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Directed Sound

Posted by CmdrTaco on 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!"

6 of 251 comments (clear)

  1. More Details... by MisterLawyer · · Score: 5, Informative
    This is more commonly called "HSS", or "HyperSonic Sound", rather than "UltraSonic Sound". The earliest citation to the term "Directed Sound" goes to American Technology Corp.:

    "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

  2. DUPEY DUPE DUPE by justforaday · · Score: 5, Informative

    from here and here.

    i'm sure this'll come around again in the next few months...

    --
    I'll turn into a supernova and burn up everything. Well I'll turn into a black little hole and you'll turn into string.
  3. Re:Can I smell something ? by MrAndrews · · Score: 5, Informative

    I don't know what the official definition of vapourware is, but I have seen this in use from rooftops at MIT (it's fun to see the reaction of people as they try and figure out if anyone else heard that voice), and am helping in the development of a line of products that use these speakers as a key component.

    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.

    --
    The world's only surviving livewriter.
  4. Re:Can I smell something ? by PaschalNee · · Score: 4, Informative

    Based on this it seemed to be pretty far advanced (and that was two years ago). Granted I've yet to see it being used commercially.

  5. Prior Art by Kevin+Burtch · · Score: 4, Informative


    Tab books published instructions 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.

    --
    - Preferences: Solaris 10 (servers), Ubuntu (desktops), Solaris 11 (personal servers) -
  6. In Theory... by mistermund · · Score: 4, Informative

    You could be standing right next to someone and they would hear nothing.

    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.