Mk.II, the Graham/Chartwell LS3/5a, and the Klipsch Heresy. Of the three, only the Magico is described by its manufacturer as an acoustic suspension design. (The Klipsch offers very limited bass extension from a 12" woofer—a combination of qualities opposite to those claimed for acoustic suspension loudspeakers—and according to Derek Hughes, who engineered its drivers and crossover, the Graham/Chartwell LS3/5 and variants "would not be considered acoustic suspension," adding that the BBC referred to the speaker only as "closed box: they kept away from commercial descriptions.")


Footnote 1: An exception would be the very first compact disc players of the early 1980s, which sounded wretched when used as intended. They were perverse in the sense that tobacco—which, when used as intended, is lethal—is perverse. Oh well.
ARTICLE CONTENTS

COMMENTS
Bogolu Haranath's picture

Is that AD saying, "No matter what, I'm not gonna give up on those tube gear and analog play back gear" :-) .........

JRT's picture

MAPD combines aperiodic damping with acoustic suspension, by loading a suitable woofer in small chamber sized Vas/3 connected through a flow resistance to a larger otherwise sealed chamber sized equivalent to Vas.

The short version, archived George Short's defunct website, North Creek Music:
http://web.archive.org/web/20080207011833/http://www.northcreekmusic.com/MAPD1.htm

The longer version, his master's thesis, circa 1988:
https://vtechworks.lib.vt.edu/handle/10919/45955

John Atkinson's picture
JRT wrote:
The short version, archived George Short's defunct website, North Creek Music: http://web.archive.org/web/20080207011833/http://www.northcreekmusic.com/MAPD1.htm

The longer version, his master's thesis, circa 1988: https://vtechworks.lib.vt.edu/handle/10919/45955

Very informative links. Thank you for posting them.

John Atkinson
Technical Editor, Stereophile

JRT's picture

I just posted the links. George Short did all of the work.

18-20 years ago, Siegfried Linkwitz suggested some interesting filter media with more linear flow resistance for use as the airflow resistance in cardioid alignments, also applicable where aperiodic damping resistance would be used.

Interesting read at the link:
https://www.linkwitzlab.com/frontiers.htm#A

Awsmone0's picture

It’s interesting how the original meaning of factoid especially in North America has come to mean something different as Norman Mailer coined it as a falsity repeated so often it became accepted as fact, rather than the other usage as a tidbit of true information ......which were you intending ?

John Atkinson's picture
Awsmone0 wrote:
It’s interesting how the original meaning of factoid especially in North America has come to mean something different as Norman Mailer coined it as a falsity repeated so often it became accepted as fact, rather than the other usage as a tidbit of true information...

This is a particular bugaboo for me. Mailer coined the term in his book on Marilyn Monroe, which I read when it was first published. He meant it as something that wasn't true but which everyone thought it was or even should have been true. The change in meaning has always irritated me, but as the great god of the English language Fowler wrote, usage trumps pedantry!

John Atkinson
Technical Editor, Stereophile

Awsmone0's picture

John totally agree

On the issue of distortion as mentioned in this article, you commented on the Hyperion amplifier as editorialising the signal “ I feel they should be engineered to be as close to neutrally balanced as possible, and not designed to produce a "tailored" sound, as the Hyperion seems to be”
Read more at https://www.stereophile.com/content/ypsilon-electronics-hyperion-monoblock-power-amplifier-measurements#zzU1ueDBJpgGJhmo.99, but Nelson Pass has come out and said he deliberately manipulated the distortion of his .08 from neutrality because of what he learnt from customer feedback, isn’t this more deliberate editorialising than Hyperion just reducing feedback overall ?

Also given your liking for the Lamm M1.2, doesn’t appear that certain amplifier transfer functions are interpreted as more “ musical”

John Atkinson's picture
Awsmone0 wrote:
given your liking for the Lamm M1.2, doesn’t appear that certain amplifier transfer functions are interpreted as more “ musical”

That appears to be the case and as you can see from my review of the Vandersteen M5-HPA amplifier in the current issue, I liked an amplifier that produced more distortion than I liked to see. But in the case of these two amplifiers, the harmonic distortion is 2nd- and/or 3rd-order and doesn't significantly change with either frequency or output power. I suspect that these factors produce an amplifier that tends to step out of the way of the music, as long as it doesn't also produce significant intermodulation distortion.

John Atkinson
Technical Editor, Stereophile

Robin Landseadel's picture

"why in God's name would you want to hear a perfect reproduction of a concert grand piano in a room in which the real thing would sound terrible?"

Because I used to have a Steinway B in my living room and it always sounded better than any recording of a piano I have ever heard?

Ortofan's picture

... piano, try "Malcolm Frager Plays Chopin" on the Telarc label.
http://www.arkivmusic.com/classical/album.jsp?album_id=8750

Awsmone0's picture

We have a grand piano in our room and it’s wonderful and much loved

Recording piano given its power and transients is very very difficult

The gentlemen who builds Stuart pianos told me they had great difficulty finding a microphone that could capture its dynamics and timbre

But yes I am trying to reproduce recorded piano as well as it has been recorded why wouldn’t I?

Robin Landseadel's picture

You've got the right question, I was merely pointing out a wrong question. Have yet to hear a convincing recorded piano.

Awsmone0's picture

Yeah the dynamics are pretty impossible

The upper octaves can be convincing but those below middle C where there is more soundboard not so much

The recording of the Stuart piano is pretty good

Robin Landseadel's picture

"As I once wrote about modern listeners who compare various conductors' recordings of standard-repertoire pieces in the manner of baseball fans comparing the stats of famous players—Furtwängler in particular would have been horrified."

Ya gotta admit, though— Furtwängler threw one hell of a spitball.

Ortofan's picture

... an old wound that had not yet healed?

I. Back to the 'pleasant versus accurate' debate:
https://www.stereophile.com/content/manufacturers-comment-0

II. Can we send AD back in time to experience the 'live versus recorded' demonstrations that AR conducted using their acoustic suspension speakers?

In the meantime he should listen to the Spendor Classic SP200 sealed-box speakers:
https://www.spendoraudio.com/wp-content/uploads/Spendor-Classic-Data-Sheet_Sept19.pdf

Also, he should try the Thorens TD-550 suspended sub-chassis turntable.
It's large enough to accommodate a 12" tonearm such as the SME M2-12R, into which AD could install his favored SPU cartridge.
https://thorens.com/en/thorens%C2%AE-td-550.html
https://sme.co.uk/audio/product/series-m2-12r/

III. AD should try a Benchmark power amp to determine if its relatively distortion-less sound quality is really unsatisfying.

IV. If the reviews in Stereophile are meant to be just a form of entertainment, rather than serve as something of a buying guide à la Consumer Reports, then why is there a semi-annual listing of recommended components which ranks their sound quality in various classes?

Awsmone0's picture

Yes there do seem to be so contradictory points, but maybe Stereophile is a broad church

Entertainment, consumer information, tech measurements and subjective articles

Steve Guttenberg made a point that the sound engineers want devices that are transparent as possible, but then they often add distortion to mixes ?

There are a whole suite of devices that do that, and also in live play various distortion devices that can be foot activated to add different distortions

I think the transfer function may be more important than the actual measurement of each distortion harmonic

The Lamm is a classic example as is the Pass labs both of which are known for their “musicality”

Herb Reichert's picture

"the transfer function may be more important than the actual measurement of each distortion harmonic"

the feedback/feed forward/degenerative corrections required to achieve low THD numbers are a case of the cure being worse than the cold (why not use linear devices in the first place?)

just saying

hr

Herb Reichert's picture

the Benchmark AHB2 drive the RAAL SR1a pure ribbons as I type these words

hr

JRT's picture

I would like to hear that combination of Benchmark AHB2 driving the RAAL SR1a in comparison to my Audeze LCD-X. One thing that I like about my LCD-X and my LCD-XC is that they not only sound pretty good, but are also easy to drive.

The RAAL SR1A ribbons need a good power amplifier suitable for driving loudspeakers. My AKG K1000 headspeakers need the voltage swing of a loudspeaker power amplifier, but don't draw the current. I expect that the SR1A has lower linear distortion than the K1000, but the K1000 can be positioned out in front of the ears to provide better soundstage presentation than anything else that I have tried.

The guys who engineered the K1000 have more recently engineered the Mysphere 3.1/3.2 headspeakers, which also can be adjusted well off the ears and forward. I would very much like to hear those. Pricing on those Mysphere headspeakers is uncomfortably steep.

Bogolu Haranath's picture

As a side note ....... Positioning headphones 'angled in-front' of the ear pinnae may not work well with all types of music ....... It may work 'satisfactorily' with 'some' classical music recordings ....... The idea is to mimic HRTF (head related transfer function) ........ But that type of headphone positioning cannot successfully mimic ITD (interaural time difference), which we all hear when live music (sound) is played ...... Sony also makes some of their top of the line dynamic headphones with angled drivers ........ With music like pop/rock for example, the sound could be 'weird' :-) .........

JRT's picture

https://www.innerfidelity.com/content/smyth-research-realiser-a8-processor-and-headphones

https://www.innerfidelity.com/content/canjam-socal-2018-smyth-research-realiser-a16-headphone-surround-system

The convolution in that corrects for individual HRTF and provides linear equalization of the headphones. But it still only provides the sound of the replicated array of loudspeakers playing in the replicated room. Those can be very good loudspeakers in a very good room, eg. a sound stage at Skywalker Sound, but that is not the same as hearing John Coltrane playing live from a good seat at the Village Vangaurd.

A very different convolution on some sort of ambiosonic data set would be needed to transport the listener to a replication of listening to the music played live from the best seat in a concert hall or other suitable venue.

Bogolu Haranath's picture

Agreed ....... See my comment below, in reply to your comment :-) ........

Bogolu Haranath's picture

Listening to 2 or more loudspeakers can mimic HRTF, much more closely :-) .........

Bogolu Haranath's picture

It is possible in the future, some type of DSP could be employed for successfully mimicking HRTF in the headphones as well :-) ........

jeffhenning's picture

Not quite sure what to make of it since there didn't seem to be much of a cogent argument/premise put forth. Is this Art's "Network" Howard Beale moment? Should we shout out of our windows?

I'm struggling to find a coherent thread through this rambling mess. OK, though, I guess he was really fired up in more ways than one when he wrote this and that's fine as well as entertaining.

Art, though, I wouldn't make this a habit.

To expound on what I think was a general part of his diatribe and create my own:

• Testing equipment is part of this publications heritage. When Stereophile stops testing equipment, I'm assuming that the magazine, the industry and humanity are doomed.

• All reputable manufacturers test their equipment and publish specs. Those that don't may be selling snake oil ($3K USB cables?).

• Testing equipment is the only way to verify if what they are selling is truly worth the price

• Art, I'm sorry that you can't comprehend the digital world we now encounter, but let's try: disregarding the SNR and THD of the electronics past the DAC in a digital playback device, there is an inherent amount of of noise in both the signal and the DAC decoding the signal. 16 bit audio has 65,536 possible levels from 0dB down to 96dB (or so). Below that, the audio signal clips to black and the only thing left is the quiescent noise from the components. Due to things like dither and other processes that may be going on in the chip to keep the lower bit range linear and well behaved (for the price of the chip used, mind you), noise will be created. If that chip is actually meant to get a 24 bit signal (16,777,216 possible levels - 256 times 16 bit, which all them are now) and gets 24 bits, then, that chip can run free of any noise producing processes that are needed to optimize a lower bit rate. I know there is a lot more to this, but I think/hope I have this right. If you are a DSP engineer, cut me some slack. I could be wrong, but I hope this is close.

• As a guy who's done a bit of real recording in his day, I agree with the people in the industry (recording & audio) who think that there is very little room left for improvement when it comes to electronics. That's what Bruno Putzeys said when asked why he designed the Kii3 speaker. Didn't stop him from making a better amp than his previous nCore, but whether the difference between an nCore and a Purifi is audible under most circumstances is highly questionable.

• The bottom line is still this when it comes to audio reproduction and has been for a while: how good are the transducers at the beginning and end of the transmission chain? And, then, the room at the end of that chain used to listen to the signal? It's as important as the transducers. Everything else is several orders of magnitude less importance. I'm not saying that proper power filtering and cables that neither emit or accept EMI are not valuable, but if your room, the speakers and the mic's used to record the audio suck, there is no happy ending.

• If you don't listen to your music in an anechoic chamber a 100 feet below ground, you will be quite lucky to have an environment where the background noise is 30dB. That means that, at best, the SNR of your listening environment is 80dB (if you listen to music at hurtful levels). I know, yes, we humans have great alacrity to hear stuff below the noise floor...ain't that wonderful! If you think, though, that you need and amp with greater than 130dB SNR + THD, you are kidding yourself.

• If you've spent $40K or more on monoblocks that weigh 100lbs each and have very sketchy specs, you have wasted a ton of money.

• Benchmark and Devialet's stuff have already been tested and proven to be better than anything else. I'm looking forward to seeing what happens when the latest Bruno Putzeys design (the 1ET400A amp module) hits JA's test bench. That will be very enlightening.

• Personally, I find the culture of equipment lust without verification that said equipment is any good quite disgusting.

Circling back around to my point: Some of the mega-buck stuff out there is truly worth the price and that only applies to speakers below $210K (Rockport Lyra). If you are paying $20K for a piece of electronics, it better be the most kick-ass pre/pro ever. The best amp in the world is $3K... the reason it's so great is that it's as good or better than anything and costs $3K (100W stereo/300W mono). What else do you need?

If you can't figure out why young people don't care about being audiophiles, four reasons (other than audio nerds being exceptionally annoying):

• They are technically savvy and when they see geezers gushing over mediocre, megabuck equipment the whole thing looks incredibly lame... to the point that those people seem certifiable

• The day of the "stereo" system is over for anything save music in your bedroom, kitchen or home office... and those aren't for serious listening, but they could lead to it with high value equipment at budget prices. Luckily, that seems to be a growing sector in the market.

• Most kids today listen to music on their headphones (which can be at too high a level). They will eventually want a system that's not attached to their head so offering that system that also sync's well with their phone will be good. Savvy manufacturers are already doing that (KEF, Klipsh, B&W).

• Sorry to say, but when I was a kid in the 60's, music was a movement as well as entertainment. It was truly important in sending messages to people across our country as well as a good bit of the world. It no longer carries that importance to the youth of 2019. It's been happening for decades so I'm not pissed off, but, music to many kids now is like the latest confection they just savored (that's nice...gone...next!). In the late 60's/early 70's, there was still good pop music, but there was also a big undercurrent of discontent that got radio play and TV time. Owning a stereo meant you could hear it loud, enjoy it, and let your neighbors hear a bit of it, too. It might catch on with them. Music meant something then. It did something then.

And, having a really kick-ass system to play that music (especially at parties) was important in more than a few ways.

Sorry for bringing everyone down.

Yes, I swerved, but hopefully, my stream of consciousness has been more coherent. I figured if Art could do it, why not me?

I love listening to and making music!

And to all, a good night! (MoFo's)

Feel free to create your own diatribe about my diatribe! Let's crash this server with diatribes!

Awsmone0's picture

Steve Guttenberg made an interesting observation recently

He went to RMAF and then AES

He pointed out the sound at AES was universally terrible as it often has been in the past
At the audiophile show although patchy, there was a lot of good sound

It’s not true that sound engineers aren’t adding distortion, otherwise why are there an enormous number of patches including analog simulated patches

Something is lost in recorded music, more so digital
I understand it’s engineering excellence I was an early fan, but if I put up digital versus analog versions of the same material unfortunately the analog version usually wins, I wish it wasn’t so I really do, engineeringly dragging a rock thru pvc with it’s makeshift way it has been developed should be trounced and crushed by digital, but it actually isn’t and well that’s an interesting observation

Some of this is a bleaching of the timbre and dynamic compression in recording process

But

Some transfer functions of amplifier appear to recreate the timbre more than others

This seems to relate to a specific ordering of the harmonic spectra and not directly related to percentage of distortion, but the distortions “palette” so to speak

My hypothesis is certain amplifier “palette” seems to alleviate the bleaching of the recording process, making instruments sound more real
You might argue this isn’t accurate, well neither is the recording engineer adding distortions, or using the Haas effect, or doubling up tracks, or moving instruments around in the recording space, or equalising
Ultimately audio reproduction is an entertainment not a scientific pursuit of purity to the sound, otherwise we could robotically not have sound engineers nor mastering engineers who all would be replaced by algorithms to sonic purity
I don’t want my system to sound like the microphone feed, but real instruments , there are others that want AHB amps, and hopefully they enjoy what they do to
Having heard Bruno’s amplifiers, I had rather I hadn’t I would have maintain more respect for him, great engineer I am sure, genius, and he has made quality amplification cheap for many people, and that’s a noble end, but not the last word in my view
Finally
I am also not sure that modern recording engineers are really moving forward, given the plethora of highly compressed jangly sounding rubbish they are producing these days despite incredibly transparent DAW etc

As to amplifiers, well yes the trivial exercise of getting a amplifier to measure well, is pretty old technology, and was possible in the 70s, long before Bruno

Unfortunately getting an amplifier to sound good is another matter

As a guy who went on measurements and purchases for many years , I wasted all that time, because most don’t sound very good
Getting an amplifier to sound wonderful is a combination of science and art

If you think static frequency measurements are all there is, I wish it were that simple.....

jeffhenning's picture

... has not been the same.

What you have been listening to is very poorly engineered music that's been overly processed. Like food, the more you process it, the less you get from it.

As to what you are hearing with amps, I can only speculate, but the truly great stuff made today for $3-6K is transcendant when used in an active speaker, but can still be fantastic with stone-age passives.

As to "getting an amp to sound good", that has a Sh#t-ton do with the crossover in the speakers and its drivers.

Passive speakers are both highly reactive for a single amp & obsolete. There is not one loudspeaker today that cannot be improved by ditching the passive crossover and going multi-amped and DSP'd.

The reason that isn't done so often is the same reason that the Porsche Cayan Turbo S is so expensive... It's only for the sexy people! But, it is trickling down soon.

And, oh, yeah, because most HiFi consumers are either buying into the status quo about passive speakers (which they don't truly understand, but have bought into) or they are dolts, powered speakers in Hi-Fi are poo poo'd. The people doing that are of very questionable intelligence.

Going on measurements is not a bad thing if you understand the measurements. Perhaps, you do not.

As to amps, if it's very close to load invariant and all of the noise and distortions are -130dB down from full power and that amp is from 100 to 200 watts, that is a great amp. That is world class. There are, maybe, 3 that fit that bill. They are not more than $6K for a stereo version.

As to your last assertion, no, I know that is not all there is to an amp save it measurements... you are making an assumption.

Here's a thought for you. Do some googling on THX AAA amp design and Benchmark AHB-2. Do a deep dive. The AHB is the cheapest amp in Stereophile's A or A+ amplifiers. John Atkinson is no chump. That amps distortion and noise are so low, it tested the limits of his machine.

Before the amp was officially put for sale, I found out about it, contacted John Siau of Benchmark, and he sent me a bunch of measurements and wrote at length about the amp and how difficult it was to use the best equipment in 2013 to even measure the amp. I actually forwarded that to JA.

To get accurate distortion measurements, you would have to do at least 16 runs to cancel out background noise. That was because the distortion and noise were so low that the machine used to measure it could barely find it on a few runs (more samples offered greater accuracy when staring into dark... just like the Hubble). John Atkinson says that in the review.

Two more reasons that you know the Benchmark AHB-2 is great:
• You can't find anyone selling used versions on line...at least I haven't and I've tried
• They are regularly out of stock on their site and offering a date for new ones to arrive so...

...People buy them, don't want to sell them and the company has a backlog, but never gouges their potential customers.

What would you make of that?

Awsmone0's picture

What you have been listening to is very poorly engineered music that's been overly processed. Like food, the more you process it, the less you get from it.

Agreed most modern sound engineers are not producing high quality despite supposed technical transparency

And, oh, yeah, because most HiFi consumers are either buying into the status quo about passive speakers (which they don't truly understand, but have bought into) or they are dolts, powered speakers in Hi-Fi are poo poo'd. The people doing that are of very questionable intelligence.

I use active systems agreed ?

Going on measurements is not a bad thing if you understand the measurements. Perhaps, you do not

I am happy to discuss any aspect of measurement
And the maths and engineering behind it ....are you ?

Simple question ?

Calculate the transfer function of the following

Lamm m1.2

Pass labs 200.8

Ypsilon Hyperion

Benchmark AHB

You mention JA and I don’t disagree how well have his measurements of the AHB they are impressive

BUT

that is not the amplifier that’s his reference

Oh dear

It’s a

Lamm m1.2

With a certain transfer function

Oh dear oh dear

Bogolu Haranath's picture

It is called HRTF (head related transfer function) ........ Like they say 'it's all in your head' ....... Just kidding :-) ......

JRT's picture

https://www.innerfidelity.com/content/smyth-research-realiser-a8-processor-and-headphones

https://www.innerfidelity.com/content/canjam-socal-2018-smyth-research-realiser-a16-headphone-surround-system

Bogolu Haranath's picture

Yes, I know about the Smyth Research Realiser ....... I read those articles before, especially the InnerFidelity article, which is more recent ....... The new Dolby Atmos application for headphones, may also do similar function, especially in 3-D sound intended for music, not for movies ......... Sony and DTS are also trying that application for headphones :-) ........

Herb Reichert's picture

You just said what I've wanted to say since I started at Stereophile; and you said it better than I ever could. My hat is off - thank you!

It is so good it must be repeated for emphasis:

"But

Some transfer functions of amplifier appear to recreate the timbre more than others

This seems to relate to a specific ordering of the harmonic spectra and not directly related to percentage of distortion, but the distortions “palette” so to speak

My hypothesis is certain amplifier “palette” seems to alleviate the bleaching of the recording process, making instruments sound more real"

Your "hypothesis" correlates perfectly with my 100 years of listening.

hr

Ortofan's picture

... choice between 'pleasant' and 'accurate' sound quality.

Are certain amplifiers (with their inherent transfer functions) truly better at recreating instrumental and vocal timbres, or are they creating a certain effect by enhancing the reproduced sound quality in a subjectively appealing manner by adding specific distortions to the signals being passed through them?

Is reproduced sound quality that is perceived to be more pleasant possibly being mistaken for being more accurate?

Glotz's picture

Is this why an tube-rectified preamplifier may sound more pure than a solid-state rectified one (yet hold higher THD overall)?

Is this why some of these preamps have a bold, colorful midrange while they measure demonstrably poorer (not considering frequency response deviations from 'flat')?

I look forward to your continued journey in this area, man!

This is "good forum"; people contribute and the discussion leads to new understanding down the road!

JHL's picture

Oh I don't know; I find ponderous objectivism a reliable bellwether of whatever it is they're always on about.

jeffhenning's picture

After going back into this rambling mess, as to point 1:

In a playback system , distortion is anathema. It is a veil covering the original intent of the artist and his engineer. It offers nothing, but a distortion of their true intent for the recording.

If distortion is added to a single instrument to make it stand out, that is gigantically different from adding it to the whole recording.

In the past, as an engineer, you had to realize the limitations of the media, the playback systems and make decisions to "improve" the sound of the end product by bastardizing your studio master and sending that wretched piece of dung to the pressing plant.

As artists, we no longer need to do that with hi-res digital. The consumer can buy a perfect copy of the studio master on Blu-ray or from sites like HDtracks.

Why do you think that adding less clarity to the end product is anything close to a good thing? That, from the artist's standpoint, is insane. Who nominated you to be my recordings engineer?

The distortions done to ancient sculptures and buildings are not the least bit analogous to audio. If you are of that impression, you are drastically mistaken.

RH's picture

I enjoyed that column! But then I enjoy most of Art's writing, even when I don't agree with the content.

I remember Art once started an audio column with the line "Consider the coelacanth."

I laughed, it stuck with me ever since, and I thought to myself "any writer who can start off an audio column with that line, and make it work, has earned my attention."

Bogolu Haranath's picture

"I'm mad as hell ...... I can't take it anymore" ........ Howard Beale :-) .........

jeffhenning's picture

Art, I have no bone to pick with you, but when you start spouting some BS that having more distortions of any kind in your playback system being what high fidelity is about, you have lost your way.

Sounding good and high fidelity to the original recording are two different things.

If non-linearities and distortions are part of what you are promoting now for the end of the listening system, well, that's just sad.

By the way, Nova had a great show on the Acropolis several years ago documenting how the Greeks slightly distorted everything they built (Parthenon, Pantheon, etc.) so it was more pleasing to the eye. A little bulge here and there made it seem straight rather than concave. It's a visual trick.

Again, not even close to audio.

I've used band-limited distortion to make make a bass line sound more prominent in a mix and the strange part is it made it sound cleaner and more present than using just EQ. It tickled the ear differently.

In a mix with a half dozen vocals, a full drum kit and a bunch of synths, that trick of the ear is not surprising.

That can never work on an entire mix (unless the mix is S##t) and still the results will be substandard.

Your assertion is nonsense. If you have a truly top notch system and the song isn't sounding so good or as good from else where, it's because the recording sucks. Nothing else to say.

All the best,
j

RH's picture

I believe you have misinterpreted what Art was saying.

I did not see him saying 'Distortion is high fidelity.'

Rather, he was pointing out that audio systems (speakers in particular no doubt) have some level of distortion so we are in a "pick your poison" scenario. He was careful to make clear that by "distortion" he was not simply talking about fidelity simply to the recorded signal but in the path from the thing being recorded to it's reproduction in our system. That's why he used the piano example. A sonic reproduction system with "zero distortion" would produce a piano in my small listening room at the live levels and acoustic power of the live event, which isn't what most of us would actually want (and would sound bad in many homes. Similar to the fact that in setting up a home theater we don't REALLY want perfect fidelity to the sounds happening on screen - that would mean we'd go almost deaf watching the next war movie!).

So for instance one may perhaps desire a speaker that adds a bit of body to the sound so that a piano recording listened to at acomfortable-to-that-person's volume will sound more satisfying and "believable" rather than obviously too diminished. Again, as Art says, the type of characteristics that he might seize on may not be the ones you favor.

So try to meet Art where he actually was being careful to place the conversation.

And, if for a moment more I can hopefully interpret Art's position correctly: He's pointed out before that some people get hung up on some parameters of "neutrality" while forgetting others: e.g. a system may measure nicely neutral on axis, with good off-axis behavior, but may not convey the dynamic realism (a form of fidelity to real life sound) of a system that may not measure as well in the frequency domain.

If you have a truly top notch system and the song isn't sounding so good or as good from else where, it's because the recording sucks.

What amounts to a "top notch system" will vary between audiophiles. Your "top notch system" may not be mine. Or Art's. I have listened side by side with someone else to a very expensive set up, highly lauded speakers, and they swooned while I was unmoved. Meanwhile, I come home fire up my little tube amp hooked up to a pair of modest speakers and I swoon to the sound.

Nothing else to say.

Well, there is more to say. Fortunately, there are others to say it ;-)

JHL's picture

Excellent. What you point out pertains to real audio and not the usual objectivist posing: Although it's safe standing atop the simplified absolute while hoping to win a rhetorical point, in the end the objectivist probably isn't as much about good hifi as much as he is preventing your version of it.

Among many other things, two stand out when I read your comment. The first is that the *spectral distribution* of distortions is Audio 101 more so than the absolute level thereof; and the second is that reproducing a presumably live piano in a space is, in addition to being impossible, likely to be undesirable. After all the stereophonic illusion depends on spatial context - even if it is itself a distortion of types - within which we'll perceive the original hall or studio as well, that being much of the point of the whole thing. After all, great hifi is a multi-sensory time machine of sorts, pursuant which any number of hardcore, technical recordings, being over-miked, fail that crucial test of context.

The goal shouldn't be to acquire X Minimum Bandwidth, Y Sound Pressure Level, and Z Acceptable Distortion - despite the assumptions objectivist technophilia seems forever freighted with - nor can it reconcile your space with the context of that original space, a realization that seems to fail to dawn on some of us convinced that the room is itself the second most crucial element in the system.

I tend to doubt reproducing Carnegie in full cry is something even they would want in their basements and apartments...

wilco's picture

Recordings, Masterings, Re-Masterings-- that Suck.

Beyond all our obsessive ditherings and meanderings about components, it's the Source material, whether on CD, LP,Tape and Stream, that determines 99% of the sound quality we so desperately seek.

Yes the Room and Speakers predominate the sound from a particular source, but a bad recording will always sound bad, and usually worse with revealing Electronics, Speakers and Room.

Fortunately there are some good Jazz labels: ECM is uniformly well recorded. Classical quality is wildly erratic. Pop/Rock/Alternative is usually awful. The audiophile's challenge is searching out the good recordings.

davip's picture

What is it with Stereophile staff-writers and attacks on Edgar Villchur? First there's Herbert Reichert (https://www.stereophile.com/content/harbeth-monitor-302-40th-anniversary-edition-loudspeaker) who thinks that Villchur, by introducing the Acoustic Suspension speaker, "...ruined audio"? Reichert, in his review of the ~ £7k ported Harbeth, apparently heard "...a distinct drop in energy between 80 and 100Hz, followed by a rise at 63Hz", but didn't seem minded to note that Villchur's $100 AR18s is flat right through that audio band and only falls off at 12db/oct thereafter -- something that's apparently beyond Alan Shaw's 50x-more expensive pretty-box. Now, Arthur Dudley takes the same tack, suggesting that the relative absence of AS loudspeakers and suspended-subchassis turntables (another Villchur first) today is somehow reflective of their lack of worth despite the fact that the honky ports and motor-bolted-to-the-plinth of their ported and unsuspended replacements make room-matching a nightmare and produce so much motor noise as to make the turntable 'sing along' to itself.

Would this be the same Herbert Reichert who described (https://www.stereophile.com/content/gramophone-dreams-14-rega-planar-3-page-2) putting that stethoscope on a number of solid-plinth contemporary turntables and found that they communicated so much motor noise to the tonarm/cartridge that the identity of the music could actually be determined from the stethoscope alone where the suspended-subchassis examples (the Linn and Roksan) produced silence? Why manufacturers do not use this model anymore is because it's cheaper and easier to bolt a motor to a piece of medium-density fibreboard than it is to properly engineer a tuned subchassis.

Similarly, would this also be the same Arthur Dudley who states in regard to the Linn (https://www.stereophile.com/content/listening-26-page-2) that "...Given the choice between disturbing the relationship between stylus and groove, and displacing the suspended components as a unit, even if only temporarily, I'll take the latter any old day? Does he now think that 50 Hz motor-noise propagating around the whole turntable is Not somehow "...disturbing the relationship between stylus and groove"?

Have some consistency in your writing the pair of you as you're on record with these inconsistent views. If you think that "...the majority of turntable manufacturers have decided (that) it's much easier to achieve the results they seek, and to ensure consistent and reliable results in the field, via other means" then you're presumably ok with that consistency being the fundamental compromising of phonographic fidelity through intrinsic motor noise.

Let's set the record straight on Edgar Villchur (again). This would be the same EV who revolutionised loudspeaker design through invention of a system that provided 100s-of-1000s of music lovers with the first affordable taste of truly high-fidelity in the AR18 (that still runs rings around any sub-$1K ported-dog today). This is the same EV who developed the industry standard for hearing aids, the same EV who made usable audio for the partially-sighted and the blind, the same EV who introduced progressive employiment practice into audio manufacture and, like Joseph Grado, would repair your purchase no matter how old usually for free, and the same EV who eschewed patenting to allow anyone who wanted to to use his revolutionary hearing-aid system to do so for the benefit of all. Finally, of course, this is the same EV who developed the first truly high-fidelity turntable that isolated the platter and tonearm from the motor with a sprung subchassis that formed the template for Linn and others (and that most companies apart from Linn and SOTA today ignore in their motor-bolted-to-a-piece-of-plywood rush for money).

The pair of you should have some bloody respect for this giant of the audio world and humanist; EV contributed more here than two audio scribes will ever do in a hundred lifetimes.

Glotz's picture

I was a bit confused on why this column focused on Villchur... a lot of it is tongue in cheek?

But if the Magico S-5 mk2 is testament to the greatness of acoustic suspension designs (much is written about their prowess, notwithstanding the massive cabinet design to control inefficiencies), then why walk away from the example in the argument? You instead focused on 2 older, less sophisticated designs that suffer from said acoustic suspension issues.

Or are you again saying there's still brilliance in what is old? Like the idler-wheel turntable's greatness within drive, force and rhythm? Or are you just reminding us of the new question you pose..?

While other magazines have asked similar questions about distortions, I cannot think of a better writer to start another critically important conversation to ask in what sort of setting and to what type of listener do X's component distortions matter (HR included). This is needed in context of all measurements, and shows itself in almost every review of this magazine.

To the unseen argument this month, the most important measurements I care about most in my system are input and output impedance, and JA1 is almost always sure to include that at every chance (at least as a caveat).

But it's one of the most important measurement observations he can make as Technical Editor! If my solid state amp evinces 'distorted' (huge deviation from general, FR neutrality) sound with the preamp its partnered with, I will look to a mismatch there first and foremost. And that massive distortion is a conditional one!

As well from a consumer standpoint, this is a mandatory purchase condition I need to listen through with my amp, regardless of how amazing the preamp measures, otherwise the mismatch causes massive issues throughout the chain (far outweighing any THD distortion levels).

This relegates me to less choices in the spectrum of the market, hence my need for all of you and your ancillary system choices, as well as your critical comparisons to other competing components. AND measurements.

Lars Bo's picture

there are others to say it ;-)"

Indeed. And do let them be only human a lot. And musical. Thanks.

rl1856's picture

AD- I read your column (as I do each month) and I found myself raising an eyebrow or two at several points. You voice your displeasure for Acoustic Suspension designs by implying the science may not work. You also criticize suspended sub-chassis TT designs. In both cases you rest your claims on the canard that the market doth speaketh. (Setting aside the fact that McDonald's sells more burgers than any other vendor).

In regard to the science you state that distortion rises when efficiency falls (please correct me if I misread this point). Historically, AR bass response was universally praised, and still is, for extension, definition, and low distortion. In fact AR speakers had less LF distortion than Klipsch speakers at equivalent frequencies. This came at a price as you correctly pointed out- more power was generally needed than for more efficient speakers. You seem to imply that Mr. Vilchur introduced his speaker at the dawn of the SS amplifier era. The AR1 was introduced in 1954, 7 years after the invention of the transistor, and about 10 years before SS amplifiers were market viable. The only high power amplifiers generally available at the time were McIntosh MC60, Dyna MK-II and various theater amps from Altec and RCA.

You noted that there are few speakers made currently using AS principles. I think this is because of how the market has changed and how the economics of speaker production have changed.

Back in the day, AR speakers were heralded because they were so much smaller than horns (monkey coffins....), and seemed to be a better fit in a domestic home. Now the reverse is true. Most listeners value imaging, and at least moderate efficiency, along with a smaller footprint; attributes generally not associated with AS designs. AS speakers were smaller than the horns and boxes they replaced, but are much larger than the monitors etc that have in turn replaced them. A noted speaker designer, who worked for AR, and other speaker companies, pointed out that reflex loaded designs are now cheaper to produce for similar performance. Size, and the cost of a large, heavy, rigid box likely are key considerations. But the science still works.

Suspended sub chassis TT are complex and costly to produce. The basic AR design was revolutionary at the time, and led to 2 significant product lines: Thorens TD series, and Linn LP12 series. BOTH are highly regarded in the new and used markets. OTOH it is much cheaper for a company to create a rigid plinth, then bolt on a motor and tonearm rather than commit to the expense of designing a properly engineered suspended sub chassis product. Cost, not performance is likely the reason. If performance were the sole reason, why are listeners paying premium prices for used AR, Linn and Thorens tables ? Why is there a thriving after market to supply restoration parts for these tables.

Also- I have met a lot of people who were reared in WV, and have full sets of teeth !

Ortofan's picture

... sold modestly priced belt-drive turntables with floating sub-chassis.

The Pioneer PL-112D/PL-115D/PL-117D were essentially entry-level models, so were quite affordable. The least expensive PL-112D had a list price of $100, which would equate to about $450 today.
https://img.audiofanzine.com/images/u/product/normal/pioneer-beltdrive-pl-112d-217204.jpg

A few years later Yamaha brought out the somewhat higher-end PF-800/PF-1000.
The less expensive PF-800D had a list price of $450, which would equate to about $1,100 today.
http://www.thevintageknob.org/yamaha-PF-1000.html

Bogolu Haranath's picture

"you can't handle the truth" ........ Jack Nicholson :-) ........

Stephen Mejias's picture

Exceptional thinking and writing, as always, from Art. But medicine and mixed drinks -- aren't those the same thing? ;)

JRT's picture

I have not yet seen one word written by you about attending.

Are you perhaps not going this year?

http://capitalaudiofest.com/schedule/

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