Slow Listening

Subjectivist audiophiles have long maintained that long-term listening is necessary to assess the quality and character of an audio component. Scientific testing methodologies such as ABX, which require quick and conscious evaluation of a change in the sound, have long struck many of us as insufficient, seeming to miss much that affects our enjoyment of music. A pair of Genelec researchers—Thomas Lund, an audio professional with a medical background, and Aki Mäkivirta, a research and development manager and a Fellow of the Audio Engineering Society—have published two articles (footnote 1) on the science of hearing and perception, and their findings appear to support such views. Among their observations:

  • The "perceptual bandwidth" of humans—the maximum size of the [sound] datastream into our brains—is remarkably small. Experts put it in the range of 40–50 bits/s: compare that to the worst kind of MP3, which has a data rate of 10s of kilobytes/s, more than 1000 times larger (footnote 2). (No wonder we're easily fooled by lossy encoding.) Perceptual bandwidth "should generally be considered a scarce resource," the authors state.

  • We are not passive recipients of sensory information—how could we be with such a low perceptual bandwidth? Sensing is an activity; attention is a tool we deploy to select which information we take in.

  • Only a fraction of the perceptual information we take in is available to our conscious awareness; much of it goes unnoticed. Yet, it still affects us. We—or anyway our brains—even solve problems—unconsciously—using unconscious information.

Together, these ideas imply a perceptual landscape far different from the one that people long assumed: Through long experience, we build an internal model of reality and then reach out to test it against scarce, select sensory input. Our ability to function well and make accurate judgments depends on the accuracy of our internal model and the precision with which we correct it with scarce, carefully selected external stimuli (footnote 3).

Models of reality are contextual: An outfielder's long experience allows him to get a fast start in the right direction when a ball leaves the bat. Our own long experience allows us to detect small changes in what we hear that others cannot (footnote 4). A major theme of the articles is that listening takes time. Indeed, the titles of both feature the phrase "Slow Listening"—surely an allusion to the slow food movement that started in the late 1990s (footnote 5). Time matters in subjective listening tests, the authors conclude, in various ways:

  • Music and language training over years affect our ability to detect short, transient sounds.

  • Becoming familiar with a reference audio system takes time. "Based on a limited perceptual bandwidth and 8 hours of dedicated listening per day, getting to know a room and equipment in any detail would take at least a week, but assuming years would be safer," the authors write. "Subjective tests, even producing repeatable results, may have little relevance if confined in time"—a challenge for audio reviewers for sure.

  • Much that matters in perception goes on below the surface, without our explicit awareness. How do we know when our unconscious rumination has matured to the point that it's time to render judgment? We can't, so we need to factor in extra time.

What, then, are we to make of ABX tests in which test subjects compare a version of a few seconds of music, jangling keys, or whatever against a reference? Such tests are good for many things—see this month's Industry Update—but far from the last word on sonic and musical significance. When we rely on them too heavily, we miss things.

Here's one more idea from the article that many audiophiles can relate to. The authors cite an article published in Nature Neuroscience in 2014 that establishes that noise well below the threshold for physical damage can cause auditory stress and impact our hearing. Nontraumatic sounds, including those with "excessive high frequency energy, lack of 'quiet transients'" (which are removed in lossy encoding schemes) and "interaural strangeness or unnaturalness," can cause undesirable changes in the "auditory brain," even if they do not damage hair cells. Aural stress, listening fatigue, and the resulting impairment in our ability to discriminate small differences is familiar to audio reviewers. Scientists have now corroborated our subjective experience.

Which raises another possible objective of audio systems. Accuracy—fidelity—is, for most serious listeners, the benchmark we measure our systems against, whether we measure fidelity by objective or subjective criteria. But other valid criteria exist. Maybe some listeners just want sound that minimizes, or even alleviates, stress, whether through second-harmonic distortion, suppressed response in the presence region (aka BBC dip), natural interaural relationships, or whatever. Maybe some people just want their sound system to sound good.

Speaking of sounding good: This month's issue contains the first installment of a new Stereophile column. In Revinylization, Art Dudley reviews the most important of the latest reissues on vinyl. You'll find the new column on p.125 and here.

Footnote 1: The company's managing director, Siamäk Naghian, is a coauthor of one of the articles. See here and here.

Footnote 2: I find this number implausibly small, but it's what is claimed.

Footnote 3: John Atkinson discussed this subject in his 2011 Richard C. Heyser Memorial Lecture to the Audio Engineering Society.

Footnote 4: It's not only reviewers of course; anyone with good hearing and the right mindset can acquire such skill.

Footnote 5: Later, there was also a brief "slow listening" movement, a response to MP3 and earbuds.

jimtavegia's picture

I think our ability to concentrate is what causes all the problems. We do it in audio and in normal, everyday life.

How often do we fail to hear key ideas in a conversation only to have to have someone repeat themselves? We really didn't start truly listening at the beginning of the conversation. How easily distracted we are. Did we make a prejudgement about the speaker's value?

The fact that when reviewing loudspeakers we talk about how "revealing" one model is over another. Mastering Engineers must truly be able to concentrate for long periods of time, and then be able to discern whether that tweek to a music file is better or worse and quickly hit "undo".

I think that true audiophiles really just listen and do not do anything else on occasion when really making an effort to listen "deep" in the music. I also think that not only does one have to make a commitment to listen "fully", but to also try and make a value judgement, often impossible to do, on whether this recording is better than some other one.

Now at 72 I do not trust my own hearing and leave the mastering to others to judge, My HF is gone and for me to think that I can make an honest value judgement would be wrong. I am just glad that I am honest with myself. If someone says that speaker system or pair of headphones is bright sounding, it probably would not seem so to me.

What I find interesting in the writers at Stereophile is that all of their systems are so totally different, and yet they all have made choices on what they think is "best?" or is it just what they prefer? This is truly an odd hobby and often frustrating at times.

MT_Guy723's picture

There are times when I think the hobby has me and not the other way around. Once I started going out to listen to LIVE music, my enjoyment of stereo systems increased exponentially. After that, when I'd hear something in a mix like a ride cymbal struck precisely I would get chicken skin from it. Then I started to have a bunch of musician friends who turned me on to some really good music that wasn't on the radio at that time. I graduated from high school in 1970 and there was a ton of great music coming down the pike every week. I couldn't keep up buying the albums I wanted... but I tried. I've attempted to explain to many people over the years what they might expect to hear if they upgraded their current systems... but they fight it. I just think they don't love music the way I do. Truly, music has been the constant joy of my life - the performances, the recordings, the instrumentation, the artists. Hopefully continuing to learn about its various aspects will keep my mind sharp as I age. I am also deeply grateful to Stereophile and the various individuals who have written for the magazine over the years. For myself, they have been excellent teachers.

John Atkinson's picture
Jim Austin wrote:
I find this number [the range of 40–50 bits/s] implausibly small, but it's what is claimed.

The ear-brain dramatically reduces the rate of information that reaches it during the act of perception. Consider a monophonic 10kHz tone encoded with 24/192 PCM. The original bit rate is 24x192,000 = 4.608 million bits/s. However, when that 10kHz signal is "heard," a single group of hair cells in the inner ear fires - the effective rate of transmission is reduced to just 1 bit of information as the cells go from off to on.

John Atkinson
Technical Editor, Stereophile

Kal Rubinson's picture

That on/off bit carries more information because it's just one channel of a highly paralleled input array. So, when "on" (1 bit of information?), it is signalling the presence of a 10kHz signal. When the adjacent group is "on," it signals and is identified as another frequency.

Only at low frequencies does the hair cell's signalling rate follow the actual external signal frequency.

CG's picture

Isn't this somewhat analogous to wavelet processing?

In our aural systems, it would seem that some "wavelets" are innate through genetics and some are learned at an early age. The same, or more, for "mother wavelets".

So, aside from the obvious physical differences in our ears, there's basic "programming" differences. Which is one reason why people prefer whatever they prefer.

Full disclosure - The above is an amateur's view from studying wavelets and reading Gregory Berns' books... :8^)

RandiO's picture

I refuse to accept this premise beyond its implausibility: Humans' fight-or-flight instinct depends on lightning-fast response to loud noises; first and foremost.
Before this instinct response decision, the brain must first analyze the sound type (danger?), arriving from two different sources.
The brain must then process locational determination by comparing the L/R inputs.
Followed by deciding whether the signal is an echo or reverberation, among many other processing and subsequent decisions.
Since both referenced articles of Footnote#1 are 404, I am going to venture that this stated <50b/s perceptual bandwidth limit is inaccurate. Even if for no other reason than <25b/s PER EAR would make us all borderline deaf and we'd still be making music with tin cans rather MQA or the like.

John Atkinson's picture
RandiO wrote:
I refuse to accept this premise beyond its implausibility: Humans' fight-or-flight instinct depends on lightning-fast response to loud noises; first and foremost.

I believe that is different from the usual processing of audio information, in that the fight-or-flight reflex bypasses the auditory cortex and involves the "lizard brain" ie, the brain stem.

John Atkinson
Technical Editor, Stereophile

Glotz's picture

The complexity and the unfamiliarity (not only something new, but organic vs electronic) of a musical performance also has a great influence on the time it takes to absorb the various depths of its nature.

The issue was a huge one! The PS Audio Stellar Phono, The HW-40, the RAAL-Req SR1a, the Gryphon Ethos and of course, the Benchmark LA-4.

I imagine many readers are waiting to 'sing the joys' of this landmark preamp (or rather fawn over the measurements)! Tubes be damned; the next preamp I buy is probably this one. 'Straight wire with gain', indeed! Lemme guess, you're going to drop the review on Christmas? I bet JA1 has been Santa on Christmas at least once!

RH's picture

On a purely anecdotal level, I personally have not found the need for long term listening to get the gist of an audio system.

I'm reminded of the 4 summers I spent as a Caricature artist at a local theme park in my University years. We did profile caricatures, and I was often enough doing up to 80 or more caricatures a day.

With experience, you begin to recognize certain facial templates, and then whatever deviation from that template sticks out. The speed at which I could process the nature of someone's face increased rapidly to the point where I could literally take a quick glance - seconds - (even someone's face passing in the crowd) and I could produce a pretty accurate drawing.

Though this seems to go against many audiophile assumptions I've found a similar experience in evaluating hi-fi systems. I seem to get a pretty accurate take on the sound of, say, a pair of speakers in a very short time, often a first impression, that remains constant when I'm able to spend much more time with a speaker in various set ups.

In my case when I audition a speaker I will experiment with speaker position, seating positions (far, medium, near-field), listening while standing, while below the mid/tweeters, off axis, even behind.
Once I'm done it seems I have a pretty reliable sense of what those speakers sound like and I can't remember ever being truly "surprised" by the sound of the same speakers when I either take them home, or when I encounter them in other set ups. They are either slightly better or slightly worse versions of the "voice" that was identified quite quickly.

Once I own the speaker, though, it's not like there are many revelations that occur listening over time. But rather, my own reaction to the sound can change to it, depending on mood, or whatever criteria I may be focusing on. If I listen to a friend's system I may come back and either more deeply appreciate some character in the sound of my speakers, or may notice the speaker seems a bit deficient compared to what I'd just heard. The speaker's voice doesn't change, but my attitude towards it may change over time.

Anyway...that's been my experience. I think that, yeah, living with a piece of gear for a long time, and experimenting with it, can in principle increase one's familiarity. But it also seems to me the significance of this can be somewhat exaggerated in the audiophile community, insofar as one can also get a largely accurate impression
in shorter periods of time.

Bogolu Haranath's picture

Are those bell-bottom pants and platform shoes JA1 was wearing in that picture? (see, footnote 3, 'nothing is real') :-) .........

John Atkinson's picture
Bogolu Haranath wrote:
Are those bell-bottom pants and platform shoes JA1 was wearing in that picture?

Platform shoes, yes, but baggies with French pleats rather than bell-bottoms. (I am on the left in the photo at

John Atkinson
Technical Editor, Stereophile

hollowman's picture

On the linked page, the sound quality of your Obie Clayton rip is good. The music makes for an interesting mix with the contemporaries of that day, like Pilot, John Miles, Steve Harley, et. al.
If there are no plans to release it commercially again, you may want to consider uploading it to YouTube or Spotify.

tnargs's picture

So, it's time for Stereophile to trot out one of its occasional series of "Science Proves DBT Results Don't Apply To Recorded Music Listening" articles.

Probably fuelled by mild editorial irritation at some recent comments criticizing the paper-thin logic that Stereophile listening test procedures tell us anything useful about the sound waves being perceptibly preferred or not. How annoying these critics are. How dare they bring this up...again. I thought we shoo'd them away last time.

A bit of very careful cherry-picking, with backs firmly turned to all non-supporting evidence, and Voila! DBT debunked.

Sorry, doesn't hold water. You can do a DBT for any length of time you jolly well feel like, lads. Take a month. Take three. You can call it Slow DBT. The only problem you are going to have, apart from boredom due to the absence of the self-reinforcing feedback jollies that the usual review process provides, is your ever-decreasing ability to distinguish the two sounds as the audio memory fades.

By the way, gents, I'm a subjectivist audiophile, in that I use personal listening to determine what *I* think of the sound of reproduction, and I bet most of the researchers who use DBT to learn about objective reality would say the same. In fact a DBT *is* a subjective listening test. DBT is inherently a subjective approach: that is why the poor *subjects* have to fill out forms!

But the way *you* use the term 'subjectivist audiophiles' is quite insulting to we evidence-based subjectivist audiophiles. We draw a line when it comes to believing wrong ideas that go, "if we perceive it, in casual sighted listening, then it must be in the sound waves." That notion is completely disproven and cannot be supported. But you want to see that 'line drawn in the sand' tromped all over and erased. You want 'subjectivist audiophile' to mean someone with no idea about the general principles underlying the science of human perception; no idea that anything other than sound waves can intrude, and even overwhelm, one's perception of a sound's quality or attributes. Ideally, someone who bitterly denies this fact and will fight it to the death. However, that person is just a subset of the realm of subjectivist audiophiles: a kind of Level 1 Pupil in the category. Better-informed subjectivists want to see some controls introduced into the listening tests, so the tests say more about what the sound waves sound like. Still subjective, but limited to the effect of sound waves.

I believe that the term 'subjectivist audiophile' (and 'objectivist audiophile' too) have been weaponized in the audio discussion space, and I am disappointed to see you use them in that way. Such pidgeon-holing and stereotyping.

P.S. the "findings on perception" in your first three dot points are completely nothing new. They are common knowledge and are decades old, at least, and lie in the area of perceptual processing (more broadly than just hearing or just music). And your interpretation of them is mind-bogglingly naive: I mean, comparing mp3 bitrates with human perceptual chunking, and using that as a basis for questioning the latter? I would normally encourage you to read a little more on the subject before going into print again, but I don't see any evidence that you would do so with an open mind, instead of merely seeking reports that provide validation of closed and predetermined opinions, which can be cherry-picked and plonked before a relieved audience of stalwart gear-buyers. Some of us want better than that.

er1c's picture


Jack L's picture

... all of their systems are so totally different, and yet they all have made choices on what they think is "best?" or is it just what they prefer?" quoted Jimtavegia.

Good question! Most, if not all, audio reviewers judge on how the subject component sound different vs their own 'reference' systems which they are so familiar with.

However, I judge the music quality of any audio by how it brings back the overall music performance - its OPENNESS, depth & width. How I enjoy it "being there" is my yardstick of a quality audio.

How bright, how low it sounds is only personal preference. How 'accurate' its timbers should sound is not as relevant as to how close it should sound with reference to its original OVERALL performance.

I got 1,000+ stereo vinyl LPs, 96% classical music. Believe it or not, my most preferred "reference" LPs are those of the oldest recordings back 1950s or so as they sound so live & so dynamic like attending a live concert vs those in 1970-80s where too much electronic processing was involved during the recording which mess up sound. Even worse are those digitally mastered LPs which sound so tight & so uneasy, so sorta kinda 'artificial' which I (regretfully) own 30+ of them of various labels.

Not easy to guess: I only play tube amplifiers!

Listening is believing

Jack L

Laurence Svirchev's picture

The subject of the column is how to hear the characteristics of components and render critical judgement. Yes it does take years to acquire the ability to hear detail and differentiate between different instruments (the components). Isn't that what musicians do when they choose their instruments? Two decades ago I had the opportunity to travel with an improvising band made of Germans, Austrians, and Americans performing in Europe.
The composer and leader was Georg Graewe. One day in Vienna, we went to the Steinway distributor for Georg to select his instrument. The sign-in book went back to the 1880s, page after page of he great European classical pianists. Graewe spent about 4 hours listening to various instruments; I couldn't tell the differences among them, but he said the differences were huge. When he made his choice, he actually issued further instructions about what he wanted from the instrument,
I also remember.
But to put it at a more mundane level, I was listening to an Ellington recording with a friend and remarked, "the trombone section sounds great." She looked at me and remarked, "How can you hear the difference between the trombones and the trumpets, aren't they the same?"
In both examples, the difference was between training/experience/talent.
In neuro-psychology, there is a concept called 'acquired drives.' Once the new thing is learned and acquired, it becomes 'hard-wired' in the cortical neurons and is subject to ecphoria in the sensory experience.

Bogolu Haranath's picture

It is the same thing as knowing the difference between a good steak and a great steak :-) ......

jimtavegia's picture

I think that parts of the problem are: 1.) Fewer people take the time to learn to play a real instrument, but spend more time on their phones. Imagine if the time spent on a phone was put in music practice. 2.) If you don't know what a real instrument, small ensemble, or orchestra sounds like in concert form, how can one judge anything musical? This sounds this way or that way compared to what? 3.) Studio trickery today leads the way with the fix in the mix and mastering are King. I can't even count anymore the number of ads I get for the newest set of plug-ins for my recording software. I only use a touch of compression and reverb on vocals and never any pitch correction. I feel that I need to practice more learn how to hit the right notes, not cheat. Often I will send a friend a file and see if they can hear the mistake or two I have made. I even remind them to listen hard and tell me what they hear and when they hear it. Often they are just kind I guess and don't want to hurt my feelings. That is not what being a musician or singer is about. It is only about a great performance. A great songs deserves nothing less.

It takes time and money to be an audiophile and then the time to learn what great, accurate sound really is. I think that effort is lost on many who are content with convenience.

I hope you did not miss the PBS Special, Now Hear This, as it was great fun to learn about 4 great composers from those who have studied each of them and then discovered the small differences, in some cases, their works and the different sounds of period instruments.

Since many schools have given up Music Departments it is no wonder we are here. Even my wife and I are so different as my wife of 49 years is such a casual listener and I am certainly not. She is totally satisfied with some very affordable powered speakers on her computer where she listens to music, that don't sound terrible, but a big improvement over what she had. She could care less about better sound, she just wants to hear some songs she likes. I think that is most people.

davidrmoran's picture

Although there is lots of good evidence that fast comparisons are in fact the most revealing, double-blind testing can entail all of the slow listening that anyone wants or would ever want. Why run this straw article now when it has never been the case that DBT requires quick comparing?

MFK's picture

Their training stresses the use of the "Tune Dem" when demonstrating products to customers. A music clip of no more than 30 seconds is recommended. This is antithetical to what the articles imply. However, when comparing a Linn product to one from another manufacturer, customers chose the Linn pretty much every time. This is not to say that the researchers are wrong, simply an anecdote.

invaderzim's picture

I've gone through a lot of changes in amplifiers as well as 'upgrades' with different amplifiers I've built and sometimes when I first listened to the new amp or changed amp I thought "wow, this is it, this is amazing" yet after a few hours or days it would change to "eh, I don't think I like this as much" and I'd switch it back. Or sometimes I wouldn't even realize that I didn't like it as much until later when I'd wonder why I'd cut back on how much time I spent listening to music.

The true test for me has always been when listening to music do I not want to turn it off and am I looking forward to hearing more?

Plenty of setups I've listened to sounded great for a few minutes but after 3+ hours am I still enjoying listening? If I was doing something while listening, have I stopped to just listen? That I can't tell in 30 seconds.

T.S. Gnu's picture

The interesting thing about this is that it also works blinded. In other words, real differences are observable in blind tests.

invaderzim's picture

If our brains did not filter the input we receive we would have a lot of trouble dealing with it. Our minds choose what is important so that we can understand the specific person talking to us in a crowded room rather than always trying to hear all the conversations.

In more recent years they have figured out that a some of the learning disabilities that lead to behavior problems have components where the person isn't automatically filtering the input from the loud and busy world around them so it is overloading them.

With our minds filtering what we actually realize we hear then how do you know what others are hearing in the same situation?

If two people are in the same crowded room a few feet apart but talking to two different other people they will hear different things in that room because their brain is focusing on different input.

Part of hearing 'new' things on old songs when you've upgraded something could just be one's brain actually processing that input because you are focused on it.

hollowman's picture

The "Hard problem" of consciousness is one of the (several) open-ended, heavy-weighted science mysteries -- like dark matter, dark energy, time, etc.

No doubt, when there are better theories about the HP, improvements in sensory science (like hearing) will come in tow.

I don't see much in the "research" mentioned in this article that elucidates on psycho-acoustics and related evolutionary psychology; but the presented *theories* are fascinating, nonetheless.

About ABX and hard-core objectivists...
They are too trapped in the dogmatic conventions of academic textbooks, and related knowledge (as of mid 20th century), to accept FUTURE science. To re-coin a line from The Terminator (1984): "Look at it this way; in a hundred years, who's gonna care?"

hollowman's picture

Hard-core ABX objectivists ... be humbled by NOT KNOWING MUCH ABOUT ANYTHING.
Here are 20:

BTW: I think ABX tests are useful and important for what they can do: MACROscopic testing (audio or otherwise).

Bogolu Haranath's picture

I like question 15 ........ 'When can I have a robot butler'? :-) .........

T.S. Gnu's picture

"About ABX and hard-core objectivists...
They are too trapped in the dogmatic conventions of academic textbooks, and related knowledge (as of mid 20th century), to accept FUTURE science."
Future science is called science fiction. Science is objective, by its very nature. Your fallacious argument doesn’t get more validated by quoting a science fiction (ironically) movie. In a hundred years, we’ll still be objective and blind testing will still be valid...nay, making technological advances.

hollowman's picture

"Future science is called science fiction." It can be. And imagination is important. You can look up a certain quote by Einstein about imagination. But that's digressing!
Let's just focus on audio, and put things in perspective. (And it is THIS that I alluded to in my orig remark).
If I made a comment about CD player sound in the "Letters" section of Stereophile, say back in 1988, I would have been referring to JA's ever-growing list of metrics (measurement parameters). Those have been steadily accumulating, adding to some edifice of digital-audio metrology. Indeed, Specs on manuf. datasheets have evolved in a similar accumulatory way.
In other research, Rob Watts (Chord) claims sonic improvements when his designs are pushed to the limits of what is currently measurable with the AP instrument.
Problem-solving science MUST be viewed with a focused TEMPORAL lens. In other words, this is why colleges require students to buy new revisions of textbooks.

JennMartin's picture

....a guy named Arny is giggling at us!