The sound of the whistle

In his absolutely terrifying 1904 short story "Oh, Whistle and I'll Come For You, My Lad," British writer M. R. James tells us about a young professor named Parkins who is recovering from an emotional upset and decides to take a seaside R&R in coastal Suffolk.

Parkins is wandering the beach one day, and finds, half-buried in the sand, an ancient bronze whistle.  A historian himself, he is intrigued, and cleans it up, discovering upon inspection that it has two inscriptions, both in Latin: "Quis Est Iste Qui Venit?" ("Who is this who is coming?") and the more mysterious "Fur Fla/Fle Bis," which Parkins is unable to disentangle, but which James intended us to piece together as "Fūr: flābis, flēbis," which roughly translates to "Thief: if you shall blow, you shall weep."

Parkins, as it turns out, should have worked harder to figure out the second inscription.

Evidently not realizing that he is in a horror story, he blows the whistle, which is unexpectedly loud and shrill.  Nothing happens -- at least immediately.  But later that day, while out on the beach, he sees in the distance an "indistinct personage" who seems to be attempting to catch up with him, but never does.  The person moves in a strange way -- a kind of flapping, flailing motion, not at all like a human running.

Then he starts hearing noises at night, which at first he attributes to mice.  A bellhop has a panic attack while looking up at Parkins's room from the outside, saying that there was a "horrible face" in the window.  One of the maids complains that Parkins didn't have to pull all the bedclothes off the bed and throw them onto the floor in the morning -- when he'd done no such thing.

What the whistle had summoned was an incorporeal creature who fashions itself a body out of whatever happens to be handy -- in the case of the bellhop, for example, a twist of fabric from the curtains.  At the end of the story, as Parkins is lying in bed, sleepless, the light of the Moon coming in through the window, he sees the sheets and blankets on the other bed suddenly pull together into a crumpled humanoid form, and sit up -- then it reaches out its cloth arms, feeling around to try and find him.

It is one of the most flat-out terrifying scenes I've ever read.

I was put in mind of James's story (rather reluctantly) by a paper in the journal Nature Communications Psychology about a fascinating study of what are called "Aztec death whistles" -- ceramic whistles shaped like skulls, that when blown generate an unearthly sound that resembles a high-pitched human scream.

The study looked at human responses to the sounds, and found that one hundred percent of volunteers had "strongly aversive reactions," which is science-speak for "the test subjects nearly pissed their pants."  The researchers did fMRI scans of volunteers' brains, which showed strong responses in the auditory cortex and amygdala (the latter being central to the fear response).  The authors write:

All four skull whistle sound categories were rated similarly in terms of their high negative valence, and they revealed significantly the most negative valence compared with all other sound categories.  Skull whistles trigger significantly higher urgent tendencies than all other sound categories...  Skull whistles sounded more unnatural than original biological sounds (human, animal, nature) and exterior sounds, and they largely also sounded less natural than some musical sounds (music, instrument)...  The sound of skull whistles thus seems to carry a negative emotional meaning of relevant arousal intensity.  This seems to trigger urgent response tendencies in listeners, which is a typical psychoacoustic and affective profile of aversive, scary, and startling sounds.

The authors admit they have no idea what the whistles were used for, but suggest that they might have been played during human sacrifices.

Because those apparently weren't horrifying enough already.

Anyhow, naturally I wanted to hear these things for myself, so I clicked on the link that has clips of the whistles being blown.

I'd read the paper, so I should have been ready for it, but holy shit, those things are scary-sounding.  The hairs on the back of my neck stood up.  I'm really sound-sensitive, so maybe I had a stronger reaction than you will; but it bears mention that when I listened to the clips, my dog Rosie was asleep on the papasan chair in my office, and she freaked.  Normally Rosie is the most placid of animals; she's very used to my having music going on my computer, as well as hearing voices and other sounds from things like YouTube videos, and ordinarily has zero reaction to any of it.  But when this thing sounded -- and I didn't even have the volume up very high -- she jolted awake, eyes wide, hackles raised, and looked terrified.

So whatever it is that these Aztec death whistles are doing to the brain, I can say with some confidence that dogs also have the same response (at least to judge by a sample size of one).

However, I'm happy to report that thus far, playing the whistle noises hasn't generated any other untoward effects.  I haven't seen any horrible faces in my office window, and I've yet to be chased around my house by an animated bedsheet.  So that's good.  But I don't think I'm going to listen to those whistle clips again.

Suffice it to say that, like M. R. James's character Parkins, I'm not eager to repeat the experience.

****************************************

Pitch perfect

It's funny, sometimes, what we don't know.  I've played the flute for almost forty years -- started out self-taught (bad experience with elementary school band), then was lucky enough to study with a brilliant classical flutist named Margaret Vitus for five years when I lived in Seattle.  I've since played in three different bands and a community orchestra, and besides the classical repertoire, I've become fairly proficient in Celtic, English country dance, and Balkan music.

But it wasn't until the last band I was in, the trio Crooked Sixpence, that I actually figured out some peculiarities of my own instrument.  I was fortunate enough to play with Kathy Selby, who is not only a brilliant Celtic fiddler but a physicist (then teaching at Cornell University).  Kathy taught a class called "The Physics of Music," which combined her two areas of expertise -- and the class looked at, amongst other things, how specific instruments work.

So it seemed natural for me to ask her something that's always puzzled me; why flutes go sharp once they warm up.  The difference is greater (obviously) when it's cold out -- so the temperature increase the instrument experiences once I start playing it is bigger -- but it is noticeable even on a warm day.  On first glance, it seemed to make no sense.  Objects expand when they warm up, so (I thought) the thermal expansion would make the tube longer, and the pitch should drop, making it go flat.  That they actually go sharp seemed completely opposite to my intuition.

And of course, she immediately knew the answer; it's because sound travels faster in warm air.  Since the frequency of a wave is directly proportional to its velocity, if the sound wave is moving faster, its frequency goes up -- and so does its pitch.  The thermal expansion of the tube is minuscule, so any drop in pitch from the tube becoming longer is negligible.

I also found out from Kathy -- when I attended a free lecture on musical acoustics she gave -- why a bunch of different instruments playing the same note all sound different.  I knew that that the fundamental note (let's say it's A above middle C) has to have a wavelength that is the same length as the tube (or string, or whatever) of the instrument that's playing it.  A sound of that wavelength will set up a standing wave that then sets the air moving and projects outward toward the listener.

But a flute playing an A above middle C and a fiddle playing an A above middle C sound completely different.  The reason, I learned, is because there is more than one wavelength that fits a particular length:

[Image is licensed under the Creative Commons Allowed and forbidden standing waves, File:High School Chemistry.pdf, CK-12 Foundation]

The ones on the left "fit;" the ones on the right don't.  The top one on the left is the fundamental pitch.  The ones further down are called overtones, and that's the key to why instruments sound different.  The greater the number and amplitude of the overtones, the more the sound wave the instrument produces deviates from a simple sine curve.

Sound waveforms, top to bottom -- flute, piano, trumpet.  [Image from Doug Davis, 2002]

As you can see, flute tones are pretty simple, very close to a sine curve.  But look at the trumpet waveform.  Same fundamental pitch -- the peaks and troughs of the waveform line up with the flute's and the piano's -- but the shape is entirely different.  That's because of the number, and intensity, of the overtones.  (Instruments that have forced vibrations from a bow being dragged against the string, like violins and cellos, have a lot more overtones -- and thus more complex waveforms -- than instruments where a string is plucked or struck, like guitars and pianos.  The same comparison holds for double-reed wind instruments like oboes and bassoons, which produce way more complex sound waveforms than flutes do.)

The whole topic comes up because of a paper that was presented recently at the annual meeting of the American Physical Society, which contained the solution to a long-standing question in the physics of music; why do the pipes of an organ play a tone that is considerably lower pitched than the sound wave that should fit the length of the pipe?

Organ builders have known about this for over a hundred years; to get an organ pipe to sound the note you intend, you have to build it a little shorter than you'd expect.  (The "end correction" you have to use to make the pipe's pitch match what physics would predict from its length is equal to 0.6 times the radius of the pipe.)  But why?  Shouldn't a wave of that length be a little too long for the pipe, and be one of the "forbidden standing waves" shown on the right side of the first figure?

The key to the answer was discovered, quite by accident, by a Swiss organ builder named Bernhardt Edskes.  He was working on repairing an organ, and noticed that a tiny piece of gold plating had flaked off one of the pipes.  He only saw it because when he played that pipe, the flake floated above the top of the pipe.  But since there was air blowing up the pipe, why wasn't the flake completely blown away?

Leo van Hemmen, a physicist at the Technological University of Munich, realized that both the "end correction" question and Edskes's mysterious floating piece of gold were the result of the same phenomenon.  When an organ pipe is played, the rising column of air causes the formation of a stable vortex above the top of the pipe.  When van Hemmen used smoke to make the vortex visible, and its height turned out to be exactly 0.6 times the radius of the pipe, he knew he'd solved the puzzle.  The spinning cylinder of air creates a longer tube for the sound to resonate in -- so the wavelength of the lower-pitched note fits perfectly.

Humans have been making music for tens of thousands of years, and I find it fascinating that we are only now understanding the intricacies of what's going on inside the instruments we play.  It may be that we don't need to know the physics of music to enjoy it, but for me, it's fun to find out how complex these things are -- and that all As above middle C are not created equal.

**************************************

Acoustic illusions

Some years ago I was in a musical trio called Alizé that specialized in traditional French folk music.  One weekend we played a gig at a local music festival, and we were approached by a very nice fellow named Will Russell who told us how much he'd enjoyed our playing -- and said he thought we should record an album.

Will is no amateur music enthusiast.  He runs Electric Wilburland, a recording studio in Newfield, New York, not far from where I live.  Will is a Grammy-winning sound engineer, and as we soon found out, is truly gifted at making musicians sound their absolute best.  He also has some nifty tricks up his sleeve, which we discovered when we were working on the audiofile for a four-tune medley we'd just recorded.

"What's your concept for this one?" Will asked.

We explained to him that the first tune is solemn, almost religious-sounding, and it gradually ramps up until reaching a peak in the last tune, a lightning-fast dance tune called "Gavotte des Montagnes."

"So we start out in church," our guitarist explained, "then there's the recessional... then there's the party."

Will frowned thoughtfully.  "Okay, for the first bit, in church.  Do you know what church you want it to be in?"

I thought he was joking.

"No, really," he explained.  "I have acoustic sampling from a bunch of different cathedrals.  Do you want to sound like you're in St. Paul's?  Or York Minster?  Or Chartres Cathedral?  Or...?"

"No way," I said.

He proceeded to play our track to us, applying the acoustics of various different cathedrals.  We ended up picking Chartres, not only because it sounded awesome, but because it seemed appropriate for a French song.

[Image licensed under the Creative Commons Marianne Casamance, Chartres - Cathédrale 16, CC BY-SA 3.0]

With all due modesty -- and with many thanks both to Will and to my bandmates -- the album (titled Le Canard Perdu) came out sounding pretty cool, and if you're so inclined, it's available on iTunes.

The topic comes up because of a paper this week in Science Advances by a team led by Theodor Becker of ETH Zürich, which has looked at the question of how we know what kind of space we're in acoustically, and then seeing if there's a way to mimic that by altering the qualities of the sound -- characteristics like reverb, interference patterns between whatever's producing the sound and the various echoes from surfaces, and so on.  The ultimate goal is to achieve whatever kind of acoustic illusion you want, from being in a particular cathedral to being underwater to having the echoes (or even the original sounds) cloaked entirely.

I don't pretend to understand the technical bits; but the results are mind-boggling.  The authors write:

[W]e demonstrate in 2D acoustic experiments that a physical scattering object can be replaced with a virtual homogeneous background medium in real time, thereby hiding the object from broadband acoustic waves (cloaking).  In a second set of experiments, we replace part of a physical homogeneous medium by a virtual scattering object, thereby creating an acoustic illusion of an object that is not physically present (holography).  Because of the broadband nature of the control loop and in contrast to other cloaking approaches, this requires neither a priori knowledge of the primary energy source nor of the scattered wavefields, and the approach holds even for primary sources, whose locations change over time.

The military applications of this technology are apparent; cloaking the sound of a surveillance device (or other piece of equipment), or creating the illusion that it's something (or somewhere) else, are of obvious utility in military settings.  As a musician, I'm more interested in the creative aspects.  The ability to create what amount to acoustic illusions is a significant step up from Will's already-impressive magic trick of teleporting us to Chartres Cathedral.

The purists in the studio audience are probably bouncing up and down in their chairs with indignation at the idea of further mechanizing the process of making (and recording) music.  I've heard plenty of musicians decrying the use of features like auto-tune -- the usual objection being that it allows second-rate singers to tune up electronically and sound way better than they actually are.

No doubt it's sometimes used that way, but I'll throw out there that like any technology for enhancing the creative process, it can be used as a cheat or it can be used to further expand the artistry and impact of the performance.  One example that immediately comes to mind is the wild, twisty use of auto-tune in Imagine Dragons' brilliantly surreal song "Thunder:"

But for innovative use of technology in music, there's no one better than the amazing British singer Imogen Heap.  Check out her use of looping for this mind-boggling --and live -- performance of her song "Just for Now:"

I've been a musician for forty years and have been up on stage more times than I can even begin to estimate, and I can't imagine having the kind of coordination to pull off something like that in front of a live audience.

So I find the Becker et al. paper exciting from a number of standpoints.  When you think about it, musicians have been experimenting with new technology all along, and not just with electronic tinkering.  Every time a new musical instrument is invented -- regardless if it's a viola da gamba or a theremin -- it expands what kind of auditory experience the listener can have.  When electronic music first gained momentum in the 1960s with pioneers like Wendy Carlos and Isao Tomita, it elicited a lot of tut-tutting from the classical music purists of the day -- but now just about everyone recognizes them for their innovative genius.  Masterpieces like Carlos's Switched-On Bach and The Well-Tempered Synthesizer and Tomita's Firebird and The Snowflakes are Dancing have rightly taken their place amongst the truly great recordings of non-standard performances of classical music.

I'll be interested to see where all this leads.  I'll end with a quote from Nobel-Prize-winning biochemist Albert Szent-Györgyi.  He was speaking about science, but it could apply equally well to any creative endeavor.  "Discovery consists of seeing what everyone has seen, and thinking what nobody else has thought."

 **************************************

London in the nineteenth century was a seriously disgusting place to live, especially for the lower classes.  Sewage was dumped into gutters along the street; it then ran down into the ground -- the same ground from which residents pumped their drinking water.  The smell can only be imagined, but the prevalence of infectious water-borne diseases is a matter of record.

In 1854 there was a horrible epidemic of cholera hit central London, ultimately killing over six hundred people.  Because the most obvious unsanitary thing about the place was the smell, the leading thinkers of the time thought that cholera came from bad air -- the "miasmal model" of contagion.  But a doctor named John Snow thought it was water-borne, and through his tireless work, he was able to trace the entire epidemic to one hand-pumped well.  Finally, after weeks and months of argument, the city planners agreed to remove the handle of the well, and the epidemic ended only a few days afterward.

The work of John Snow led to a complete change in attitude toward sanitation, sewers, and safe drinking water, and in only a few years completely changed the face of the city of London.  Snow, and the epidemic he halted, are the subject of the fantastic book The Ghost Map: The Story of London's Most Terrifying Epidemic -- and How It Changed Cities, Science, and the Modern World, by science historian Steven Johnson.  The detective work Snow undertook, and his tireless efforts to save the London poor from a horrible disease, make for fascinating reading, and shine a vivid light on what cities were like back when life for all but the wealthy was "solitary, poor, nasty, brutish, and short" (to swipe Edmund Burke's trenchant turn of phrase).

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

The music of the spheres

It probably sounds uncharitable of me, but I wish that all of the people who can't be bothered to exert the time and effort to learn a little bit of science would stop pretending that they know what they're talking about.

We saw it last week with Ken Ham, blathering on for two hours about "historical science" while Bill Nye stood there staring at him with a "what the fuck are you talking about, dude?" expression that has got to become the basis of a meme somehow.

Of course, it's not just the creationists who babble about scientific concepts like the Second Law of Thermodynamics as if they actually understood them.  The New Age types do the same thing, usually venturing off instead into such esoteric fields as quantum mechanics, evidently mistaking "I don't understand quantum physics" as being the same as "quantum physics means whatever I decide it means."

I ran into an especially good example of this a couple of days ago, over at the loony website Spirit Science and Metaphysics.  And one of their posts, "Here's Why You Should Convert Your Music to 432 Hz," should probably be up for some kind of woo-woo wingnut award.

If there is such a thing.  Which there should be.

In this article, we find out that we are jeopardizing our health, all because we've been tuning our musical instruments wrong:

Most music worldwide has been tuned to A=440 Hz since the International Standards Organization (ISO) promoted it in 1953. However, studies regarding the vibratory nature of the universe indicate that this pitch is disharmonious with the natural resonance of nature and may generate negative effects on human behaviour and consciousness. Certain theories even suggest that the nazi [sic] regime has been in favor of adopting this pitch as standard after conducting scientific researches to determine which range of frequencies best induce fear and aggression. Whether or not the conspiracy is factual, interesting studies and observations have pointed towards the benefits of tuning music to A=432 Hz instead.

432 Hz is said to be mathematically consistent with the patterns of the universe. Studies reveal that 432 hz tuning vibrates with the universe’s golden mean PHI and unifies the properties of light, time, space, matter, gravity and magnetism with biology, the DNA code and consciousness. When our atoms and DNA start to resonate in harmony with the spiraling pattern of nature, our sense of connection to nature is said to be magnified. The number 432 is also reflected in ratios of the Sun, Earth, and the moon as well as the precession of the equinoxes, the Great Pyramid of Egypt, Stonehenge, the Sri Yantra among many other sacred sites.

Count 'em up, folks.  We have:

• vibrational frequency
• resonance
• Nazis
• the "Golden Mean"
• the pyramids
• conspiracies
• a "grand unified theory"
• DNA
• spirals
• Stonehenge
• some vague shit about astronomy
• "sacred sites"
• light, time, space, matter, gravity, and magnetism

That's it, folks.  I think we can pack it in; we have reached Bullshit Nirvana, here.

Oh, yeah, and it wouldn't be complete without a quote from Nikola Tesla:

“If you want to find the secrets of the universe, think in terms of energy, frequency and vibration.” – Nikola Tesla

Presupposing, of course, that you have taken a physics course and understand what anything that Nikola Tesla said actually means.

We're then shown a bunch of photographs that are supposed to be relevant, including ones that look like this:

[image courtesy of the Wikimedia Commons]

These images are the patterns that emerge from standing waves in a metal plate (either free or forced vibrations); there's nothing mysterious about them.  (Although the theory behind the patterns is wildly complex.  I have a bachelor's degree in physics, and the math is way beyond anything I am capable of comprehending.)  Once you know what the images are, it's hardly a surprise that using a different frequency (432 Hertz rather than 440) will produce a different pattern.  But what they're telling us boils down to the 432 Hertz pattern somehow being "prettier..." which translates, apparently, to its having beneficial health effects.

Or something.  It's kind of hard to tell, frankly, what they do mean.  If you thought the preceding quoted paragraphs were bad, take a gander at this one:

All of the frequencies in the spectrum are related in octaves, from gamma rays to subharmonics. These colors and notes are also related to our Chakras and other important energy centers. If we are to understand that (…) Chakras are connected to the Seven Rays of the Solar Spectrum, then the notes and frequencies we use for the same should be the same. A432 Hz is the tuning of the Cosmic Keyboard or Cosmic Pitchfork, as opposed to the A440 Hz modern ‘standard.’ It places C# at 136.10 Hz ‘Om,’ which is the main note of the Sitar in classical Indian music and the pitch of the chants of the Tibetan monks, who tell us ‘It comes from nature.’

Oh.  The "Cosmic Pitchfork."  That makes total sense.  And I'm sure that the Tibetan monks are perfectly nice people, but the fact is, I wouldn't go to them for instruction on physics, any more than I'd go to Stephen Hawking to receive the teachings of the Buddha.  And talking about "octaves of gamma rays" makes about as much sense as talking about "photons of musical pitch."

But that doesn't matter.  You must immediately retune your guitar and fiddle and other musical instruments, because otherwise your pitch will clash with the Cosmic Keyboard.  And heaven knows we wouldn't want that to happen.

What bothers me about all of this is not that some woo-woo has a weird idea; having weird ideas is kind of the woo-woo raison d'être, after all.  What bothers me is that because the writer of this article is able to throw around some fancy-sounding scientific jargon, coupled with jargon from New Age metaphysics, there is this veneer of sensibility to it -- if you don't know a lot of science yourself, you might be fooled into thinking that what is on this webpage actually says something.  And a lot of people apparently have been fooled.  All you have to do is do a Google search for "432 Hertz tuning" and you will find, literally, hundreds of sites like this one that claim that if you don't retune your music, you are risking remaining unenlightened forever.

I have known more than one person who has regularly been suckered by this kind of stuff.  One of them, a long-ago acquaintance in Seattle who seemed to fall for every piece of freshly-minted New Age nonsense that came down the pike, would have panicked upon reading this, and not only would have immediately paid to have her piano retuned, but she would have done whatever she could to make sure that her CD player was outputting sounds tuned to a scale based on A = 432 Hertz, not the standard 440.  (And she would have attributed every joint pain, headache, and queasy stomach she'd had in the past three years to listening to music at the wrong pitch.)

So just to be clear; there is no health (or emotional, or spiritual) benefit from tuning to 432 Hertz.  It's even been the subject of an experiment, by Trevor Cox, professor of acoustical engineering at the University of Salford, a study that (surprise!) blew down the claim completely.  Put simply, this contention is 100% pure, grade-A, unadulterated pseudoscientific garbage.

And I think to round things out, I'm going to listen to one of my all-time favorite pieces of music -- Domenico Scarlatti's sparkling Sonata in D Major, K. 96, "La Chasse" -- as played by the brilliant Stephen Malinowski (and accompanied by a cool graphic of the musical score).

On a harpsichord tuned to A = 440 Hertz.  Take that, woo-woos.  And tell me if, after listening to this, you felt "aggressive and disharmonious."  Because if so, I think there's something more wrong with you than the way your music is tuned.