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Focusing Audio 171

Alien54 writes: "The fine folks at the MIT Sound Media Lab have come up with a cheap and practical way to focus sound: "A beam of light can be controlled in many ways - it can be aimed at one person in a crowd, spread to fill a room, or projected to create rich, distant imagery. We can now do these very same things with sound. The Audio Spotlight can be used in two major ways: As directed audio, sound is directed at a specific listener or area, to provide a private or area specific listening space. As projected audio, sound is projected against a distant object, creating an audio image. This audio image is literally a projected loudspeaker - sound appears to come directly from the projection, just like light." While still under development, they are testing applications of the device in collaboration with several of their media lab sponsors in preparation for eventual commercial release."
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Focusing Audio

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  • by nhm ( 39489 ) on Sunday August 27, 2000 @09:58AM (#824334) Homepage
    All very interesting, but the information seems to suggest a bottom-end frequency response of a few hunred Hz. The figures, at least, seem to stop at 400Hz.

    Now... 400Hz is quite high really. For the musically inclined, concert A is 440Hz. Off the top of my head that's significantly higher than the fundamental frequencies involved in, say, male speech. Until they can get that extended down to somewhere closer to 150Hz (remember - this is logarithmic so one octave is a doubling / halving of frequency) I would think there will be difficulties in using it.


    PS - Did anyone count the number of `TM's around the place!!
  • SpotSpeaker?? Or AudioSpot???

    Maybe I should register audiospot.com now.
  • Dude, you sound like your stoned or something.
  • Invasion of privacy? Get real, you are in a public place that is owned by another person/business, you have no privacy.

    If they want to film you shopping to help them with product placements to maximise sales and profits, that is their right to do so.

    Grow your own food in your backyard if you want privacy about what food you eat.
  • >first, the stockholders of supermarkets aren't >necessarily "bourgeoisie". You can be A >stockholder, too; just buy some stock. And it's >possible for a supermarket chain to be entirely >owned by individual small investors like you. >And the chain would still practice sleazy >marketing practices; so, I don't see how there >is a class war at work here.

    Okay, we're really going off topic here, but c'est la vie :)

    Well, IANAM (I-am-not-a-marxist), but from what I know from studying their thought some, they would explain this as a cornerstone of the 'class war', since the reason that individual small investors buy stock, is so that they can get a monetary return on their investment, so that they can be richer; eventually joining the 'Bourgeoisie' if they are fortunate and or shrewd.

  • You've obviously never been to goatsex.

    (also, most amusement parks have stagnanted (ooh, a ride!); see the begining of 'house on haunted hill' for some of the new shit they're doing)

  • Never heard about the clockwise thing, and now that I think about it the larger supermarkets I frequent have entries in the left side of the store, so you move clockwise. The produce is near the entrance, and the frozen food is on the far right end. The "impulse" buys are near the counter of course, but now that I think even further about it I almost never buy anything from them. I wouldn't read too much into marketing research; they come up with some pretty wacky stuff.

    And slashdot has reduced me to writing about where the produce in my local supermarket is. Please, someone moderate me down as off-topic. I need it.
  • The precision we could have surround sound with this?

    Six speakers? Phhhhpt! I have a sound laser creating speakers wherever they're needed out of my specially treated walls!

    Perhaps A wall with tiles that can vibrate/move independently from one another?

  • That's incredibly unlikely. Firstly you have to have almost no will whatsoever to actually have this affect you in any way. Also you have to understand that even for the human subconciousness connect to the waking mind requires a great deal of personal training and the like (I've looked into it).
    The internet has breed a great deal of loonies who have found a bunch of other loonies who have absolutely no education in matters of science and the like and who don't have a very firm grasp on the validity of various theories. Logic contradicts a system that cannot be proven and there are a great many assumptions that are in this. Firstly the sound wave would have to be in a subvocal level which prevents you from actually perceiving it. Secondly when it's down that low you have to rely on a really sucker like Homer Jay Simpson to actually fall for it. Remember the studies back a number of years ago about putting subliminal messaging into advertising in the movies? Ever wonder why it dosn't seem to work absolutely (last time I checked I went to a movie there was a very obvious and very non-subliminal series of messages that I *could* see that were offering various drinks/candy/popcorn that blows that little idea out of the water really quick).
    Many people like to think that you can simply train people like Pavlov's dog and you just cannot. Human will would have to be about as low as a mental patient locked up for 20 years to get this to work.
    Even then it would only manifest itself as a possible desire and not as something that could easily be grasped in any traditional command and control sense. You would weed it out and then use your higher sense of logic to get what you needed. The American consumer is one of the most informed in the world when it comes to getting the most for the buck. Magazines like Consumer Reports and the like insure this.
  • According to the description of the device they use ultrasound in the millimeter wavelengths, this is in the hundreds of kilohertz. So your dog will not go insane, fido can't hear over 35kHz. These high frequencies are also attenuated rather rapidly in air.

    The coupling of these frequencies from the air to your body is also extremely poor. Compare this to a medical ultrasound that uses very high levels and is in direct contact with your body with gel to improve the impedance match.

    This definitely requires further study, but I wouldn't be too concerned about safety.

  • Audio Image (TM). That's nothing. If MIT had their way, they'd also own Computer Science (TM) and Linguistics (TM). It must drive the Media Lab (TM) nuts that they didn't invent the world wide web.
  • Yeah, he wants some of this:
    |\ / * \
    | X < (O===8
    |/ \______/

    http://vagina.rotten.com/fish/ [rotten.com]

  • You think drugs make the people more powerful? Forget it. Even the painkiller my dentist gave me removed from me about 1/4 of my self-control.

    Mastery of self is power, not abuse of self.
  • I am a virtual prisoner in a virtual democracy, a hostage trapped in a land that has strayed far from reality. This is my statement and a small part of my story.

    An American whistleblower and an advocate for the human rights of all, I have never used or advocated violence, nor has any state or nation ever charged me with a crime. Nevertheless, because of what I believe, say, and write, what I know and have tried to communicate, I have seen nearly six thousand days of surveillance, defamation, persecution, terrorism, mental torture, and more, for which society denies recourse and law provides no remedy.

    In 1984 and 1985, I blew the whistle on civil liberties violations involving persons at my workplace and corrupt police, prosecutors, and intelligence agents. The gangsters, government and "private," whose crimes I had tried to reveal invaded my privacy, slanderously attacked my character and reputation, impugned my sanity, assaulted me with radiation and bio-chemical weapons, killed my dog, and tortured me with electromagnetic weapons. They forced me out of my job without due process, wrecked my car, broke up my marriage, drove me into exile, violated my rights abroad, and thrice conspired to coerce my return to this benighted nation. Thrust from prosperity to poverty, from health to disability, from dignity to disgrace, I am left alone in the company of hard, sad, frightening truth. Yes, this happens here in the birthplace of modern democracy. Behind an angelic facade lurks a satanic reality, an America that pursues its critics with a fanaticism unsurpassed by any Iranian mullah, mobilizing the community in such harassment of targeted persons as the Chinese experienced in their Cultural Revolution, aping the defunct Soviet Union in its use of psychiatric evaluations as instruments of intimidation and discreditation, circumventing due process with a disregard of Constitutional liberty and human dignity frighteningly reminiscent of Germany's Third Reich.

    Many have warned that the marriage of fascist mentality and Twenty-first Century technology may produce a monster most hideous. The perspicacious Dave Emory, an American researcher and broadcaster, has stated that in the absence of positive change we may soon face "the total world triumph of absolute evil, forever." From the deep virtual dungeon of my personal experience, I thoroughly agree and boldly bear witness.

    The mock democracy that has cheated, persecuted, humiliated, terrorized, and tortured me is really a "national security" dictatorship, a land surreptitiously controlled by an insolent overclass contemptuous of Law and Constitution, using astounding technology to advance an essentially fascist agenda. It is a vicious, capricious empire, the domain of drooling Caligulas whose unchecked malevolence enlists the aid of legions of cowards, crooks, liars, and fools. It is a culture of contempt, where personal attack supplants rational debate, where artificial distinctions abound while valid ones are ignored. All is arbitrary here. Everything is relative. Law, ethics, and very reality are defined to suit the nefarious purposes of those in power. My America is holographic, virtual. The faces that pretend to rule, the stentorian voices that speak to and for the people, the flags that flutter so high above our heads, are just as unreal and unreachable as those guiding principles now buried beneath heaps of self-interested rhetoric and pervasive apathy. The pretty, pithy phrases that so enthralled me in my youth -- "a government of laws, not of men," " the equal protection of the laws, " inalienable rights," "government of the people, by the people, and for the people" -- echo hollowly now in my ears.

    An intangible Berlin Wall surrounds my America, an invisible Iron Curtain. I left my native land three times, seeking political asylum in the Netherlands, Denmark, and Belgium. In corruption and cowardice, those enlightened nations thrust me three times back into a virtual hell from which I can no longer even hope to escape. Virtual America, through its very palpable power, has spawned Virtual World.

    I am a non-person, ignored or rejected by all, frustrated in my every earnest effort to obtain effective advocacy and justice under law. Define me now as an anti-American American citizen. I have become an enemy of the United States, not by any primal intent or plan of mine, but by the inhuman designs and machinations of my government these many years. One cannot love a government that abuses the human rights of its people and assiduously avoids accountability, that rewards selfishness over service, that abandons principle and enshrines expediency.

    I see my government now attacking the poor as it has attacked me, stealing the liberties of others as it has mine, punishing victims while rewarding scoundrels. I see the people unaware, numbed, somnambulating. Hobbled as I am, there is little I can do to help. So isolated am I that I cannot even obtain information about United Nations human rights complaints that date back to 1991. I have voted three times with my feet. There is nothing here that makes me want to stay. Were I well enough and wealthy enough, I would surely shake from my soles the dust of this cosmically disappointing and dangerous place.

    As an individual, I am no more important than all the other brave souls of earth -- most of them enduring far greater pain than I -- who may be considered Prisoners of Conscience. The significance of my circumstance lies in the power, contumacious attitude, and tyrannical intent of those who oppress me, and, as well, in my utter abandonment by those persons, organizations, and governments who carry the standard of decency and humanitarian concern. My experiences bespeak a serious breakdown of those systems -- state, national, and international, public and private -- that are supposed to control abuse of public power.

    The sad reality is this: in practical terms, there is no United States Constitution. Those who really rule here are not elected by or accountable to the people. The Bill of Rights is contingent, circumstantial, virtual. What has happened to me -- much more than there is room here to tell -- can happen to anyone. Human rights, human liberty, security of mind and body, and the very concepts of dignity and decency may be lost forever.

    I appeal to all who read this to hold my nation, as well as the European states against whom I have a cause of action, fully accountable under the international human rights agreements to which they have freely assented. Throw open the curtain. Let in the light. I have dignity, integrity, and intellect. Let them be recognized. I have charges to make. Let them be accepted and investigated. I have truth to tell. Let it be heard and understood. Let Virtual America actualize itself. Let Virtual World come to its senses, while there is still time.

  • You may not be considered a disgusting slob on Slashdot, although the fact that you're posting anonymously indicates that you yourself realize how crappy that is.

    Raves are all about having a place where people aren't judging you on every little thing you do, how you look, dance, dress, or talk. They are a place where geeks can have fun and not be judged by people with nothing better to do than worry about what's cool.

    Please don't take your troglodytic views to any raves. Raves are a beautiful thing, don't ruin them by making them another place where coolness is the concern, not happiness.

  • The idea was to create a "fart thrower," a flashlight sized audio device that could throw pre-sampled and newly sampled sounds across a classroom. <br><br>
    I followed up with Media Lab about this possibility and at the time (summer 1999) they were predicting two more years of development before it was commercially viable. Mattel wanted a toy for Christmas, so no go. Oh well- short sighted (sounded?) American business strikes again.
  • Uhm, wasn't there a Crackmonkey list thread about this? Something about 7hz? The C source that was posted contained this comment: /* Emits a 7-Hz tone for 10 seconds. True story: 7 Hz is the resonant frequency of a chicken's skull cavity. This was determined empirically in Australia, where a new factory generating 7-Hz tones was located too close to a chicken ranch: When the factory started up, all the chickens died. Your PC may not be able to emit a 7-Hz tone. */
  • This is of course a blatant invasion of customers' privacy. It is none of my supermarket's business what I look at, for how long, how quickly I walk through different aisles, the route I take inside the store, etc. This is why I shop only in small markets-- only there will you find a respect for the dignity of human life in this modern world of impersonal, eploitative Albertson's stores.

    Don't you think you're being a little melodramatic? Consider: The stores aren't interested in you, specifically. They're watching traffic patterns in their store, looking at which products and marketing techniques tend to grab attention and keep it, etc. I'll grant you that small markets are more personal places; that's generally true of any establishment. But let's not confuse marketing research with Big Brother. They have no way of tracking you as an individual.

    Except maybe through your Safeway Club Card. ;)
  • The concept is sound.

  • There definitely was a "sonic drill" article a few months back. It had something to do with the particular shape of the focusing chamber (I don't remember the shape, was it bell-shaped?) defeating the formation of shockwaves. These were explained as the primary loss of energy during the creation of a high energy directed sound stream... It might have been in Popular Science. Still, this is supposed to be much better in terms of control.
  • You could really mess with someone with a personal size one, make someone hear shit no one else could hear.

  • by slickwillie ( 34689 ) on Sunday August 27, 2000 @10:11AM (#824355)
    I'd like to have one mounted on my car. Then, when one of those "boom-box cars" rolls up next to me, I'll point my sound cannon at the driver and burst his eardrums.
  • The most interesting aspect is that you can now do without headphones in public places; for example, talk-show hosts will no longer need those annoying security-men-like mini-headphones they wear.

    Think about international committees (like UN sessions, for example): no more need for headphones. Each ambassador will get his own personal translation "beamed" directly to him. How convinient!
  • Let's say the president of a corporation is giving a speech at a banquet. A disgruntled employee decides to have some fun -- so he brings along his Audio Spotlight and aims it at the president, playing his favorite Hitler speech, while at the same time using another Audio Spotlight aimed at the audience to cancel out the president's actual voice, so that the audience hears nothing but Adolf at his best...
  • With this technology, I could play QIII with Earth Shaking Subsonics and blood curdling explosions, and A) Not wear headphones while B) not disturbing my co-workers.


    -- Crutcher --
    #include <disclaimer.h>
  • Why does it always have to be either all-out capitalism or all-out communism?

    If you'd take a look at most European economies, you'd see how a mostly free economy, regulated only to prevent the corporations running rampant and to run (fund) good public services, can exist without being oppressive, "Russian" or communist.

    And the existence of public services does not mean that private entrepreneurism has been eliminated. For instance, in many countries public healthcare, or in one of your dirty words "socialized healthcare", exists but that hasn't prevented private hospitals and clinics from prosepering. On the contrary.

    I'd say a system where you can start up your own business and at the same time remain relatively free of fears of "losing your shirt" if you fail, encourages more entrepreneurism than a cut-throat, do-or-die capitalism. Knowing that you can apply for state help in paying your debts, getting housing and healthcare encourages people.

  • The article states that the power consumption is similar to conventional speakers.
  • What if you could reverse this effect, creating virtual microphones with a focused array of microphones. Today you can buy simple array microphones intended for desktop use (from Labtec, for instance), but imagine if you really could have "spotlight" microphones of the same accuracy as these speakers...
  • This system won't be subject to the law you suggest for traditional loudspeakers. Since it uses nonlinearity in the air, you can't make a direct relation between them, but... Sound generation frequency range is directly linked to the size of the 'virtual antenna' you create using ultrasounds, and this size is limited by two phenomena : diffraction and attenuation. So to lower the cutoff frequency, you have two solutions : limit the diffraction of the ultrasonic beam (i.e. increase the size of the transducer) or increase emission level to counteract attenuation (i.e. you reduce sensitivity), so the problems are the same, but for very different reasons!
  • by Chris Johnson ( 580 ) on Sunday August 27, 2000 @12:51PM (#824363) Homepage Journal
    It's quite possible that the device's direct beam could induce extremely severe headaches, either slowly or even right away. Supersonic frequencies are picked up by humans through bone conduction and not really sensed as sound per se, but they do play a role- when I want my stereo to convincingly reproduce the tonalities of incredibly loud sounds, I develop the high-frequency capabilities until it's able to produce very strong ultrasonic output, across the whole signal chain. This is known to be fatiguing to the listener- you have to rein it in quite a bit to allow continuous listening, because some sounds (for instance, abrasive raw electric guitars through peavey amps) are intensely fatiguing to the ear themselves.

    Do these MIT speakers kill bugs? Do they cause dogs to howl and cats to hide under the couch? The parallel to a spotlight is apt- it's not safe to look directly into a spotlight.

  • Reminds me of the Dilbert cartoon...

    "Are you an idiot?"

    "No, I'm an engineer. Common mistake."

  • Good idea, but I don't think it could be useful for such an application : To achieve active noise canceling in a volume, you need to create a wave with the same wave vector (i.e. that comes from the same direction) with opposite phase. The proposed system does not provide a flexible way to modify this wave vector. Sound generation happens in the axis of the transducer, so the direction of wave can't be modified. Traditional loudspeakers (and A LOT of signal processing ) provide better flexibility : an array of loudspeakers allows you to create the wavefront you need.
  • Oh please give me a break. As a informed member of the public who actually knows history I say you are really, really, really stretching it big time.
    Ok for your information this can be seen in any number of old publications I suggest the major ones from the 1920's and before. In particular the Ivory soap compaign which was essentially a false one. They advertised that their soap was in fact incapable of sinking in a bathtub of water. There was a well known political cartoon of the day (I believe in the New York Times) which was entitled "The day a cake of ivory sank" which depicted a great deal of confusion and shock that it did indeed sink.
    Take note of the first ideas and usages of choclate cocao which said it was a good medical aid and that it could be used to regain health. Of course it was a blatant lie and almost everyone knew it.
    The very idea that this stuff actually defrauds people is silly and overstated. I have a relative who actually works in the higher ranks of a food distribution company who does this stuff. It's only marginally effective in getting more money in anyone's pockets. American consumers who are likely to be defrauded are usually the first people to do their homework and go for the biggest bargains using cupons, special deals, shopping around, etc.
    Marketing is only effective as you make it. As I have pointed out in other posts here the one true constant in the who affair is the fact that people are not stupid and eventually figure things out. Once they figure out that they were gyped they usually learn their lessons and get the cheaper product. It's at worst a trial and error process that works well most of the time.
    If you are making broad reaching claims I was hard evidence that the problem is as bad as you claim. Like many slashdot posters you are full of gloom and doom because you perceive a problem but offer no plausible solutions to actually solve it in any convincing way at all. It's really rather funny if you think about it.
    In fact repeat the folling mantra over and over again at least 5,000 times a day (lotus position completely optional):
    "There are no effective conspiracies; the world is not out to get me. I am not Fox Mulder and never will be."
    That will keep you sane. Also I would recommend to subscribe to the psycho-ceramics mailing list and then you can laugh at your fellow kooks, loons, and irrational, uninformed idiots who believe everything is a conspiracy. My personaly favorite was the one about the (then) Soviet genetically engineered woodpecker like radio device that was trying to match resonance pitch inside the human skull for slow torture/death. Rather a funny little thing.
  • Can you imagine the spam potential? Ugh...

    Line of site conversations? Across-the-room whispers? Let's get a wrist-watch sized transmitter...

  • That would explain why nobody hears those voices that order me to kill.
  • At the very least, you could mess up the targeting systems with excessive vibration.
  • Tesla was doing things like focusing sound decades ago. He caused a couple of minor earthquakes with it too....

    The concept is sound. I just wonder how long before we'll have high-powered sonic drills, like in the sci-fi movies.

    1. The sound level is 80-90dbA. This isn't very loud: about the level of normal conversation at best. You throw that at a wall, and let it disperse, and you now have a whisper. They'll have to make it a lot louder, and that will be difficult because...
    2. The sound is created by generating a LOT of ultrasound, then letting it create mixing products in the audible range. Let me explain:

      Given two signals at frequencies f1 and f2 impinging upon a non-linear transmission element, the resultant signal will be composed of four frequency elements: the original f1 and f2, and two new elements (f1-f2) and (f1+f2). The power in the original signal will be split between the signals. The amount of the split depends upon the magnitude of the non-linearity: a completely non-linear transfer element will completely remove the origional elements, while medium that is only slightly non-linear will transfer only a little power.

      Now, the problem is this: air isn't very non-linear. So, to get a watt of audible sound, they are going to have to push, ohh, say 10 watts of ultrasound out of the speakers. One watt goes into sound, nine goes into heating of the air as it absorbs the ultrasound. Just what I want at the next (already smoky and hot) concert I go to: a megawatt of heat being added to the air!
    3. Given the general level of paranoia around here, I'm suprised nobody picked up on the fact that the same phased-array techniques that allow this to work can be used to make a highly directional MICROPHONE. Imagine one of these set up in a public place, suitably camoflaged behind ceiling tiles.
      Hey Joe, let's punch up what those two are saying: they look like dissidents

  • I'm sure I remember reading about this in one of the major science-for-the-masses magazines several months ago.

    Still, its an interesting idea. Anyone got any ideas for a really good use for this?
  • Put this setup in theatres. They claim you can make sound "come from" anywhere you want with those things! With one sound system, you can get sounds coming from anywhere onstage, from the audience, or let different parts of the audience hear different things! The possibilities are endless. Most reasonably well equipped theatres now have something like a six or eight speaker system to place sounds where they want, but this could do all of that and way way more.

    I meant acting theatres, not movie theatres, but I suppose both could get the same sort of use out of them...

    Not to mention, I don't give this too long before enterprising rave promoters start using these things. Right now there's a lot of use of stereo tricks in different sorts of techno, but I can hardly imagine what you could do with this sort of setup.

    Of course, it'll likely be a while before speakers like these are made with the sort of power you'd need for it to be practical in a rave.

    Or, how about hands-free phones that don't even need headsets - they just project the sound to the area around your head only.

  • Could I use this technology to blame farts on other people?
  • Weirding Modules...sweet! I wonder if my name is a killing word?

    "Long live the fighters!"

  • by mmca ( 180858 )
    Damn! I just got Dolby 5.1 and now I have to upgrade again!
    Atleast this should make placing speaker on the wall a lot easier.
  • Putting bass transducers under seats or on floor joists will take care of the rumbles below 440Hz.

    These are very cool little disc-shaped transducers that are starting to get affordable

    Strategically placed, directionality does not seem to matter in the lower ranges (at least for me).

    ...Mo$eisley spaceport; you will never find a more wretched hive of scum and villainy.
  • Been there, done that...

    We called it the 'Weirding Way'

    Hehe, this will blow away 'Geeks with Guns', literally.
  • Further to your these greate points,

    I'd ask the leading question "which came first
    acid-like filters in photoshop
    or acid?"

    Essentially, does our technology allow us to envision new things?


    Do drugs inspire new these new technologies?

    And if these technologies could be considered to be analogous to a psychoative drug then how does that tie into the notion that evolution of conciousness throughout all organisims and throughout the history of humanity has been through the mechanism of consumption/use of 'psychoactive' substances by these organisms.

    I.e. whatever molecule that caused some tarsir to 'get a little high' and modify it's conciousness over 100 million years ago which eventually lead us humans as the (socalled) peak of conciousness and
    could lead to a future computer-created reality that is just as

    Too much MAPS for me!
  • by empesey ( 207806 ) on Sunday August 27, 2000 @09:33AM (#824380) Homepage
    Marketing will have a field day with this. In grocery stores, each aisle will have secret messages aimed at areas to suggest you buy certain products (maybe even aimed lower, for the kiddies).

    How long will it be before satellites can beam down messages to whole geographic areas?
  • This is not new at all. American Technology Corporation [atcsd.com] already has such a system called Hyper Sonic Sound (HSS) [atcsd.com]. Their site also shows that they have filed for patents [atcsd.com] as early as July 1996 (first patent allowed August 1998 [atcsd.com]). I hate to break everyone's excitement, but the other thing about this company is that they don't manufacture anything themselves: they only license the OEMs (at least for HSS). It is interesting to note that one of their current contracts is to implement and test HSS technology for use on Navy Ships [atcsd.com]. I first heard of this technology about 5 years ago, to be honest, I don't know why more hasn't been seen of it.
  • Better yet, why don't we just engineer car speakers to aim their audio into the car compartment only? That way they can listen to their annoying Busta Rhymes as loud as they want without disturbing those of us with good musical taste.
  • A haunted house designer wanted the effect of whispering in peoples ears to freak them out. This would probably work perfectly.
  • a crowd of WTO protesters... (with a low-frequency beat wave) to zap individuals. Yeah good idea! hit the protesters with a BEAT WAVE and get them all to dance! It should be hard for them to destroy starbucks stores when they are shake'n their bootys!
  • There is a company [atcsd.com] that is already licensing products using the interaction of multiple high frequency inaduible waves to produce focused audible sound.
  • remember that game? the atreides had sonic tanks, with what looked like a satellite dish on top.

    they werent the best weapons (no armor) but nice attack

    i think red alert 2 might bring those back on the side of the allies

    and while i'm offtopic, i'm not sure how useful it would really be to start a resonant frequency in a tank... given earplugs for driver/gunner just how much damage could it do?
  • or for on-the-fly translations. you could wear an "english" tag on your person, then the speakers aimed at you would only send you the english version, while your fellow spanish-speaking diplomat would wear a spanish tag and would get the spanish version broadcast at him.

    as for weapons, maybe an ultrasonic version could be developed to guide attack dogs to a specific target in a crowd, similar to the way radar was used to guide German bombers in WWII. (though a single radar signal wasn't directional, the net effect of 2 or 3 signals was)
    or an ultrasound version could be created as a tripwire (break the line-of-sound, alarm goes off)

    should we be patenting before posting?


  • I saw this last year on Tommorows World. They thought it could be used on a dancefloor, to focus the music on the couple dancing, not blast it all over the ballroom. Think of having several couples dancing to different music. Or maybe advertisers focusing the adds on just a few people. And I guess it would be better than a loudhailer, you could say whatever you like and only the listener woudl get it.
  • Not so sure I believe in them, but that's another matter, I suppose

    It does work but I don't know what they're talking about when they say "nodal points."

    Here's how it's actually supposed to work: you wear headphones with a realtime DSP built in; the DSP tracks what is going on around you and calculates a sound that is 180 degrees out-of-phase with it.

    A very simple example: if you had a sine wave being produced in the room, it would generate another sine wave that is at an amplitude of -1 when the external sine wave is at an amplitude of +1. These two amplitudes cancel each other out, and you get an amplitude of 0.

  • Strange I remember seeing this story on tomorrows world quite a while ago. So I decided to check on their web site.... And found this story dated the 12th January 2000: Sound Beam [bbc.co.uk]

    It's good to see that Slashdot is there on the cutting edge of technology ;)

    Having said that, the sound beam did sound pretty cool but when it was reviewed in January. It had some problems with serious bass noises, but would be a wonderfull invention for clubs where the dancefloor could be loud, and still have quite areas to chill out and actually talk to people (no there's a novel concept).

    Manic Miner.

  • Having not the slightest idea what country and what area you live in I am going to make some big assumptions about you:
    1. You live in a town of at least 100,000+ people
    2. You live in the USA
    3. You have multiple grocery stores
    4. at least one of the stores in item 3 has in fact some ability to have lower prices than the others.
    With this these conditions met you have to realize a few falacies. In principal ther is very little alternative to capitalism that dosn't really royally screw the little guy. If you look at *history* you see that every stinking revolution, war, brawl, battle that was ever fought for the cause of the common man was in fact a cause that tghe common man never really got a fair shake in. American revolution? Nope the revolution was actually fought and actually started by a group of wealthy arrogant American tea merchants who didn't want the British dumping low priced goods to the Americans and actually give them much cheaper tea. The Russian revolution of 1917 in fact was nothing but a farce "Bread, Land, and Peace" didn't help the millions of starving Russian peseants who still got screwed like they did under the old system the Czar had in place except they got the random political pruge and their leaders thinking they were in complicity with the "evil" rich (how they equated farmers with the rich I don't know)
    Communism is a total flop in almost any country that uses it. Basically the little guy gets, screwed again, and again, and again. In fact the US is the fairest when it comes to helping the little guy not loose his shirt or tax the hell out of everyone or make them wait in long, long, long lines for 5 hours just to get a couple of bruised potatoes before they can actually eat anything. A system which supports lazy people and industrious people and pays them the same damn wage and then productivity suffers and everyone looses. Look at the construction of the ISS and the recent Russian addition. Ever wonder why it took so long? Well the most recent addition was given to the Russians to work on their own whereas the rest were basically used with the Russians as consultants not the sole contractor. They fubbed that one up royal.
    I don't make a whole hell of a lot of money but I don't wish to go into communism where there are still rich administrators and even more of my money is gone.
    Grocery stores are not in the business of stealing the bread before it gets to you in any way. If you don't like the grocery store that you shop at go to another one and shop there. In may area alone There are at least 3 large grocery stores that sell anything that you need. In fact 2 are in walking distance from my home. And yes I must admit one of them does gouge the people but if they do they start to loose their customers and they go to the other store which is happy for their business. Then the store changes that particular policy and then gets some customers. Basically there is something called elastic and inelastic demand. Food is inelastic for the most part for the necessities but we usually we have choice. The more speciality items that are the focus of most of the marketing research (like nacho flavored cookies or whatnot) are elastic and if it's done improperly they loose and it's all over.
  • I think that young children are probably very susceptible to this sort of thing. Children are unbelievably malleable.

    Furthermore, there are situations (most notably, the Nazi regime) where millions of educated and intelligent people became entranced by the illogical ravings of one man. There is plenty of anecdotal evidence that thoroughly intelligent people were completely oblivious to the truth (even though it was quite obvious).

    Of course, I don't think advertisers are quite this skilled; but still, things like this can happen.

  • Actually, we really made our mistake in 1944 (I believe I have that date correct). Ho came to the US and asked for help in negotiating a peaceful settlement with France. The US government pledged their help. However, for some reason (I don't remember what it was), the US Army *liberated* French POWs and gave their weapons back to them. As far as Ho was concerned, he had been betrayed by the US and by democracy in general. *This* is what really turned him against us. If it hadn't been for this, things might have gone much better.
  • I'm not an audio expert by any means, but isn't audio below a certain frequency nondirectional - rather, the ear isn't really able to percieve the direction without some higher frequency information along with it? Consider the subwoofer, which can be placed nearly anywhere in the same room with the rest of a system.

    I'm getting well over my head here, and this is quite possibly a load of something, but perhaps some sort of modulation in the 'beam' combining with a separate carrier at a proper frequency could create the information which otherwise couldn't be transferred. Since the directional information doesn't need to be there, it wouldn't matter that it's the product of two sources.

    Again, I have to disclaim this as possible total BS - I don't have a clear enough understanding of how it works, but it seems that something like this should be doable considering the rest of what they've accomplished :-)
  • Yes, but one of the stated goals is for people in cars to be able to listen to music independently.

    Additionally, where do you get the idea that removing 250-400 Hz band wouldn't be noticible? The lowest note on a piano has a fundamental frequency of ~27 Hz!

  • What well-respected audio company got it's start at MIT? Bose!

    Is Bose a sponsor in this effort? The audio projection trick sounds a lot like Bose's bouncing audio off of walls and the like. And Mr. Bose is a grad of MIT.

    If this is the case, I'm unimpressed.

  • A past PC Magazine article, perhaps? Sounds familiar to me also..
  • The universe is a big place. I guarantee you that there is much left to discover, even with mere thought experiment. For example, there is still a great deal to be done with understanding the application of basic anatomy to playing musical instruments. Dorothy Taubman has done much of this for piano while Claude Gordon has done it for trumpet. What about Violin? Harp? Theremin?

    Then, there are basic questions of philosophy. This realm of discovery is almost all thought experiment, and can actually lead to new discovery in the physical realm.

    Furthermore, never discount the ability of "untrained" laymen to learn and comprehend.

  • This is why I shop only in small markets-- only there will you find a respect for the dignity of human life in this modern world of impersonal, eploitative Albertson's stores.

    The smaller stores don't do the research, but that doesn't mean they ignore the findings of the research.

    Next time you go to your favourite small market, pay attention to how many left turns you make versus how many right turns. You'll likely find the store is set up to encourage you to walk around the store counterclockwise. That's because one of the findings of these laboratory supermarkets is that people are more comfortable if they make a lot more left turns than right turns.

    Also, the snack foods, chips and stuff they want you to buy on impulse, tend to be placed along the leftmost aisle, so you come to it last and have less time to reconsider and put it back.

    Don't ask me why this is, but it's one a them thangs. I wonder if the opposite holds true for left handed people...

  • by Art Tatum ( 6890 )
    And I also wonder how on earth they can use this with John Coltrane if the lowest frequencies are "in the hundreds of Hz". Seems kind of useless for music to me.
  • It would not go unnoticed that there were large soundwaves at work. As soon as they hit their target (bowels, ears, etc.) they will bounce off and be audible elsewhere.


    "You can't shake the Devil's hand and say you're only kidding."

  • Which is why Nike is a zillion-dollar company right now, even though their shoes are no better than what you can get for half or less the price.

    It's called disinformation that's what. It's not subliminal messaging in the least. It's lieing pure and simple. It started with Jabul "Honest" Wakkiem the salesman of pots in Summeria and it's going on today with Nike except Nike has more money.

    Which is why Nike is a zillion-dollar company right now, even though their shoes are no better than what you can get for half or less the price.

    That's different how from saying that Joe Domagio endorces this product or service. Still not a conspiracy and still not subliminal it's an entirely misinformed opinion. People have done that since the 1920's or even earlier. Check out an archive of old newspapers and look at their advertisements the same old stuff.

    There was a study a while back (Sorry, no links or references) that found that users of expensive athletic equipment (mostly shoes and cleats) actually injure themselves more often and worse than users of cheaper stuff. People with cheap equipment didn't have as much trust in their equipment, so they exercise some caution. People who have spent four or five times the money think they must be getting much better protection, so they play more dangerously. Of course injure themselves more, because the more expensive shoes are no better than the cheaper ones.

    So I would (if I didn't know better) think that if I paid more money for something that it should at least work better. It's just a little misplaced logic. That dosn't qualify for conspiracy status quite yet. You have to have the unexplained concept or the hard to disprove little kernel of doubt. I don't see it.

    Fact is, the extra money they spent doesn't go toward making better shoes, it goes to putting Michael Jordan's name on the side of the shoe. And that's what sells shoes.

    I have no beef with that. Most people in most industries in the past didn't give a shit about their products until people got irritated and the laws were eventually changed. See the creation of the Pure Food and Drug Act under Teddy Rosevelt.
  • NO.. he did no such thing.

    As for all the great thigns tesla did..
    he DID do great things.
    But people all too often confuse what he did with what he was trying to do.

    Tesla was a tinker, a hacker. Read his biography, it's great. He gets overlooked in the education system largely, and ignored at the smithsonian.
    Marconi's patents were revoked and attributed to tesla.

    He did not focus sound, though, at all. NObody has ever done this before.

    He did run low frequency sound through a pole sunk into the ground, and made nearby buildings shake by hitting their resonant frequency.. but this is exactly the opposite of 'focusing'.

    Sonic drills.. that's starting to happen already. Also.. I believe a year or so ago someone figured out how to create a standing sonic wave in a chamber (has to do with chamnber shape). This is really cool.. could be the workings of a motionless pump or something (standing shockwave.. layer of compressed air that can be 'moved and rotated' by computer.
  • Could someone please help me buy one of these for the guy in the cube next to me!?!?!?!
    If I have to hear Limp Biscuit one more time . . ..
  • Directional sound doesn't really help much there. Let's say the sound is directed straight at the driver's head. What energy isn't absorbed by his eardrums will continue on in the same direction and eventually outside of the car. What you would really want is better sound insulation (luxury cars are getting pretty good about this).

    Mind you this still could have its uses. With a little bit of effort, you could get the same loudness from a 50W source as, say, a 150W source, since you don't have all that omnidirectional sound energy. Just imagine if you could do the same for the sun :D

  • Don't you think you're being a little melodramatic?


    Consider: The stores aren't interested in you, specifically.

    No, they're not interested in me, or in any other of their customers, as anything more than a guinea pig to experiment on so as to manipulate their behavior for the benefit of the stockholders, and the detriment of the customer. This is a problem.

    And it also neatly gives lie to the religion of the "invisible hand of the free market". Those economic actors who have the most power use their power to deform the free market, not only by distorting the information available to customers, but also by manipulating their behavior.

    They're watching traffic patterns in their store, looking at which products and marketing techniques tend to grab attention and keep it, etc.

    Information which they plan to use to rip me and millions of others off at a future date. Information is crucial to waging war; the class war is no exception.

    But let's not confuse marketing research with Big Brother. They have no way of tracking you as an individual.

    Their objective, again, is to manipulate us, to control us. My interest in preserving my privacy in this case is the same interest a country at war has in keeping its sensitive information secure.

  • that used to be in the helpfile for borland C++ v2

    *Not a Sermon, Just a Thought
  • ... Sennheiser Electronic demo'ed a prototype of a speaker with the very same technology earlier this year at the annual meeting of the german Acoustical Society (Dega). So this is not really groundbreaking news...

    It's strange actually to see someone move the 'speaker' and you can hear the sound source moving through the room...

    If you look very closely, you can see the speaker here:


    It's only a view from the side, though (N.B. the speaker is the flat silver thing that doesn't look like a speaker ;) )

    just my 2 ningis

  • by Electric Angst ( 138229 ) on Sunday August 27, 2000 @10:40AM (#824409)
    were drugs introduced into our society in order to prepare us for the emergence of technologies that would simulate heir same effect?

    Yes exactly. As a matter of fact, I am the intelligence behind such an operation. I personally manipulated the DNA of the first hemp plants to ensure that they would produce THC. The actual process of fermentation, that was me too. It really just involved fucking with some yeast. Of course, then I introduced it to man, in the forms of mead and wine, long before recorded history. I also did LSD (at least, I did the real work behind it. In fact, you name it, I put it here, so your feeble little minds wouldn't explode when you saw a laser light show.

    Believe me, before I altered space-time, the Disney light parade was an absolute killer.

    (Yes, of course this post is sarcastic. My user number is far too high to have been able to do that stuff...)
  • Ya ever gone to make a presentation with your handy portable computer projector, and used a white wall because no screen was available? It seems that this would be a practical extension--mount a sound projector on the normal projector, and you bounce the sound off the wall, as if it's the source.

    Why is this cool? Added realism--the sound is coming from the image itself. You get an instant-setup movie-theater, where traditionally the speakers have been behind the screen. Portable video conferencing, with the audio coming from the person talking...yow!

    My only concern is that it only goes down to "a few hundred hertz" currently. Gotta lug along a subwoofer (but at least that sound is basically non-directional anyhow, right?) for strong quality sound.

  • c.f. Eric Cartman finding the "brown note" and rewriting the sheet music for the world recorder meet. Kenny G and Yoko make the world go apeshit...

    Also, wasn't mark mothersbaugh (sp?) of devo fame looking for this note?
  • Well,

    IIRC /. is also repeating itself. Again. Tho the inability to search old articles (hey, Rob! fix this) makes it hard to verify.

    But I definitely do recall a story about a big multi-speaker array; record localised sound using an array of mikes, and then play it back on the array to recreate the sound coming from the old location.

    Now all we need to do is figure out the phase interactions and you can make the array move the location anywhere you'd like.
  • They also have them at a CD store in the mall near my house. But, I wouldn't say that is the same thing as what is being researched at MIT. It sounds like it's different in concept, or at least scale.

  • by EricEldred ( 175470 ) on Sunday August 27, 2000 @01:40PM (#824414) Homepage

    Can this technology be used to cancel noises as well as generate sound?

    I am thinking that current noise-cancelling technology seems to rely on headphones, since noise is generally omnidirectional. But if this technology were used to determine the direction of the noise source, and shift phase of sounds so the sounds appeared to be coming from the same direction, then one might not have to use headphones.

    For example, in a cubicle there are noises all around, from telephones to people talking, and it would be extremely useful to be able to selectively tune out the noises and work without headphones. Currently, I believe "noise cancelling" area systems just generate white noise, which doesn't fix the problem, only create more.

    The lower bass tones could be handled in an area system, I think, because they wouldn't be so directional.

    I mean, doesn't the world suffer from increasing amounts of "noise pollution" as machines proliferate in our increasingly urban environments? Many people including myself would love to be able to take action to control this environment for ourselves and filter out the annoying noises. A much better use than increasily annoying sales pitches beamed directionally at us without any choice.

  • Those sounds systems are about forcing others to hear the music. They wouldn't go for anything that couldn't be heard outside the car.

  • Do I even need point out the possibilities opened up to the pranks industry?

    Projected flatulence sounds real and produces real and embarrassing results! Use with "Flatulence Spray" (Item #4827)

    I can't wait . . .
  • You know, there's a difference between a socialist government and a communist economy.

    Canada and France are two examples of countries that have had socialist governments on and off for years. But these are not Communist countries. There's a big difference.

    And how about Cuba - sure, not much for freedom...

    Please re-read that sentence. Then read it again. Repeat as necessary until what you just said sinks in.


  • I think a much better way of doing that will be once we have mastered cybernetics, neurology, whatever, and can simply wire our brains to eliminate specific sounds just by thinking about it. Okay, sure, it's a ways off, but still...
  • i can picture that now, mom walking through the grocery store with junior and they stop in the cereal isle. "psst, hey Kid! You love me right?", says a loveably cartoon character to the kid, "then why dont you ask mommy really nicely to buy me?". Of course the parents cant hear this conversation because its aimed at around their knees... Suddenly the little kid needs the box of cereal because he doesn't want mr.[insert cereal mascot here] not to like him anymore. you did that, you'd probably make a fortune... until people found out that is...
  • If I'm understanding it right, this could be pretty good for cubicles, eh? I'm thinking that I could have a full sound experience, while not disturbing my coworkers in the adjacent cubes -- cool!

    Alex Bischoff
    Interested in building a roof over your cubicle? [slashdot.org]

  • ... it'd be a boon for the hearing impaired in public spaces. Amplified sound targeted to where they are sitting/standing.

    I wonder if it could also be used as a weapon. Stun people with an amplified blast long enough to subdue them.

  • Wow, just think of the ventriloquist act I could have with this technology... Look out Howdy Doody, here I come!
  • Can you name a country that has/had a communist economy and a democratic sytem of gevernment? Likely not.

    The fact that you don't perceive this to reflect something fundamentally wrong with Communism is just a little amusing to me.

    Doesn't this tell you something? That maybe people, given the choice, would really rather do without Communism?

    Trying to use Vietnam as an example of Communism that "would've worked" is ridiculous. Vietnam was the Cold War writ small, not some Communist Eden.


  • I love that phrase "Class War".

    What a perfect way to conjure up feelings of fear and hatred while issuing a call to arms for anyone that's ever felt knocked down a notch in our society.

    It's such a clever use of words, but it belies the duplicitousness of the people who use it.

    By conjouring up the image of an invisible barrier that keeps individuals from accomplishing their goals, you provide them with a convenient scapegoat on which to relieve all their frustrations. Hence the use of that dirty word "class". You have no control over what "class" you belong to, because it is forged into your being the day you are born by the evil powers that be. It also quietly discredits the notion that you have control over your own life and determine your own destiny.

    Then there's the use of "War". Wow. There is no more powerful imagery than that of horrific destruction and the senseless slaughter of precious human lives. And by portraying entrepeneurs as cold-hearted, armageddon-bent demon-spawn, you make it that much easier for your flock to forget that their "oppressors" are human too and that they too suffer and die.

    It might not even be such a bad lie, if this rallying cry for the envious wasn't such a dead end. By repeating it, over and over, you start to believe that it really exists and then you are trapped. Trapped believing that there really IS nothing you can do to help yourself. That everywhere you turn, there is some invisible force, plotting to keep you down.

    The reality is, nobody cares about you. Nobody is willing to expend the significant effort to defeat you at every turn because you simply aren't worth the trouble. The only person that really has any vested interest in keeping you down is you, yourself.


  • by TheNightOwl ( 206911 ) on Sunday August 27, 2000 @09:42AM (#824474)

    Hey you over there. Yeah you with the red dress. Come on up front. The bass player wants to meet you.
  • by Anonymous Coward on Sunday August 27, 2000 @09:44AM (#824477)
    It's nice engineering. But as the page itself points out, there has been lots of prior work in this area.

    One very important question is the safety of this kind of approach. The nonlinear effects can't be very efficient, and there must be a lot more energy in the ultrasound than in the audible sound. How safe is it to have large amounts of ultrasound energy beamed at you for extended periods of time? I think I'll stick with headphones.

    As an aside, the trademarking is taking on ridiculous proportions: "Audio Image (TM)"? "Directed Audio (TM)"?

  • by Derwen ( 219179 ) on Sunday August 27, 2000 @09:45AM (#824478) Homepage
    Forget about ad potential, can you imagine standing at a street corner and hearing, "THIS IS THE VOICE OF GOD!

    Actually the article [mit.edu] states that " frequency response, depending on size, extends down to a few hundred Hertz."
    I think people will be more surprised than alarmed to discover that the 'voice of god' is a soprano .
    - Derwen

  • I think people will be more surprised than alarmed to discover that the 'voice of god' is a soprano .

    You mean it isn't?

    Ever see Dogma?

  • I think you're being a bit melodramatic, also :).

    First, the stockholders of supermarkets aren't necessarily "bourgeoisie". You can be a stockholder, too; just buy some stock. And it's possible for a supermarket chain to be entirely owned by individual small investors like you. And the chain would still practice sleazy marketing practices; so, I don't see how there is a class war at work here.

    Also, I would argue that the supermarket chains do indeed exist to provide a service to consumers. Although what the chains want is, as you say, to provide profit for their shareholders, the reason they exist is for the consumers. If they didn't, they wouldn't be allowed to exist in their current form. For example, it appears that Microsoft is currently doing a disservice to consumers, so the US government is considering splitting them up. If the supermarket chains also harmed consumers, the same thing would happen to them.

    Finally, you make it sound like there is a choice between "shop at exploitative evil supermarkets" or "starve". But there are lots of other options. You can get your food from smaller businesses you consider non-exploitative, or, if you really want to, grow the food yourself. These options are perfectly reasonable; if most consumers did not like being "exploited" by the big chains, they would all switch to smaller stores. This isn't happening; so, apparently most people do indeed find the big chains useful and choose to shop there because they feel it's to their best advantage. I don't see any exploitation here.

  • just think of the test cheating potential... why wasn't this around when I was in high school?
  • by friscolr ( 124774 ) on Sunday August 27, 2000 @09:52AM (#824501) Homepage
    consider some of the most common side-effects of popular illegal (in U.S.A. and most) drugs - they alter our perceptions, causing us to see things that aren't there, or hear things that aren't there - "the tree man, it's talking to me"

    now a lot of these effects are being duplicated with technology, only they aren't altering the way our brain senses, they are actually creating pseudo-realities for us to exist in (was that ad on the soccer field really there, or was it digitally placed? did the guy sitting next to me see/hear the same ad?)

    were drugs introduced into our society in order to prepare us for the emergence of technologies that would simulate heir same effect? imagine what the world would be like if we were suddenly introduced to a whole bunch of mind-bending technologies. Drugs (and the knowledge of the causes of such drugs, for those who don't partake) gives us the background to understand these technologies.

    just a thought


  • Just put in a tracking device, several of these spotlights, and a network of audio pickups and you can have your phone calls directed to you with no headset.

    Now how to tell apart the people talking to nothing and the people on the phone...
  • by Claudius ( 32768 ) on Sunday August 27, 2000 @09:57AM (#824504)
    I wonder if it could also be used as a weapon. Stun people with an amplified blast long enough to subdue them.

    IIRC audio weapons have been made with very low freq. audio meant to hit a resonances in people's abdominal cavities. The trouble with the low-freq audio was that it tended to be omni-directional, so it was difficult to aim the cramp-inducing sound field at, say, a crowd of WTO protesters without harming the good people manning the device. One could imagine, however, using multiple, highly columnated, directional beams of slightly differing frequencies (with a low-frequency beat wave) to zap individuals. The resonance is moderately narrow (again, IIRC--someone more in the know please correct me if I'm wrong on this), so the carrier may not need to be of exceptionally high volume in order to drive the resonance to useful amplitudes.

    It's been a long time since I read about these, but if I recall correctly the concept was inspired in part by a chicken farm located near a factory in Australia (perhaps New Zealand). The factory put out steady, low-frequency oscillations at a particular frequency that caused the chickens, when they grew to where their heads were a certain size, to die from having their brains scrambled.

Beware of Programmers who carry screwdrivers. -- Leonard Brandwein