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Targeted Sound Beams
Mr_Kcleen writes: "Wired has a story on using sound beams targeted to only one person. They discuss various uses, from musical performances to possible weaponization." This is another one of those ideas that are right around the corner, really, honest.
I only hope that this won't be adopted by RIAA.
People who like this sort of sig will find this the sort of sig they like.
i hope that explains those voices that keep telling me to horde my precious bodily fluids.
mp3s by me
The New York Times is also covering the article (free reg) or you could just go to The Audio Spotlight's home page for a more detailed account of their technology.
every day, technology brings us a little bit closer to being able to make our younger siblings think that they've gone insane :D
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Finally science has reached it's peak. A surefire way to get the beer guy's attention at your next baseball game. On a serious note, hasn't the pentagon being looking into ultrasound devices for crowd control and similar applications for a LONG time (say 20+ years?) I seem to recall a Discovery Channel special on that a while back.
. .
General - Why we could make a devestating weapon out of that!
Inventor - It's a tortilla maker. .
General - Why yes, but think of the scientific principles it displays!
Inventor - It's a cast iron tortilla maker.
General - We need 800,000 by next week. How does 300$ per unit sound?
Inventor - The Freedom Flattener 3000 will be operational by tomorrow General!
Find out about my new childrens book: SS Death Camp Criminal Batallion Go To Monte Carlo For The Massacre
Pompei's website hase more detailed information of this here: http://web.media.mit.edu/~pompei/spotlight/ here is a brief description from the site. Technology: Because it is impossible to generate extremely narrow beams of audible sound without extremely large loudspeaker arrays, we instead generate the sound indirectly, using the nonlinearity of the air to convert a narrow beam of ultrasound into a highly directive, audible beam of sound. The device transmits a narrow beam of ultrasound (blue), which, due to the inherent nonlinearity of the air itself, distorts (changes shape) very slightly as it travels. This distortion creates, along with new ultrasonic frequencies, audible artifacts (green) which can be mathematically predicted, and therefore controlled. By constructing the proper ultrasonic beam, this nonlinearity can be used to create, within the beam itself, an audible sound beam containing any sound desired. This is presently done in real-time using low cost circuitry, a specially designed amplifier, and transducers developed at MIT specifically for this project.
Saying Java is nice because it works on all OS's is like saying that anal sex is nice because it works on all genders.
Is all the energy converted to the audible range or do we get weird things going on elsewhere in the spectrum? Will dogs bark and birds flee?
Sounds like fun technology. I remember reading about it a while back, but had no idea it was being implemented in commercial projects. Portable mp3 players/discman seems like a better car solution to me, but some of the other applications are intriguing. Time to get myself to Tokyo.
This was reported in Scientific American in 1998. I also recall seeing it in New Scientist, and on the BBC television programme, "Tomorrow's World" at about the same time.
"E pur si muove!" - attributed to Galileo Galilei, 1564-1642
I saw a demonstration of this technology a few years ago at Epcot center, during the Discover Magazine Awards for Technological Innovation. The demonstrator held this paddle-like device with an array of metallic discs on it, and as he turned it slowly across the crowd, you'd not hear a thing until it was pointed at you. Very cool :)
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From the article: Pompei imagined that instead of loudspeakers blaring the same cacophony of instruments to all parts of the room, it would be more interesting to selectively spotlight the soloist to the left side of the audience, while featuring the percussion up front, and then switching them around.
But when I go to a concert, I want to hear all the instruments - without having to move around the room.
Also, I get the impression that current tests are being carried out in silent environments with few obstacles. In a concert, you'd have to crank up the volume of such a 'sound spotlight' in order to hear it over the 'general' sound system. And in a crowded hall, the sound from the beam would be reflected more. This would cause the sound generated by the spotlight to 'leak' out of the beam area, making it less effective.
And (also important in a concert) the audio engineer can't hear what he's doing with the spotlights, making it very hard to get right.
These people are actually doing something very different.
They're taking ultra-high frequency sound which is way out of our audible range, the higher the frequency the more directional (which is why you dont need to worry too much about where your sub-woofer goes) and recreating audible sound by causing what is known as "beats" in two or more similar high frequency sound beams (guitarist will be familiar with beats, as they are very noticeable when tuning strings without a tuner). These beats are obviously at such a high rate when caused by high freq sounds (60khz!!) that they themselves create audible tones.
If you need an example of how directional and effective high freq sound is, there have been numerous problems in horse racing over the last decade with people mounting high-freq sound emitting devices in binocculars which are then targetted at specific horses, causing them to freak out... Several people have been caught out in Australia with such devices.
So, high frequency sound will not travel as far as low freq, but at 60khz, you can put as much power into it as you like and therefor push it as far as you like without annoying to many people, which makes it a hell of a lot more effective than normal "parabolic" cones or horns.
to directing sound with a parabolic lens.
In its broadest sense the problem with any transmitting antenna, be it sound, light or radio frequencies, is diffraction
For a given wavelength the smaller the space you emit the waves from the wider the angle they spread over.
What these people have done is to use the improved diffraction characteristics of high frequency ultrasound, which diffracts far less than ordinary audio frequencies to generate audio sound literally "out of thin air" due to a nonlinear interaction within the air.
Hats off to Mr Pompei, it sounds like a very neat system. (I couln't help the pun, sorry)
Be nice to people on the way up. You will meet them again on your way down!
... an N'Sync'ed beam ;)
The guys you're talking about are using a process which is all done within our hearing spectrum.
The use slight delays to fool our ears into thinking that the sound is surrounding us. The pinnea (ear flaps) are used to channel and delay sound as it enters our ear to give us an impression of where the sound is coming from, so as sound hits our pinnea from one direction, it gets to the eardrum at a slighly different phase than from other directions, our brain learns to interpret these differences and give a direction to the source.
The synthetic version of the process was called transaural. It was written up in the AES journals at least 7 years ago...
Yes, we hear sound in 3d...sort of.
For the most part, (with a few exceptions), most humans are only able to distinguish thing in front of them from things behind them, and its quite easy to prove that we can't guage distance from sound (because we don't know how loud it was at the point source).
However, anyone can train to improve their selective listening skills and achieve more 3d awareness. Its quite a common skill among conductors, musicians, and most of all sound technicians.
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doesnt work like that at all.. your dish + speaker to beam sound to a location doesnt work. cince it is still at slow frequencies it get's messed up and will spread from the mouth of the dish like a floodlight.... tis how sound works... hyper-frequency sound... just below radio waves, have both characteristics... act as sound, propagate like radio waves... and this is what they are using... read the article.
Do not look at laser with remaining good eye.
They discuss various uses, from musical performances to possible weaponization.
OK, I know those damn weirding modules weren't *really* part of the Dune story, but someone had the idea that they would make a great addition to the film, and these folks are obviously on the same track.
**BUSH!** His name is a killing word!
"Beware of he who would deny you access to information, for in his heart, he dreams himself your master."
In the example, you'd have to completly document everything about that tortilla maker:
Where the iron was dug out of the ground. (and probably which shift.)
Where the ore was smelted and refined. (and ditto)
Where it was cast. (and ditto.)
Transportation...
All that ISO-8002 (or whatever) paperwork costs much money. $500 hammers make a nice target for senators who want to look good with "Golden Fleese" awards, but there's a reason they cost that much compared to running down to the hardware store.
One line blog. I hear that they're called Twitters now.
I saw that one... It would be a great technology for use at rock concerts, nightclubs, etc. Zero noise pollution - if you're outside the target area it's completely silent.
:-)
Hell, I'd like one for my living room... the neigbours would probably pay me to use it
I can see it now, because of security issues all sporting events require facial recognition technology. To offset the cost of implementing the technology the stadiums sell the data to advertisers and lease space for directional sound equipment so they can target ads to specific people in the stadium. Or they could decide to target ads to certain demographics. All white guys in their 40's will get ads for Michale Bolton's greatest hits. Bleh
Cat
... and you could have the perfect weapon for getting someone to shut up!
There are many more applications of this technology than the article lists:
Multi-lingual Movie Theaters:
Push a button on your arm rest and get the movie in English, French, Spanish, etc. (or in the original Klingon). Pushing the "G-Rated" button on your child's seat would tune out all those nasty 4-letter words (although visual violence and sex would remain on screen). You could also control the volume from whisper to bone-rattling.
Spot sound cancelation:
Lots of uses for this one. Create quiet zones by coupling with sound cancelation techniques. Imagine being able to punch the "Cone of Silence" (CoS) button in your office when your co-workers are getting a little loud or you need to really concentrate. You could also listen to your favorite music without wearing headphones or disturbing your cube-mate. This would be particularly useful for airplanes. You could engage your CoS when you want to get some rest or simply to block out the airplane noise. The pilot could engage everyone's CoS to nudge people into staying in their seat (if they get up, they get the loud airplane noises again). Or how about for good neighbor relations- are your neighbors complaining that your dog Sparky is keeping them up all night with his barking? Just install the BarkStop(TM) system in your back yard and put the tracking collar on him. All his barking gets muffled. It also acts as an invisible sonic fence to keep him inside the yard.
Super Surround-Sound Home Theater:
DVD's could contain extra sound encoding information to paint the viewing space with individual sounds. All of the sounds in the movie would come from a 3D location in space. This is similar to what the conductor in the article wanted to do.
Point-To-Point Smart Intercom:
Rig an office building with locator ID badges, tracking microphones, and sound projectors. Now you can tap your badge ala ST:TNG and speak to anyone in the building in total privacy. Rig it into the phone system and you can talk to anyone out of the office via their cell phone or in another office building a continent away.
Thrill rides and haunted houses:
Structure the experience by controlling sound location, volume, etc. Easy to make "ghosts" follow behind you, chains rattling above, and so on. Heighten the experience by using selectively transmiting magic frequencies that induce unease and nervousness.
And of course practical jokes:
Echoing footsteps, sqeaky shoes, body sounds, etc. Use your imagination.
The possibilites are almost unlimited. It is funny that what the DOD really wants out of this is a classic SFish Sonic Disruptor.
What I really want out of it is a Sonic Screwdriver.
I.V.
"These laws they're passing won't even compile anymore, let alone execute." - anon
Reasons not to peruse /. first thing in the morning:
I read the headline as "Targeted Sound Beans" and wondered WTF they were doing with Java now??
Remember, good boys don't put beans in their ears!
[Where did I leave my injectable caffeine??]
~REZ~ #43301. Who'd fake being me anyway?
Of course, in Las Vegas casinos the ceilings are absolutely covered with a/v packages to watch patrons, so the security guy mutters in a low voice 'keep gambling'. To which Ned proceeds to spend a huge wad of money.
This 5 second scene pokes fun at so many things at once, I'm always in stitches.
Endless arguments over trivial contradictions in books written by ignorant savages to explain thunder in the dark.
This is going to be most useful for situations where you have multiple, different audio sources in the same area and don't want them to interfere. Museums and trade shows come to mind. The volume application is probably going to be point-of-sale displays.
If Targeted Sound Beams are almost here, can Targeted Advertising Sound Beams be far behind?
Just imagine, you're walking down the street. You hear an advertisement for the strip club half a block down. You try to run away, but the sound seems to follow you. When that ad ends, you then hear the beginning of a new advertisement how to make money fast! You try crossing the street, but the sound just seems to follow you.
I'll see your senator, and I'll raise you two judges.
I played with this at Bose a few years ago, and it's very disorienting at first. Pompei may have taken this further than the prototype I saw, but the version I played with essentially created audible sound coming from the point where the ultrasound beam reflected off of a surface.
It's very odd to play with one of these things. We put on a CD and started waving the ultrasound array (housed in a flashlight body) around the room. I felt disoriented pretty quickly as my brain tried to figure out where the sound it coming from.
One of the more interesting effects, as mentioned in the article, is pointing the array at someone's head and turning the volume down. Only the target can hear, because it's essentially like having a headphone on. The sound it's generating is simply too quiet to hear unless you're less than a few centimeters from the source.
My favorite application for this is car navigation systems. I like the idea of a GPS navigation system that can give spoken directions to the driver without bothering all of the passengers in the car.
Just imagine- some day these things could be as common and annoying as laser pointers. Imagine walking down the street with some teenager 200m away whispering in your ear. It's going to be ugly.
Theyre called "Low riders".
Theyre used mainly by inner-city minorities and retarded white kids who find the cul-de-sac an inappropriate place to express their blackness.
Ever get the feeling that all that bass is being used to compensate for not being held enough as children?
Cheers,
Bowie J. Poag
You could prove that, if sound waves were perfectly linear. But they aren't. Sound media (such as air) are nonlinear, dispersive media, which means that sound of different frequencies propagate at slightly different speeds, meaning that wave packets will slowly disperse in air (or any other medium). If you have any familiarity with QM, it's the same principle that causes matter wave packets to disperse over time. Another example would be the dispersion of a polychromatic light pulse as it travels along an optic fiber. Since light of different frequencies travel at different speeds through anything that isn't vacuum, the light pulse will spread/smear out as it travels down the waveguide. The amount of spread depends on how far the pulse traveled.
A computer can definitely tell the difference between a sound pulse that has traveled 1 meter and a pulse that has traveled 100 meters, even if they are the same loudness when they reach the detector. I bet at least some humans can tell the difference also.
Well, see, you prove it by taking a whole bunch of people and trying a wide variety of sounds at different volumes and locations and getting them to identifiy how far away the sound are.
They won't be able to. The test have been done before, though I can't tell you where right now.
Why don't we use phase shift or spectrum spread?
Because it isn't a reliable indicator of anything. Different frequencies propagate at different speeds, true, but you have to know what the sound is like at the source, and about everything in between - something we do not know reliably. Did you know that a sound coming from a source on a wooden stage will usually reverberate with more of the lows than the highs? If we depended upon sound spread for distance, it would make the sound appear closer. What about audio amplification? Using pretty much any means - electrical or acoustical - the result is a phase shift and a spreading of the sound - something you would expect if the sound is farther away. Also, due to the nature of reflection, out of phase sources that meet at a wall will only reflect their in-sync portions, confusing the distance based on phase for both of them.
What does all this show? That the interaction of sound waves with the surrounding media is so complicated that there is no way to accurately use them to guage distance with an unknown sound.
A computer may be able to tell the difference between a computer generated pulse specifically used for distancing that has traveled 1 meter and one that has traveled 100 meters, but it wouldn't be able to know the difference between a live band heard 100 meters away and one heard 1 meter away.
--From an acoustical engineer
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Want to learn something interesting? Look up "voice to skull" technology. I have managed to find direct evidence (via government websites) of both the United States and Austrailia researching this technology. Patents exist, and can be looked up. The technology is real, as has been known about for a few decades.
It looks like the tin-foil hat kooks may be right.
Two systems exist:
1. Audio over ultrasonic carrier - essentially uses the skull to filter the ultrasonic carrier wave - at that point it is simple bone conduction.
2. Audio over microwave carrier - this one is more "advanced" - it uses frequencies in the microwave region as the carrier wave for the sound. These waves then stimulate the vestibular region of the brain, which filter out the carrier and leave the sound information behind for the brain directly to figure out - causes strangeness to the recipient - a "voice in the head" type sensation. This form of V2S was first noticed by microwave and radar engineers who would "sense" or "hear" (in their heads) "clicks", "pops" and "whine" type noises as the worked around unsheilded microwave equipment.
Both of these technologies are real, as far as I can figure. Neither is "high quality" - but voice quality only (in fact, the microwave V2S system is actually pretty poor quality - rendering the voices in a "growling" type tone - which could be interpreted as "demons talking"). Both have potential "sinister" applications - neither have the quality of use for anything else.
I wish I was making this up - I haven't found anything that says "impossible" yet - but if someone could look into this with me, and let me know that I am wrong, I would love to see the information...
Reason is the Path to God - Anon
dang.