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Directed Sound
Posted by
CmdrTaco
on Tue May 04, 2004 07:02 AM
from the stay-out-of-my-sweet-spot dept.
from the stay-out-of-my-sweet-spot dept.
yawningyellowyak writes "Technology Review has an interesting article on directed sound. Ultrasonic 'sound' is sent out from a 'speaker' and the distortion encountered on hitting the air produces hearable sound, but only in certain spots. You could be standing right next to someone and they would hear nothing.
One step closer to the cone of silence!"
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Directed Sound
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Cone of Silence (Score:5, Funny)
(Last Journal: Saturday July 17 2004, @04:03PM)
Damn. I'm still grappling with the unmistakable cone of ignorance
The missus (Score:5, Funny)
standing right next to someone and they would hear nothing
That would be great if someone could rig my wife up with one of these... the silence would be bliss! :)
Re:duplicate - Link (Score:4, Informative)
(http://www.scitec.uk.com)
Not difficult to find from July 2002.
As seen in this story (Score:4, Informative)
(Last Journal: Sunday November 18, @11:35PM)
"The fine folks at the MIT [mit.edu] Sound Media Lab [mit.edu] 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 [mit.edu] 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."
I also recall another story someplace where a guy was messing with a portable version of this in a mall, spooking people out. Apparently the sound appears in the persons head, but you do know exactly which direction it is coming from.
I can see the potential to harrass politicians and other public speakers right now. It is definitely an acquired skill to be able to speak without stumbling despite that kind of distraction.
Ahhhh (Score:4, Funny)
Re:Ahhhh (Score:5, Funny)
(Last Journal: Saturday July 17 2004, @04:03PM)
Re:Ahhhh (Score:4, Funny)
Re:Ahhhh (Score:5, Funny)
I think you might want to rethink that plan Sparky.
KFG
Re:Ahhhh (Score:4, Funny)
(http://roostme.com/)
Cone of Silence? More like cone of annoyance. (Score:5, Interesting)
(Last Journal: Thursday January 13 2005, @12:25PM)
And we think spam is bad...
A sea of calm (Score:4, Insightful)
Done well, you wouldn't hear a thing; even partial cancellation should reduce the adspeak into something akin to a distant ocean sound.
I think there would be privacy isues to overcome on the part of the Admen first however - remember the hoo-haa over subliminal advertising?
Messin with people (Score:4, Funny)
On the edge psycho person: "Hey, did you hear that voice"
Unknowing friend: "No, I didn't hear anything"
On the edge psycho person: "Quit messing with me man, I can hear that voice a clear as day"
Unknowing friend: "I told you, all I hear is some elevator music"
On the edge psycho person: "AAARGH, get it out of my head, it's telling me to, to, to
Unknowing friend: "TO WHAT, TO WHAT!?!"
On the edge psycho person: "GO TO AISLE 4 FOR A 2 FOR 1 ON LIGHT DAYS! AAAAAAAAAHHHHHHH"
All kidding aside, there actually is a fair bit of harm one could use this tech for. Make the "sound" of high enough intensity, and it would make a very effective, and undetectable weapon.
Re:Messin with people (Score:4, Funny)
(http://www.epscylonb.com/)
so you could use it to kill harkonens...
Re:Messin with people (Score:5, Funny)
One of the guys who was developing it enjoyed pointing it down towards people on the street and speaking to them. He said they got really creeped out and started looking around to see if anyone else heard it.
I think it'd be more fun to involve two people and two speakers. Have a sort of devil and angel think going on.
"Kill that guy over there!"
"No, don't do it"
"Go on, don't listen to that pussy!"
Re:Messin with people (Score:4, Funny)
Hope it will work for "boom cars" (Score:4, Interesting)
The Lucas Sound Studio @ Disney (Score:4, Interesting)
(Last Journal: Wednesday February 01 2006, @08:39AM)
* There's something similar to this. You put on headphones.
* You're in a booth about the size of a small 1/2 bathroom.
*It goes completely dark, but you are told to close your eyes for an even better effect.
You then proceed to "become a CEO" for a day of a Fortune 500 company - you get your hair cut and blowdried in the boardroom - you CAN FEEL the scissors and hear them close to your ears and atop your head. Then you can FEEL HEAT from the blowdryer - and it's nothing but sound rather an auditory/perceptual illusion.
Imagine if this could be done with the directory sound.
But Max, the Cone of Silence doesn't work! (Score:3, Funny)
(http://www.unity08.com/)
"Uh.... what was that, Chief?"
More Details... (Score:5, Informative)
"We are focused on achieving high volume applications featuring the unique benefits of HSS directed sound. --"To the Shareholders of American Technology Corp." Business Wire, March 25, 2002
Prior art (Score:3, Funny)
DUPEY DUPE DUPE (Score:5, Informative)
i'm sure this'll come around again in the next few months...
Already in use (Score:4, Interesting)
Frequency change=nonlinearity=high levels (Score:5, Interesting)
(http://www.dpbsmith.com/)
The thing that I have to wonder about is that this kind of nonlinearity implies fairly high (ultrasonic) sound intensities, and suggests that stuff inside your head is being driven beyond its elastic limit. The big thing that seems to me to be missing from the article is any statement of the ultrasonic sound power level, in decibels, that is being delivered to your head (and the ratio between the actual ultrasonic sound level and the apparent audible sound level).
How does this compare, for example, to the sound levels used for ultrasonic imaging in medicine?
I'm not suggesting that the process is necessarily dangerous, but it isn't obvious that it's intrinsically safe, either. It's one thing to be subjected to high-power ultrasound a few dozen times during your lifetime for the purpose of preserving your health. It's quite another to be subjected to it day in and day out, for your convenience in listening to music, or for some advertiser's convenience in interrupting your train of thought.
Prior Art (Score:5, Informative)
Tab books published instructions [amazon.com] how to build a device that does exactly this decades ago... TAB!
Yeah, I know the cover looks ridiculous... I bought it when I was a teen and still have it - neat projects inside and better written than the cover would indicate.
neither one (Score:4, Interesting)
(http://www.freshraisins.com/)
This focusing can be done with more than just sound waves however, and the first applications are in medicine [sciencedaily.com], however, it does apply to sound as well.
The basic idea is that if you create a sound from some source location, and record all of the noise at another location, then play this noise signal backwards from the recorded location the sound will reappear in the one spot from which it was originally played. An analogy is that if you take a pool ball, put it right in front of a pocket, and then bounce it outwards really hard, letting it bounce against the walls multiple times, but noting the exact location of the last bounce of the ball, then if you reshot the ball at the exact spot where you last saw it bounce, it would go back in the whole.
Cone of Silence (Score:3, Funny)
*sees peoples mouths moving. realizes they are talking to him.
"I'm in the cone of silence, you insensitive clods!"
For all you South Park fans (Score:3, Funny)
These things can be dangerous (Score:3, Interesting)
In Theory... (Score:5, Informative)
That's the idea, but in reality it works a tad different. Wherever the beam hits sort of becomes the apparent source of the sound. So if you aim it at someone, they'll hear it quite clearly - more so than everyone else - but the sound will now appear to be coming from them. Quieter, but still apparent.
I've got 2 of the HSS units right here, and though they're super-cool for messing with people, (See other posts) they've got some drawbacks.
1) There's no bass, treble only.
2) The units we have come with a rather noisy cooling fan.
3) They clip quite easily - you have to watch your volume levels.
4) They're not terribly reliable. I've seen them in a few labs I've worked in or with, and we all seem to have the same issues.
Overall a cool product, especially for the gee-whiz factory, but certainly not ready for practical use just yet.
Re:Can I smell something ? (Score:5, Informative)
(http://www.rollbots.com/)
I think the reason you probably haven't seen it yet is that there aren't many finished products made yet, and part of that might have to do with the fact that lots of local bylaws seem concerned with this kind of thing (they liken it to talking on cell phones while driving).
It won't be long before this is everywhere. I think the tech is just slightly outpacing the market right now.
Re:Can I smell something ? (Score:4, Funny)
God: (standing on a chair behind Noah, he rings a bell once) NOAH. ... Where are ya? What do ya want? I've been good. ... What's an ark? ... What's a cubit? ... Who is this really? What's going on? How come you want me to
do all these weird things? ... Am I on Candid Camera? How are you gonna do it? ... Listen, do this and you'll save water. Let it rain for forty
days and forty nights and wait for the sewers to back up.
Noah: (Looks up) Is someone calling me? (Shrugs and goes back to his work)
God: (Ding) NOAH!!
Noah: Who is that?
God: It's the Lord, Noah.
Noah: Right
God: I want you to build an ark.
Noah: Right
God: Get some wood and build it 300 cubits by 80 cubits by 40 cubits.
Noah: Right
God: Well never mind. Don't worry about that right now. After you build the ark, I want you to go out into the world and collect all the animals of the world, two by two, male and female, and put them into the ark.
Noah: Right
God: I'm going to destroy the world.
Noah: Right
God: I'm going to make it rain for a thousand days and drown them right out.
Noah: Right
God: Right...
Narrator: So Noah began to build the ark. Of course his neighbors were not too happy about it. Can you imagine leaving for the office at 7 AM and seeing an ark?
Neighbor: (enters whistling, with brief case) Hey! You over there.
Noah: What do you want?
Neighbor: What is this thing?
Noah: It's an ark.
Neighbor: Uh huh, well you want to get it out of my driveway? I've gotta get to work. Hey listen, what's this thing for anyway?
Noah: I can't tell you, ha ha ha.
Neighbor: Can't you even give me a little hint?
Noah: You want a hint?
Neighbor: Yes, please.
Noah: Well, how long can you tread water? Ha ha ha
Neighbor: There's one in every neighborhood. (Shakes head and leaves)
Narrator: Well Noah finally got the ark built. Then he had the task of gathering all the animals two by two.
Noah: Hey, anybody know how to tell the difference between a male and a female mosquito? (Looking in a box) I told your rabbits before, only two! (He puts box in boat) Whew, finally the last two animals are on board. Let's get this thing closed up before God asks me to do something else. I'm six hundred years old. I am getting too old for this sort of thing.
God: Noah!
Noah: I knew it. What do you want now?
God: You're going to have to take one of those hippos off and get another one.
Noah: Why?
God: 'Cause you got two males. You need a female.
Noah: I'm too tired to bring anything else on board. You change one of them.
God: Come on, you know I don't work like that.
Noah: But I'm sick and tired of this. I've been working all day everyday like crazy for months now, dawn to dusk. I'm tired of this.
God: Noah
Noah: Yeah?
God: how long can you tread water? Ha ha ha
Noah: Yeah, well I got news for you. You keep talking about this flood and I haven't seen a drop of rain. Meanwhile, the whole neighborhood is making fun of me. I told one of my friends I'd been talking to the Lord and he laughed so hard he wet his pants. Do you know I'm the only guy in town with an ark in his yard? People are picketing and calling the heath department, strangers walk up to me and say "How's it going, Tarzan?" I am sick and tired of all of this, you let me get a pregnant elephant . . . Do you give me an instruction book? . . . No!!! Here I am standing under the elephant and brrrrrrrrump! Right on top of me! I'm telling you, I've had enough. You're supposed to see all and know all, well have you seen the bottom of that ark? Who's going to clean up that mess? Not me, I tell you. I quit. I'm tired of this. I'm going to let the animals out and burn that ark down. I can't believe you made me do all this . . . (God takes a watering can and begins to pour w
Re:Can I smell something ? (Score:5, Informative)
(http://www.toombeola.com/)
Re:Can I smell something ? (Score:3, Interesting)
(Last Journal: Wednesday April 02 2003, @08:43AM)
Re:Can I smell something ? (Score:4, Insightful)
(http://slashdot.org/)
As I tried to keep up with who was developing what with the tech (it's been licensed over and over, but nobody's ever built anything commercially available) I got more and more depressed with the whole thing. And I learned an important life lesson... until you can click "Buy Now," (and sometimes not even then) it may as well not exist unless you intend to build your own from a copy of the patent. I try to just ignore announcements like "Hypersonic Sound" now.