Archive for October 2017

As a kid, I always wanted to be a mad scientist or inventor of some kind. So I taught myself just enough about chemistry and electronics to be dangerous, and I often had some sort of project or experiment underway. Around age 16 or 17, I was hard at work on my latest contraption—using my bed as a workbench since my desk was perpetually covered with junk. This project involved some soldering, a task at which I was moderately skilled. However, as I was leaning over my work, trying to steady myself by resting my elbow on the mattress, my arm slipped and I fell forward onto the bed with the soldering iron sandwiched between my forearm and the bedspread. Apart from the initial shock, the first sensation I recall experiencing was the smell of burning flesh and hair, followed by the realization that I had ruined my bedspread, and then very shortly thereafter, a good bit of pain.

Any number of lessons could be learned from such an experience—for instance, “Don’t solder in bed.” It’s also a reminder that there are any number of ways to generate dangerous levels of heat in close proximity to one’s body. Fortunately, this incident did not set me on fire. But if conditions had been just right, could this run-in with the soldering iron have reduced me to ash? This is just the sort of question pondered by those who investigate the phenomenon known as Spontaneous Human Combustion (SHC).

Up in Flames
Let’s start with some science. Spontaneous combustion, in and of itself, is a well-known phenomenon—and though perhaps surprising, it’s not in any way mysterious. The term is used when something erupts into flame without any apparent exterior cause (such as a spark). One classic example is the pile of oily rags. Some types of oil undergo a fairly rapid oxidation when exposed to air; it’s a straightforward chemical reaction that happens to produce some heat. If the heat cannot escape (by being dissipated into the air), it may eventually build up to a temperature above the flash point of the oil, at which point it will begin burning—just as it would if someone had dropped a hot coal onto the rags. A similar type of spontaneous combustion can occur in a pile of hay, due to the heat produced by bacteria that feed on the hay. Mechanics and farmers know all about these phenomena and generally take appropriate precautions to prevent heat from building up to dangerous levels.

But for centuries, stories have circulated claiming that a comparable process can set a human being on fire. What’s the source of this belief? Could it possibly be true? And if so, how does it happen?

Is It Hot in Here, Or Is It Just Me?
Picture this: you walk into a room and find the charred remains of a person, with only a few identifiable body parts left intact—a leg, perhaps, or maybe the skull. The area immediately surrounding the spot where the person breathed his or her last is also heavily charred, but the fire never spread to the rest of the room. It looks as if the person somehow caught on fire, but then burned up so rapidly that the fire was unable to spread. There being no matches or other apparent source of ignition nearby, it’s extremely easy to conclude that the origin of the fire must have been internal. Hence spontaneous human combustion.

What I’ve just described may sound unbelievable, but such scenes have been reliably documented hundreds of times in the last few centuries. (It’s also been fictionalized—for example, by Charles Dickens in Bleak House.) The question is not whether the bodies burned, it’s how they burned.

Light Me Up
Human fat—of which there’s usually an ample quantity even in thin people—does in fact make a good fuel. If heated sufficiently (and able to ooze out of the body), it could certainly burn quite well, perhaps using the person’s clothing as a wick like an inside-out candle. And plausibly, by the time all the fat in a body had burned, nothing would be left but ashes—not unlike cremation. But how would the fat get that hot in the first place? Some believers in SHC posit a heretofore-unidentified chemical reaction in the body that could produce a buildup of heat much like the one in the pile of oily rags. But so far, no direct evidence of such a reaction exists, and scientists remind us that combustion itself cannot take place inside the body anyway due to a lack of oxygen. In addition, there have been cases where the skin burned and not the internal organs, but no cases in which it was the other way around—weakening the theory that the source of the heat was internal. Other investigators have pointed out that no strange chemical reaction is necessary, that mundane sources of fire such as a cigarette, candle, or maybe even a spark from static electricity could potentially set fire to a person’s clothing and thus produce the required heat—consuming the “evidence” in the process.

Wouldn’t a person who has just caught on fire tend to notice that fact and do something about it? Advocates of the SHC theory generally claim that the heat is so intense and sudden that the victim is consumed before having the chance to do anything. Critics say that in fact a lower temperature of combustion explains the evidence better—that the bodies appear to have slowly smoldered over a number of hours, and that the smaller amount of heat kept the fire from spreading. And a person may not react if, for example, he or she was already dead—or maybe just drunk or drugged.

All that to say: the (rare and tragic) phenomenon of human combustion is not in question, but its spontaneity is. Even in the few cases where the victim survived or witnesses attested that there was no apparent external source of flame, there is no scientific need to imagine a mysterious internal source of heat—and no reason you should lose sleep worrying that you didn’t drink enough water today and therefore might suddenly burst into flames. All the same, I recommend doing your soldering on a nice solid table. —Joe Kissell

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More Information about Spontaneous Human Combustion…

For general information on spontaneous human combustion, see:

Sites debunking the myth of SHC include:

For a discussion that attempts to debunk the debunkers, see Spontaneous Combustion at Alternative Science.

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Bookstores are dangerous places for me. I invariably leave with less money—and more books than I’ll ever have time to read. But I have to support my habit: I’m basically an idea junkie. I like to learn things, absorb new ideas, and challenge my mind to form connections between concepts that don’t seem to go together. So I choose books not because I assume they’re true, but because I expect them to be interesting or thought-provoking. When I’ve finished reading a book, though, I usually have a pretty strong sense of whether or not I believe it. After reading a dozen books by Carlos Castaneda—along with quite a few criticisms of his work—I could only come to the conclusion that the stories he told may or may not be somewhat or completely true. This very uncertainty is one of the things that makes his books so interesting. I have since revised my conclusion—about which more later. But first, some background.

For years, as I browsed through second-hand books, I frequently came across Castaneda’s The Teachings of Don Juan: A Yaqui Way of Knowledge. I’d invariably pick it up, glance at it, and put it back on the shelf. Then I read Fritjof Capra’s The Tao of Physics, which had a brief quote from don Juan at the beginning, and that piqued my curiosity. Shortly thereafter, I ran across the book at a thrift shop and decided I could give it a whirl for 50 cents. Within a few pages I was hooked, and after finishing it I read all 11 of its successors. For better or worse, I was too late to be a groupie—in April, 1998, before I had finished reading all of the books, Castaneda died. Only then did I begin to realize the extent of the controversy surrounding his life and work, and the state of confusion he left behind among both fans and critics.

The Sorcerer’s Apprentice
For those unfamiliar with Castaneda and his books, here’s the short version of the story. Castaneda was studying anthropology at UCLA in the early 1960s, and during the course of his field research in Mexico, he claims to have met a Yaqui Indian named Juan Matus. Don Juan was reputed to be an expert on medicinal plants, and Castaneda hoped to use him as an informant to learn more about the use of peyote among certain groups of native Mexicans. The Teachings of Don Juan purports to be an anthropological study of the way don Juan used a variety of hallucinogenic plants as part of a system of sorcery. The research, however, was participatory rather than objective, and don Juan’s intent was apparently to treat Castaneda as an apprentice, indoctrinating him into the ways of the particular brand of sorcery he practiced.

The hallucinogenic plants turn out to be a red herring. In Castaneda’s next book, A Separate Reality, they have a more limited role, and from there on, they’re barely mentioned. The books focus on other aspects of Castaneda’s training as a sorcerer, along with several other apprentices of don Juan and his fellow sorcerer Genaro Flores. Eventually don Juan reveals that he only taught Castaneda about the plants to get his attention; most of the teachings are internal, psychological. Castaneda learns how to turn off his inner dialogue, control his dreams, perceive other people as luminous energy, and behave in a manner don Juan calls “impeccability.” A lot of time is devoted to an exercise called recapitulation, in which Castaneda recalls and relives all the events of his life. At the end of Castaneda’s fourth book, by which time he had been working with don Juan for over a decade, don Juan and don Genaro “leave the world,” which readers are supposed to understand not as death but as a deliberate crossing into another plane of existence.

Surprisingly, the story does not end there. Castaneda returns to Mexico two years later and meets up with the other apprentices of don Juan and don Genaro, some of whom we haven’t heard of yet. By the sixth book, The Eagle’s Gift, Castaneda and another apprentice, a woman nicknamed “La Gorda,” discover something shocking: during the years of their apprenticeship, don Juan had frequently made them shift into a heightened state of awareness, wherein he had taught them a variety of things that they could not remember in their normal state of awareness. There follows a long reexamination of their entire relationship with don Juan. They find that most of what they thought they knew was wrong or at least irrelevant; all the most crucial teachings had been hidden, delivered as they were in this altered state.

Castaneda’s penultimate book, Magical Passes, covers a series of movement exercises vaguely like ch’i kung, which are supposedly a key component of the knowledge don Juan revealed—even though they’re barely hinted at in any of the other books. Where Castaneda’s other books were simply reporting his own experiences, this one alone is actually written as an instruction manual.

Stalking Castaneda
From the publication of Castaneda’s first book in 1968 until today, he has been subject to harsh and relentless criticism. Entire books have been written on this subject, but I’ll give you just a sampling. First, many critics question whether such a person as don Juan ever existed. Only Castaneda and his close associates seem to have met him; there is no photograph or documentary evidence to prove he existed, or even a corpse—he conveniently “vanished.” Anthropologists point out that a number of the details Castaneda gave are inconsistent with what is known about the Yaqui Indians, native Mexican sorcery, and even the geography, flora, and fauna of the places Castaneda claims to have visited. Likewise, critics have cited other sources of suspiciously similar stories, suggesting that Castaneda “borrowed” some of his material. In addition, critics say, his stories read a bit too much like novels—real life doesn’t arrange itself that neatly for literary convenience, so at minimum he must have employed some artistic license in his descriptions. Then, of course, some worry that his discussions of hallucinogenic plants encourage the use of drugs.

Castaneda himself refused to respond to any of his critics. He was for the most part a recluse, declining to be interviewed or even photographed. His unwillingness to defend himself or offer proof of his claims was seen as an implicit admission of guilt; on the other hand, Castaneda’s own books repeatedly say that according to don Juan, a life of obscurity is absolutely essential to a sorcerer. Apologists thus counter that Castaneda was simply practicing what he preached.

He did, however, conduct seminars and workshops for a select few students. One of these students, Amy Wallace, was Castaneda’s lover (or one of them) for a number of years. Her 2003 memoir Sorcerer’s Apprentice gives an unprecedented (though clearly biased) inside look at the real Castaneda. A fascinating read, it details the life of a man who appears by turns to be a highly evolved guru and a megalomaniacal cult leader. Wallace’s bottom-line opinion: don Juan almost certainly did not exist, but Castaneda, though deeply disturbed, was a genius who believed deeply in the path he followed. This seemed to be the general consensus of those interviewed for the 2004 documentary film Carlos Castaneda—Enigma of a Sorcerer, made by another former Castaneda student, Ralph Torjan. This book and film together erased any lingering faith I may have had in the veracity of Castaneda’s writings. Unlike his students, I can’t take his ideas very seriously knowing what I do about him.

Is The Truth Out There?
What makes Castaneda’s books so compelling to many is their vivid descriptions of the world as perceived through the eyes of a sorcerer (or “man of knowledge”—in Castaneda’s usage, the term “sorcerer” does not carry any undertones of evil practices). Some of the experiences he reports are frightening, shocking, or simply off-putting, and they wouldn’t make the average person say, “Hey, this sounds like fun, I think I’ll become a sorcerer.” What they suggest, though, is that the underlying reality of the world is not at all as most people perceive it, that ordinary human awareness is, as it were, a bad habit.

Castaneda’s writings have attracted such a following for much the same reason as The Matrix or The X-Files: people want to believe that there’s more to the universe than meets the eye, that a more fantastic world lies beyond our perception. Whether Castaneda’s version of alternative reality is the right one, or even approximately correct, is the question. But whatever your opinion of Castaneda—a prophet, a fraud, or a misguided fool—his books are fascinating and thought-provoking. Even in fiction, there are kernels of truth. —Joe Kissell

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More Information about The Writings of Carlos Castaneda…

For a concise and even-handed overview of Castaneda’s work, published shortly after his death, see The Reluctant Sorcerer by Anupama Bhattacharya.

If you want to make up your own mind about Castaneda, read his books. My advice: don’t form an opinion based solely on the first book; they change significantly as they go along. Here they are:

cover art

Sorcerer’s Apprentice: My Life with Carlos Castaneda by Amy Wallace, though not the best-written book in the world, is well worth reading for its perspective on the Castaneda outside the books. For a very different (and also rather uncomplimentary) view of Carlos Castaneda, read A Magical Journey With Carlos Castaneda by Margaret Runyan Castaneda, who claimed to have been married to him for 13 years (though there is some dispute about whether she’s telling the truth too).

For more serious criticism of Castaneda, see for example Carlos Castaneda: Academic Opportunism and the Psychedelic Sixties by Jay Fikes or The Don Juan Papers: Further Castaneda Controversies by Richard Demille.

Martin Goodman wrote a novel called I Was Carlos Castaneda: The Afterlife Dialogues. It’s an interesting read, though not particularly believable as an accurate representation of Castaneda’s philosophy.

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The Mechanics' Institute Library in San Francisco

Books used to be such rare and wonderful things. I’m not talking about centuries ago, either. As recently as a couple of decades ago, when I was in school, I felt awestruck every time I visited the large public library downtown. It was amazing to me that as an ordinary citizen—a kid, no less—I could walk in and borrow nearly any book, no matter how old, famous, or important it was. Searching through endless card catalogs seemed like a mysterious black art, and I was always slightly surprised to find that a book I was looking for was actually on the shelves. Wouldn’t everyone in the city want to read this?

I’m equally amazed at the profound changes that have taken place in the last ten years or so with respect to how people think about books. On the one hand, there seems to be an increasingly common assumption that all useful knowledge exists in digital form, or is at least catalogued that way. Where once a search for information would begin at the library, now it seems that’s the last place many people look—if it isn’t on the Web, how important can it be? On the other hand, despite the ever-increasing numbers of books being published and mega-bookstores like Borders, Barnes & Noble, and Amazon.com, the meme of borrowing books from a library has lost a lot of its vigor. You can pick up any book you might want on the way home from work, or order it online with one click. For a certain segment of modern western society, going to a library for books is now seen as a sign of lower, rather than higher, class.

Be that as it may, libraries remain the primary repository of a huge portion of the world’s knowledge, ready to be uncovered by seekers of all kinds. But there are libraries…and then there are libraries.

Members Only
Public libraries funded by taxes are a relatively modern invention, dating back only to the mid-1800s in the United States. Before that time, members of the general public who wanted access to a large collection of books had to pay for it. One very common form of library required patrons to pay monthly or annual dues in exchange for access (which may or may not have included borrowing rights). When public libraries began to catch on, these membership libraries (also called subscription libraries) began to dwindle rapidly; there are now just 18 still functioning in the U.S.

One such library is the Mechanics’ Institute Library in San Francisco, of which I’m a member. The library was founded in 1854 as an educational resource for “mechanics”—that is, anyone in an engineering or technical field—providing not just books but classes, lectures, and cultural programs. By 1906, the library’s collection had reached nearly 200,000 volumes, but they were completely destroyed by the fire resulting from the great earthquake that hit the city that year. Within four years, however, a new building was erected for the library, and with a number of generous donations, it was back in business—this time, with a more general collection to appeal to a wider and less technically oriented audience. It also added a chess room, home to one of the oldest chess clubs in the country but available for use by all members. Today, the Mechanics’ Institute Library is still going strong, with an up-to-date and ever-expanding collection of books, periodicals, CDs, videotapes, and DVDs; high-speed wireless internet access; and a very popular series of cultural events. It’s one of my favorite spots to do research, write, or just get away from the noise and chaos of the city.

Putting Your Best Book Forward
Why would I pay to go to the Mechanics’ Institute Library when there is a perfectly good public library in town that’s much larger, closer to where I live, and free? That’s a bit like asking why I’d eat at a small, out of the way, expensive French restaurant when there’s a perfectly good mall food court nearby. In other words: you get what you pay for. When I go to the Mechanics’ Institute, I know that I will be walking into a clean, quiet, beautiful setting filled with great books—as well as intelligent and thoughtful people who, like me, care enough about the quality of their library experience to pay for it. Both patrons and staff take books very seriously—much more so, on average, than what I’ve seen in public libraries.

Plus, for all my facility with internet searches, there’s still something deeply satisfying about finding a piece of information buried in a book or magazine on a shelf in a library. Membership in the Mechanics’ Institute Library is not terribly expensive, but it does give me a certain sense of power and status to be able to swipe my magnetic card and gain access to rooms full of books that most members of the general public have never even heard of. That makes those discoveries of information all the more rewarding.

And there’s something else: reference librarians who are positively itching to help you find information. I always have to avert my eyes when I walk by the reference desk. If I make eye contact, I invariably get this guilt-inducing “why-aren’t-you-asking-me-where-to-find-old-periodicals” look, and I just can’t bear it.

Membership libraries are somewhat of an anachronism; strictly speaking, no one needs them anymore, because there are other (and, usually, cheaper) ways of obtaining almost any kind of information you may want. Yet the Mechanics’ Institute and the few other institutions like it are, to all accounts, thriving nonetheless. In part, I believe it’s because they don’t just offer information; the seriousness with which they treat their books and their mission imparts a sacred sense of knowledge as power. That reminder alone is worth the cost. —Joe Kissell

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More Information about Membership Libraries…

This article was featured in Carnival of the Infosciences #43.

A concise history of membership libraries can be found on the Redwood Library Web site, which also lists all the surviving membership libraries in the U.S.

For more information on the Mechanics’ Institute Library, visit their Web site; you may also want to read about it in reasons to be stoked you’re in san francisco. The library offers free weekly tours that include a photographic history of San Francisco.

Among the other membership libraries in the U.S. are The New York Society Library and The Providence Athenaeum in Rhode Island.

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During the summers when I was growing up, my bedroom had an air conditioner mounted in the window. I loved the hot nights when I got to turn it on, but only partially because it cooled the room. What I liked best was the sound, which I found to be very soothing. Years later, when I was in college, I had a classmate everyone made fun of because he couldn’t go to sleep without having a radio on next to his bed—playing static. For some reason, the sound of static on a radio seemed goofy in a way that the sound of an air conditioner did not, but they amounted to roughly the same thing: white noise, which has a well-known ability to promote sleep by masking other sounds.

Most of us have seen white noise generators or CDs of white noise that are sold as sleep aids—sometimes especially for infants. A different class of white noise generator is used for testing and calibration of pro audio equipment. But what exactly is white noise, how does it work, and why is it called “white”?

Pure Noise
If you think back to elementary-school science classes, you probably learned that white light is a combination of all the other colors of light; using a prism, we can separate it into its component colors. By analogy, “white” noise is composed of sounds of every frequency within the range of human hearing—roughly 20 to 20,000Hz (cycles per second)—with each part of the frequency spectrum equal in amplitude (volume). It’s called “noise” instead of “sound” because it is random in nature. Rather than simply generating a fixed tone at 20Hz, 21Hz, 22Hz, and so on all the way up to 20,000Hz, a white noise generator creates a constantly changing mixture of tones such that all frequencies have an equal probability of being audible at any given moment.

To human ears, white noise sounds like a hiss—sounds such as a waterfall, an aerosol can, and static are all very similar to white noise. Although all frequencies are represented, we perceive white noise as being relatively high-pitched—partly because higher octaves consist of a greater range of frequencies than lower ones (giving the higher-frequency sounds proportionally more energy), and partly because our ears are more sensitive to higher-pitched sounds.

White noise is good at masking most other kinds of sound because it effectively overloads or “numbs” our auditory systems. Just as it’s difficult to hold a conversation at a crowded restaurant, it’s difficult for your brain to identify any one sound or voice when you’re already hearing sound at every frequency. So it’s not the white noise itself that promotes sleep as much as the fact that it reduces audio clutter, drowning out other sounds that may distract you and therefore keep you awake.

The Color of Sound
If “white” noise includes sound at every frequency, you might imagine it would be possible to create other “colors” of noise by emphasizing certain ranges of frequencies over others. And you’d be right. There is such a thing as pink noise, as well as red, orange, green, blue, purple, gray, brown, and even black noise. Of these, pink noise is the most common—and the most clearly defined. Whereas white noise has equal energy at every frequency, pink noise has equal energy within each octave—in other words, the amplitude at higher frequencies is reduced to make it sound more balanced to the human ear. Pink noise is used for, among other things, calibrating speaker systems. The term “pink” signifies that it’s like white, but “tinted” or weighted toward the lower-frequency (and therefore longer-wavelength) sounds. However, not all of the so-called noise colors map onto the visible spectrum so clearly—and in any case, the color names are nothing more than a convenient metaphor to describe white noise that has been filtered in various ways.

Many of the products claiming to produce white noise are recordings or simulations of wind, waves, and other sounds that are in reality quite a bit more complex than white noise. Not that there’s anything wrong with that—the sound of rain on the roof can be very soothing and can have most of the same masking benefits as white noise. And just as the term “white noise” can be stretched somewhat in meaning to include what you might call “off-white” noise, it also can have a more metaphorical sense, as in “meaningless chatter.” But what I’d like to hear is a recording that sounds just like my old air conditioner—complete with the hum that the compressor made every time it came on. For me, that would beat a melatonin tablet washed down with a glass of warm milk. —Joe Kissell

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More Information about White Noise…

This article was featured in Encephalon #2, a neuroscience blog carnival.

General information about white and pink noise can be found at:

Also see The Colors of Noise by Joseph S. Wisniewski, which attempts to give technical definitions for all the noise “colors.”

cover art

Looking for a white noise generator or CD to help you sleep? Amazon.com has a number of machines that may fit the bill.

Or try these sources:

White Noise is the name of a movie scheduled for release in January, 2005. Visit its Web site or watch a trailer.

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When I began making audio recordings of Interesting Thing of the Day articles, I immediately realized that my office was not acoustically appropriate. There were too many extraneous sounds—fans, hard drives, and so on—and my fancy new microphone picked them all up perfectly. So I decided to set up a little recording studio for myself in a closet. The closet door nicely blocked out the sounds of the room, as well as most of the sounds from other parts of the house, traffic outside, and so on. The problem was that the recordings sounded like I was in a closet, or maybe a bathroom—the flat walls and ceiling added an unpleasant reverberation to my voice. In professional recording studios, the walls are usually covered with special acoustic foam to absorb most of those reflected sounds and give the sounds being recorded a more pristine character. I didn’t have any acoustic foam handy, so I covered the walls with old blankets instead. That did the trick: now my voice sounds correct, and I can always add reverberation or other effects later if I feel the need.

Recording studios are generally designed both to keep outside sounds from being heard inside the room and to keep sounds generated inside the room from bouncing around enough to be picked up by the microphones—and they invariably do a better job at both than my makeshift studio-in-a-closet. However, they’re still far from soundproof or acoustically “dead.” A noisy motorcycle or heavy truck coming down the road outside might still be heard inside, and the surfaces inside the room still reflect a bit of sound.

Is There an Echo in Here?
If you’re recording a CD, these minor imperfections in the room’s acoustic quality are no big deal. But if you’re trying to perform delicate, highly accurate measurements of the dynamic response of a microphone or the frequency range of a speaker, any reflections or unintended sounds at all can invalidate your tests. So you need a heavier-duty soundproof environment than a recording studio: you need an anechoic chamber.

The word “anechoic” means, as you might guess, “without echoes.” Naturally, an ordinary room is going to reflect sound less than a canyon or a concert hall, but making a room completely immune to sound reflections is surprisingly difficult. The first step is to consider the angles of the surfaces in a room. Flat, hard surfaces reflect sound best, and when you have more than one such surface—especially when they’re parallel—you’re guaranteed to have some sort of echo. Then you have to consider the composition of the walls, floor, and ceiling. A given material (think of the blankets lining my closet walls) may absorb certain frequencies of sound effectively, while reflecting higher or lower frequencies. In addition, sound volume comes into play: materials that absorb relatively quiet sounds may nevertheless partially reflect louder sounds.

So most anechoic chambers have all their interior surfaces lined with thick wedges of fiberglass (or in some cases polyurethane) foam. The wedge shape traps sound waves by reflecting them onto another part of the wedge rather than back into the room. The foam itself then absorbs the vibrations (turning them into heat). The deeper the wedges are, the lower the frequencies of sound that can be absorbed. To absorb all sounds within the range of human hearing requires immense wedges, shrinking the interior space of the room and adding to its cost. Meanwhile, it’s equally important to prevent sounds from the outside from entering the room. The walls themselves (behind the foam wedges) must be quite dense and thick; in addition, anechoic chambers are generally isolated from the rest of the building by “floating” them on a set of large springs.

The Cone of Silence
I’ve never been inside an anechoic chamber myself, but my friend Darren has. Darren is a record producer, and he uses his considerable audio engineering talent to turn my raw voice recordings into the polished programs heard every day by our audio subscribers. He once visited an anechoic chamber used for testing microphones at the Peavey Electronics headquarters in Meridian, Mississippi. Darren described the experience as being just like walking into Cerebro, the psychic amplifier created by Professor Xavier in the X-Men comics and movies. Because the floor, ceiling, and even the door of an anechoic chamber must be kept as free as possible of reflective surfaces, the working area is a small stage suspended in the very center of the room, accessed by a long walkway. The walkway and stage included handrails because people inside the chamber frequently become disoriented. Although we are not normally conscious of it, the tiny reverberations from sounds hitting the walls, floor, and ceiling of ordinary rooms are picked up by the inner ear and used to enhance our sense of balance. Without these cues, it’s harder to know which way is up.

Darren described the experience of utter silence in the room as being very strange. Because there was no ambient noise at all, the smallest sounds—a whisper, the sound of breathing, or even a shoelace flapping—seemed astonishingly loud. But the important thing for the technicians testing audio equipment in the chamber is that if they’re measuring the sensitivity of a microphone or the output of a speaker, they can be certain that only the sounds they deliberately generate inside the room have an effect on their test equipment.

Other Other Echoes Echoes
Although anechoic chambers were originally designed as places free of sound echoes, the term “anechoic chamber” is also used to describe a type of room specially designed and shielded to prevent the reflection of radio waves and other electromagnetic radiation. Manufacturers use such chambers for testing antennas, radar equipment, and other electronic devices that produce radio waves, to ensure that their measurements do not include any reflected signals. The materials and designs used to prevent the reflection of radio waves are different from those used in conventional anechoic chambers, but the basic principle is the same: absorb, don’t reflect. Interestingly, though, some anechoic chambers designed for electronics actually have surfaces that reflect sound quite well.

Being a city dweller, I’m accustomed to a certain amount of background noise 24 hours a day. At the same time, I can do without the more obnoxious sounds of traffic, loud music, shouting, sirens, and so on. Even though the absolute silence of an anechoic chamber sounds delightful for a meditative retreat, I imagine the novelty would rapidly wear off. If the sound of my own breathing became distracting, I may be on my way to a padded room of another kind. —Joe Kissell

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More Information about Anechoic Chambers…

Read Anechoic chamber in the Wikipedia for a brief overview of anechoic chambers.

For more information on audio anechoic chambers, see:

For more information on EMF anechoic chambers, see:

When I created my recording-studio-in-a-closet, I encountered another problem: how to control the software on my computer, which was outside the closet (so the microphone would not pick up its noise). I solved this by using my Bluetooth-enabled cell phone as a remote control, thanks to a piece of software called Salling Clicker. You can read more about my experience in Salling Clicker in Action, an article I wrote for TidBITS.

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