Machine rhythm: the steps on a Roland TR-808. Photo (CC-BY-SA) Brandon Daniel.

What makes rhythm human? Music technology has introduced machine rhythms, perfectly-calibrated to electronically-perfected grids, yet we know that natural playing is more organic. Or, that is, we know we have certain intuitive preferences. How do those preferences and rhythms really work? And what does that mean for music technology?

Fascinating new research investigates more deeply, using – you know, science!

Here’s the summary of the research itself:

Although human musical performances represent one of the most valuable achievements of mankind, the best musicians perform imperfectly. Musical rhythms are not entirely accurate and thus inevitably deviate from the ideal beat pattern. Nevertheless, computer generated perfect beat patterns are frequently devalued by listeners due to a perceived lack of human touch. Professional audio editing software therefore offers a humanizing feature which artificially generates rhythmic fluctuations. However, the built-in humanizing units are essentially random number generators producing only simple uncorrelated fluctuations. Here, for the first time, we establish long-range fluctuations as an inevitable natural companion of both simple and complex human rhythmic performances. Moreover, we demonstrate that listeners strongly prefer long-range correlated fluctuations in musical rhythms. Thus, the favorable fluctuation type for humanizing interbeat intervals coincides with the one generically inherent in human musical performances.

Hennig H, Fleischmann R, Fredebohm A, Hagmayer Y, Nagler J, et al. (2011) The Nature and Perception of Fluctuations in Human Musical Rhythms. [PLoS ONE 6(10): e26457]

Hear that? One of the most valuable achievements of mankind! (Uh, that makes me want to practice a bit more, as I’m not sure I’d necessarily describe my last gig that way!)

James Postlethwaite, who sends this in, accompanies his news tip with an articulate letter considering the value of the research, so I’ll include all of it here:

Whilst reading the latest issue of the journal Nature (No.7372, Vol.479) I was surprised to se a picture of a TR-808 in the Research Highlights section, featuring research of note in other journals.

The research was about the correlations of rhythmic imperfections in human drummers, which correlate over a longer time period than the random singular imperfections that are inserted by some computer programs. At least I think that’s what it was, as I’m not a mathematician.

I do note that the sample size used in the statistical analysis was only 39 subjects, though the results were of a decent significance. The audio files are available in the supporting files section, CDM has a large readership, t-tests are very simple to run… Just an idea.

It does though serve as a nice reminder that a lot of the tools that musicians use nowadays do have roots in academic research, going back to the days of the early synthesizer. It also reminds me of a comment from a friend who used to own a 909; that one of the charms of this machine was the unique imperfection in the rigidity of the sequencer.
I don’t know if this has been corroborated by other people.

Finally, the piece in Nature magazine seemingly wasn’t written by a fan of electronic music, as it starts: ‘If you have endured much 1980’s pop music, you might agree that drum machines steal the soul from the beat. Their cold regularity is sometimes ‘humanized’ in the recording studio…’. Possibility of bias?

“Endured” 80s pop music? Yes, I’d say that counts as a bit of bias (just on the part of Nature). Imagine reading a story on bee populations, which began “Yeah, Bees. F*** bees.”

But the research itself looks solid and intriguing – and James is asking a variety of other interesting questions, so I’m going to open it up to discussion. Hope this is something we can follow up on. (Academics, attack!)

By the way, a quick search of Nature reveals that the journal regularly publishes material of interest to sound and music – worth noting, as there was a time when that wasn’t true. (Max Mathews was one of the first to help computer music break into the scientific mainstream.)
My search results
And, for example: Rhythmic synchronization tapping to an audio–visual metronome in budgerigars [hint: think tap tempo meets birds]

Updated: Nature wrote a quick blurb: Doctoring the beats
…though it seems from the excerpt that they either didn’t understand or tried to oversimplify the role of rhythmic variation in digitally-sequenced music. The study is, to me, more interesting.

  • I've always thought that it's only a matter of time before programs start using more advanced humanizing algorithms than just white noise. I listened to the sample in the article and agree that the 1/f version sounds much better. Long live automated humanism!

  • robot rhythms

    I actually prefer the electronic beats over human drummers, if you've played with enough humans you can tell how sloppy their timing is, always speeding up and slowing down, extremely annoying. 

    of course midi drifts as does din sync, but those CV guys are usually really close to perfect time. which sounds like music to my ears. 

  • I usually record drums by "drumming them in by hand" on a midi controller, all without quantization. Since I'm a lousy drummer they usually sound a bit weird, but definetly human! And I really prefer that to the mechanical perfection most of the time. There's some exceptions to that, when you want to make the music sound mechanical, to give it a sort of industrial touch, that's when mouse driven drum programming on a gid comes in pretty handy!

    Anyway, interesting research, it corroborates all of my (mostly unconscious) feelings about the topic!

  • FCM

    I'm interested in their methodology, after skimming the article.

    But their terminology "humanized music" looks like a red flag – they're buying into a phrase that sets preconditions for the whole study. (How, how, how can't music be NOT humanized????)

    I realize that the reference is to technology that 'humanizes step sequenced beats', but if they're not going to qualify their adoption of the term, it makes my balls itch.

    I think someone should do an indepth ethnographic study of concerns and questions of the authentic in sequenced music.

    Oh, and what a stupid comment by the journalist… beyond comment. What an ass.

  • FCM

    Here's the article. It looks true, they really said that. Unbelievable.

    Email them here:

  • Peter Kirn

    No, in fairness, what they say is exactly accurate – these features are typically called "humanization" features. But it's of course an oversimplification of what you can do with quantization variations. One of the conclusions is really no surprise – that you would prefer actual human rhythmic variations to white noise randomization applied to a beat grid.

    As for the Nature blurb, no explanation; they seemed not to quite understand what they were writing about, or tried too hard to oversimplify it.

    All of this ignores, of course, groove quantization (manual or algorithmic) that applies specific rhythmic variations that aren't just randomized.

  • FCM

    Here's my email to them:

    "If you have endured much 1980s pop music, you might agree that drum machines (pictured) steal the soul from the beat. Their cold regularity is sometimes 'humanized' in the recording studio by the injection of random deviations from precise timing."

    What is this insulting drivel??

    When I heard that somebody wrote that line, I thought it was from a Cosomopolitan-type gossip magazine, but after visiting your site, it looks like your journal actually resembles something of peer-review quality and even academic approval. So how can you try to slip something like that by? Are your aesthetic criticisms really important in the field of popular music? Do you think it's ok to take a swipe like that because you think all your readers are white, upper-class, classical-music-listening bourgeois who would chuckle and titter at the notion of "humanizing" that plastic fake music made with machines?

    Have you considered for one second, beyond your so-finely groomed aesthetic tastes, that perhaps, people of a lower socioeconomic class might not have access to a lifetime of musical training and equipment, and that these "cold" machines are actually enablers of musical expression that would not otherwise occur?

    I suggest one of two things:

    You stick to your realm of acknowledged expertise

    Hire someone who has an actual appreciation of thought in music, if not music itself

    Oh wait! This falls neatly into a long history of Euro-centric musical thought… People with "soul" have a natural primitivism (they use their sweaty bodies to make it) and they don't use machines (which take people to use their minds).

    Think I'm making too much of an offhand comment? Words have power. You're a "journal," so you should know better.


  • FCM

    I know, the button says "humanize" on it, but that's something that should be examined in itself.

    I mean, it's a really powerful idea to say that something is in-authentic and cold and "soulless" because it's made with a machine with a super-high degree of rhythmic accuracy.

    In other words, they're trying to say: this is a universal value of music. (Too rigid is bad. Small variations, good.) And then let us judge music by this assumption. Universal values that just happen to be theirs, sort of thing, etc.

    On another note, it's a very big difference for a journalist to say:

    I hated drum machines in 80 synth pop and here's an interesting article which might explain that.


    The cold regularity of drum machines is sometime humanized by XYZ, here's an article that explains that.

    This isn't just pedantic bickering over grammar. These assumptions are the groundwork for the larger directions we move in, as a culture. Shit like this is why EDM/et al isn't funded by the NEA or a major in music schools. What? Like it actually should be? Well, I'm just saying MAYBE…

    All this might not make sense to a 14yo who just wants to make some hot beats, but for the people who have dedicated their lives to this music, they deserve to be celebrated as musicians, just like any other musicians.

    But then there's this authenticity/cold/machine trope, which is bound up in feelings of black/gay/other-ness, and that's what should make people realize that what you say matters.

    This is the same reason I jumped on Nicholas Jaar. (BTW, after reading several of his statements, it's clear that he stands behind his particular assessment of 'honesty' in electronic music.)

    I understand if people think I'm too academic about this or whatever, fine. But if you really love this music, like I do, you're going to be stuck with it. And how people view this music determines whether is a hobby or something that our culture should celebrate. (great, now I've put everyone asleep…)

    Anyway, a 'scientific journal' should really know better!

  • leakeg

    “Yeah, Bees. F*** bees.”

    I lol'd.

    and I never lol.

  • synthetic

    I hope Steinberg pays the $32 and builds that into the Quantize feature in Cubase 7. 🙂 

  • synthetic

    Also, 8% swing is my new bestie. 

  • If architects followed the ideas this study is implying, buildings would be deformed and unstable. Not even Gaudi rejected geometry and mathematics in creation. Also, if most listeners (39 ???) prefer "humanized" rythms, how come 90% of pop and dance music is made on a perfect grid? Ridiculous assumptions that mislead readers by using the always bastardized "scientific" label.

  • I suspect the people producing the 90% of pop probably spend a lot of time humanizing the beats…

    And music is not architecture is not engeneering. As understanding math does not mean you area composer.

    As as you mention Gaudi. The secret is in the structured complexity. Too precise rhythms are boring because they are too simple, and interestingly we don't like the "white noise" randomisation for the same reason, not structured enough. Humans love structured and layerd complexity (call it ordered chaos if you like), that's how the univers works. That's why Gaudi is a genius.

  • Unable to read the original research, and the article in question is behind a pay-wall, but it seems like they're talking about the difference between beat-based randomization and tempo-based "feel" templates, the latter of which is a more recent development in sequencing. human drummers make split-second subconscious decisions, based on context/familiarity with a composition, to not only go ahead or behind a particular beat, but also to drag or rush the overall tempo. when creating an electronic composition, i take this into account, and from the example of my favorite human drummers, i introduce some of these "happy accidents" manually. i will map out tempo changes between and within sections of a song, or notice that a drum hit is better slightly off to emphasize another instrument. sometimes it's about thinking vertically as much as it is horizontally. a lot of dance music plays off rigidity, though. i think it is being aware of what a listener to a particular type of music expects.

  • Victor


    Nature is one of the most (if not the most) highly regarded scientific publication in most fields. They are not musicians, and probably made this reference to the 80s to make the note entertaining. BTW they probably won't answer your email. email the author directly if you're pissed off!

    The actual publication (the PloS One cited in the post) has to be regarded as what it is, that would be a scientific paper, more precisely a psychophysics paper. There is a whole field dedicated to the perception and production of rhythms by humans, mainly because it is indeed interesting to comprehend how and why humans are so good at perceiving repetitive structures (in time), and synchronizing to music. Moreover, understanding how this is actually implemented on a neural substrate is somewhat of a challenge. (Note: this has been part of my work a few years ago)

    A few points have been questioned in the comments:

    – Sample size. You must know that a set of 39 participants is actually quite a lot for such a study. At least it would not be regarded as too little for a publication, if it were, it would be rejected by the reviewers. Plus, it can be argued that the statistic reported (here a t-statistic) actually includes the sample size in their value. Hence a smaller sample makes it harder to see a significant value, so as soon as it is significant, you can be pretty sure it's there, irregardless of the sample size.

    – Methodology: As in any scientific paper, all of this is clearly stated in the *Methods* section of the paper. You have to bear in mind that all that has been reviewed by other researchers that have high standards. Actually there also more likely to be advocates of theories that oppose the author's than not.

    By the way if you want the original paper, you can simply email the first author and ask him for it. You may also discuss with him, researchers are usually quite easily reached, and asking for a unavailable paper is quite common. (i can also send it to you if you want)

    To summarize my point, one must bear in mind that this is scientific work. It is part of a bigger field, in which people dedicate their life to this topic. They are not making a point on the 80's music, but on human perception of some sort of rhythm. And thy are actually making a good point that had be previously under studied.

    Also, if you're so interested in all this, read the paper, or check out "rhythm perception" in google scholar (lots of papers are free).

    As a final remark, here is an example of robust results from this line of research. Did your know that when people tap to a beat, a simple tempo sequence for example, they tend to tap slightly before the sound comes out?

    This effect has been known as the Negative Mean Asynchrony (look it up)

  • Jengel

    Few Points of view from an "academic":

    1) The current scientific publishing paradigm sucks, sorry to everyone who can't see the nature article because they're not going to a university that pays millions for access each year (I'm looking at you nature, which has had a bunch of baby nature journals to justify charging more money). Luckily the article itself is accesible.

    2) The article points to a powerful tool, but the focus is all wrong. This conversation should not be about what types of rhythm are more "human" or "natural", or what someone thinks of the 80's. The broader point is that statistical correlation is a powerful tool to define a spectrum of micro rhythmic styles. I'm sure if you took some of your favorite drummers that you sample, and looked for correlations in their playing over different time scales (let alone correlations between other musicians in a band (ex. the bassist playing back behind the beat)) you would find a whole rainbow of interesting correlations that would define a certain rhythmic style. Now, styles come and styles go, (some people liked the 80's quanta, some people like blues, etc…), but having a better understanding for what makes things sound the way they do opens up the door for more expressive control as a digital performer (imaging having a knob that goes between Fela Kuti and Elvin Jones), and more awareness as a musician in general.

  • kconnor9000

    Electronic Musician had a fantastic article back in the late 80s/early 90s called "The Feel Factor" which was all about applying a consistent (rather than random) bias to your drum tracks. E.g. snares on or ahead of beat for snappy/nervous, snares behind for groovy to 'in the pocket'. Sounds pretty obvious that you won't get a strong feel coming off added random quantization noise, but will if there's a strong DC componnet (rushing, dragging) in that additive signal.

  • kconnor9000

    That EM issue was October 1987, if anyone has a scan.

    Obligatory reference to 'more Ringo' dial:

  • usedtobe

    I looove reading about art and music in such a formal way. Laptop musicians rarely write up a lab report! funny to note, both examples sounded awful to me. long range correlation could definitely be an interesting theme for algorithmic compositions, though, like instead of a randomly generated rhythm, a randomly generated (or analyzed!) rhythmic variation could be the seed for a large number of correlated variations on an initial theme.

  • experimentaldog

    I think that some academic limitations in studying EDM are more closely related to what program and school you're in.  There are many graduate programs now, especially in the arts, that have opened up to the notion of "practice as research".  I'm finding that there is more room than ever, at least in my program, to explore the literature and research of multiple disciplines that relate to EDM and my artistic practice.  I think what some people don't always get when reading some research papers, is that it is usually one study of many.  There are many other sources to look for when constructing the bigger picture.  These article's don't really build on the artistic qualities of "humanizing".  In other words, there is little attention to understanding it's use in artistic practice and related critical aesthetic theory.  Also, there are many arguments for and against pragmatic approaches to artistic research.  I found the comment made in Nature on this article quite funny.  It's in that 1st paragraph that the biased tone is set.  Someone was way too cranky to present this abstract.  I won't waste more time on talking about how this blurb reinforces artistic research concerns within academic journals and discourse.  I do think however, that there is too much emphasis on the notion of "humanization".  Yes this research is important, but why are so many worried about making something more or less human?  This is such a subjective aesthetic decision on the composer's part.  If it works for the piece to be fully quantized or not, so be it.  I personally think it's problematic to focus on whether or not we should worry about making things more human.  I see this too much in generative artistic research.  I'd rather focus on the artistic potential of the research and use within composing new works.  For example, why not compose using both approaches to create hybrid grooves and rhythms?  Electronic music discourse is still fresh when compared to many other areas of academic discourse.  I think the door is still wide open for exploration in electronic music, but it's our own aesthetic biases that sometimes try to close it.  

  • This topic could fill an encyclopedia…  but here's my two cents.  

    Sometimes on the grid quantization is good, sometimes stale.  Depends on ones mood. Haven't had much patience for using Live 8 groove features.  I'm sure they can work though.  

    I will say that electronic drums in general can sound sort of "wrong" when "humanized" in certain ways.  What I mean is that the electronic timbre is perhaps less forgiving than the acoustic drum.  An acoustic drummer can suck, (as they usually do in most garage band cases), and it's somewhat forgiven by the almost infinite spectral variation of the acoustic instrument .  Put the same drummer on an electronic kit, and the bad timing is so much more obvious and less forgiven.  

    Flying Lotus and Burial do sort of "wrong" rhythmic loops approach that sounds good for some reason.  Radiohead seemed to try the same on their new album.  I kinda like this sort off the grid sound, but I'm not real good at it myself.  It sounds to me like Flying Lotus captures a lot via a DJ style scratched bits approach, sampling scratched material into more intricate loops, which I think lends to a more off the grid feel with more variation and strange character, which is good too!

  • FCM

    The cold regularity of Kraftwerk's drum machines inspired a lot of soulful music, esp early hip hop. That's more than a small exception to their premise.

    Whenever people make a straw man out of some idea (or music), it's worth looking at why they've chosen that target. It often reveals much more about the sneerers than the sneerie. It tells you they've projected values onto that sort of music, and dismissing the music is a convenient way to dismiss the people associated with that music. Which is the original point, usually – to dismiss someone you don't like, using "universal values" as your high ground.

    As far as it being a joke, well….ok…

    I'm from Georgia, I could tell you a lot of racist jokes. They're just jokes, bro! 50 years ago, they would have been fine to tell from the front of the bus. But to someone with a little bit of education, they don't sit to well…

    There are about 1,000,000,000 ways to talk about and explain music. And the same number of jokes to tell.

    Using "scientific methods" to discuss elements of music does not demonstrate universal values, just scientifically observed values.

    Euro-centric cultures have been scientifically demonstrating their superiority over other cultures for centuries. In hindsight, we see how a narrowly defined experiment has certain prejudices built into it, but it's harder to do that when you're embedded inside the culture which determines the experiment.

    Did a bunch of people in that organization never take a class in comparative culture? I haven't, but I get exposed to the stuff from other channels. You think these people (at least 1 writer and 1 editor?) would be somewhat sensitive to these kinds of things.

  • FCM

    @Victor, thank you for the info. All the more unsettling.

    @experimentaldo, glad you have an open minded enviro. The more departments you come into contact with, the more perspectives you may encounter that are hardly so appreciative to say the least, though I'm not wishing that upon you or anyone else..

    The assumption that the intrinsic value for music lies in its humanizing properties,

    and that those humanizing properties lie in emotionally expressive ability,

    and that emotionally expressiveness lies artistic/interpretive variation from patterns (For rhythm: groove // For melody: blue notes, vibrato, ascending lines to heighten tension etc // For harmony: dissonant harmonies which build tension then resolve // For laptops: alternative interfaces // For timbre: complexity to emphasize dramatic narrative // etc )

    is a thicket of bullshit which will inevitable exclude important forms of music from:








    Namely, those types of music which don't conform to those standards.

  • FCM

    So to summarize:

    When I see someone pissing into the drinking reservoir, even though it's just a small piss, and even though it's a big reservoir – then yes, I will call them on it, even if it's just a joke.

  • guss

    purely subjective

  • J

    Interesting article. Has this really not been studied before? Baffling! I took a class about this sort of stuff years ago, and wrote a paper about rhythm. I found some pretty advanced research.

  • TR!AM1D

    @cooptrol Hate to get tedious with the logical fallacies, but your assertion has quite a bit of a false analogy and hasty generalization going on. Nobody can dispute the necessity of accurate mathematics in architecture, but Gaudi wouldn't have been famous if he'd been content designing square buildings! Just because one element of human nature requires order does not mean that everything does, and music is a perfect example of that. On a side note, science hasn't really bastardized anything here; take a look at the comments around you, and take it from me (a classically trained flutist and jazz saxophonist gone glitch hop and IDM producer) that for the time being, human performances really are (and have been) capable of being more profound than those that are gridlocked by the 90% of producers too lazy to add some element of humanity to their music. I'm not at all saying that electronic music is incapable of humanness– deadmau5 and BT have moved me in the same ways that Debussy does– but remember that pop music is hard on the "profit" end of the "profit vs. art" spectrum, and aimed at the masses rather than a select group of music ethicists.

  • i think it can be safely said that Ardour will do 1/f quantization noise before version 3.1 is released. possibly before version 3.0, even, if i get a spare few hours.

  • This is interesting work, but the authors seem to think that they invented the field when in fact it's been studied for decades by other researchers. I bet the paper was refereed by academics outside of musicology/theory; a specialist journal in those fields would have called BS on their non-existent lit review. For a taste of the vast body of existing work on micro-timing, check out the Jeff Bilmes' thesis (from 1993!), Charles Kiel's work on participatory discrepancies, Gerhard Widmer's computational modeling of expressive piano performance, and Ramirez and Hazan's work on expressive performance in jazz.

  • Best AI drummer I've found so far = Jamstix ftw

  • dmp

    Humanizing electronic rhythm, what a fascinating issue… I've always been interested in what made some music 'just OK' or 'killing riff', regardless the performer, be it a machine or a human been, a virtuoso or a beginner.

    I'm surprised that music softwares don't emphasize much more on groove features, like groove mapping and consistant microrhythmic variations. To me, it has nothing to do with random, it's the intention and the musical performance translated to electronic music. If computers can read scores, they don't know what the feel is about.

    There's some research going on in that field: "Musical rhythm in the age of digital reproduction", for instance. You can have a look at it on google books

  • ocp

    Here's an interesting article on a related subject: mismatch negativity.

  • I need to second (and obnoxiously re-quote) everything in Brian Tuley's second paragraph above:

    "I will say that electronic drums in general can sound sort of “wrong” when “humanized” in certain ways. What I mean is that the electronic timbre is perhaps less forgiving than the acoustic drum. An acoustic drummer can suck, (as they usually do in most garage band cases), and it’s somewhat forgiven by the almost infinite spectral variation of the acoustic instrument. Put the same drummer on an electronic kit, and the bad timing is so much more obvious and less forgiven."

    It's why I can happily listen to Nick Mason and Ringo Starr, but that type of playing doesn't translate well to electronic sounds.

  • P.S. – I'm kind of a fish out of water in this group, because I like electronic equipment, but not necessarily "electronic" as a genre… to me, electronic is just a means to an end, and all of the defensiveness in this thread strikes me as insecurity because you were too good to learn an instrument in fifth grade. So if it makes me a hateful racist nazi to say I'm not a fan of music that doesn't link me back to some kind of physical relationship between a performer and his/her tools, so be it, I'm a hateful racist nazi and the 1980s were an endurance test. Whatever.

    • Blob

      "ll of the defensiveness in this thread strikes me as insecurity because you were too good to learn an instrument in fifth grade." Spot on. See my own comment below.

  • *sigh* – I posted too quickly here, and I'm not meaning to pick a fight, I'm just stunned that there's this article about an improvement in humanization features which I would LOVE and would find REALLY USEFUL, and all I see here is pitchforks and torches about a negative comment being made about… not YOU, not your favorite musicians, but just a sound that to some people isn't satisfying, which is hardly a repressed minority! A decade is a long time, and I tolerated the fact that during my teenage years there wasn't much happening in pop music that I could be excited about or moved by. And when stuff is popular, you hear it everywhere, so it's not like you can just ignore it.

    So although I may have come off here like I'm being a jerk, my main point is, cool, I like the idea of a more intelligent humanization, and the people who would be interested in that PROBABLY WERE kind of annoyed by the 1980s. If you weren't, then the algorithm isn't for you, move on.

  • Now somebody give me a pat on the shoulder and tell me everything is going to be OK…

  • glumbin

    This post could have also been titled The Uncanny Valley For Sound.

  • FCM


    I don't know if your comments were directed at me, and even so, I don't take them too personally.

    But for the record, I'm a classical musician, and so I can lay claim to A) having a physical relationship to my instrument, and B) not being too lazy to learn an instrument. I've played in major NYC halls, many times and subbed in a major US orchestra.

    I have plenty of close-minded colleagues that would look at your electric guitar, and talk about all sorts of expressive handicaps: frets, electricity, reliance on circuitry to create timbre. I would disagree and I'm sure you would too.

    But they're projecting their values onto you and then judging you (all electric guitarists) by them.

    The point is not to invalidate opinions about what kind of music you like or not.

    The point is to question any sort of "universal value" that we adopt, and then use that to criticize the underlying value of other music.

    I'm sure there are a million comments like this on YouTube or other music forums deriding the cold drum machines, none of which I even blink at. But when someone writes something like this in a journal article, they need to back their shit up.

  • leakeg

    The next question is: are these preferences learnt, or are they genetic?

    I would guess the former, based on what we know about preferences for musical scales based on our cultural upbringing.

    Interesting to note that the volunteers here were all from a choir (not exactly a random sample).