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LASER sound

  [vote for,

If laser lights can be so powerful, because they avoid destructive interfernce, why not sound ? Generate a sound wave of a single frequency sine wave. It should have effetcs similar to LASER, I am guessing. But I could be wrong.
VJW, Feb 18 2012

Long Range Acoustic Hailing http://www.lradx.com/site/
Ultrasonic Hetrodyning [csea, Feb 19 2012]

Two-ring circus http://www.youtube....watch?v=XJk8ijAUCiI
[2 fries shy of a happy meal, Feb 19 2012]

Collimated sound from ultrasound http://en.wikipedia...und_from_ultrasound
A decent overview of the subject [csea, Feb 20 2012]

Travelling air vortex rings as potential communication signals in a cricket http://www.springer...t/h032837831l58825/
Another possibility [csea, Feb 20 2012]


       Sine waves are easy to generate. Audio takes very little energy to create though, and produces very little energy. Sonic cannons are only in the movies.
Psalm_97, Feb 18 2012

       A laser is intense because not so much because all the light is a single frequency, but because all the lightwaves in the beam are synchronized. If you consider a single wave as rising to a maximum and then decreasing to a minimum, well, all the waves in laser light do exactly the same at the same time. In ordinary light some waves rise to a max while others decrease to a minimum, which causes them to partly cancel-out each other, with respect to detecting intensity.   

       For sound waves and this Idea, you would want to duplicate that key aspect of laser light. Note that it could be possible, provided that you plan on using "phonons" moreso than ordinary sound waves. They spread out less as they traverse distance.
Vernon, Feb 18 2012

       I am wondeing if it is possible for waves to be in-phase all the time, if they are of different freuqncies. My understanding was that it is not possible. My guess is that, at some places, they will be inphase and at some places, they will be out-of phase.
VJW, Feb 18 2012

       This is easy enough to test with a bass guitar and a clean, powerful amp. I specify bass because bass notes travel much further, through much thicker material.   

       It is theorized that, before the invention of the ship propeller and the cavitation it caused, a whale's song could travel almost all the way around the world.
Psalm_97, Feb 18 2012

       Phonons, that is a beautiful word.
zeno, Feb 18 2012

       Bass guitar would generate many frequncies. I think simple sine wave oscillator or sound card would be great.
VJW, Feb 18 2012

       If you have an adapter to connect your laptop to the bass amp, yes. Audacity can generate any sine wave and it is free.
Psalm_97, Feb 18 2012

       How fast and how small can vortex rings be? If you could generate them at, say 400Hz, would you not have a targettable sonic gun?
MaxwellBuchanan, Feb 18 2012

       I read something in a Jane's quarterly about micro-vortex rings generated underwater using a focused hydrophone array. I can't link to it (even if I found it) because Jane's online access is sealed tighter than a Swiss bank, but if anyone is interested I'll try to dig up my hard copy.
Alterother, Feb 18 2012

       Please do. As I indicated earlier, I always thought sonic guns to be the province of science fiction and movies. I'd love to be proven wrong in this case.
Psalm_97, Feb 18 2012

       There is a hard upper limit to the intensity of sound, reached when the rarifcation (sp?) of the sound wave approaches vacuum. The advantage of a mono-frequency wave is that it will do so along its length, whereas a multi- frequency wave would only do so where/if the waves all reached peak or valley at the same time.   

       This isn't to say that sonic weapons are impossible, but they're a lot more likely on jupiter than earth.
MechE, Feb 19 2012

       // As I indicated earlier, I always thought sonic guns to be the province of science fiction and movies. //   

       As far as we (the informed public) know, they definitely are. DARPA abandoned researching the offensive applications of sonic projection in the 1970s. This device (which was in proto-development stages at the time of the article) had something to do with spoofing SONAR by altering planar(?) layers in a submarine environment; something like supercavitating decoy countermeasures, but sneakier. I was just contributing to [MaxB]'s query about high-frequency vortex rings. I'll try to dig up the quarterly, but it was from '08 or '09, so if any other Jane's subscribers know the blurb I'm talking about and have more ducks in a row than [The Alterother], feel free to cite it before me.
Alterother, Feb 19 2012

       Typical (link) vortex ring guns seem to be shooting out only one ring at a time. Using sound to do that, at say 400 Hz would mean there 400 rings shot per second.
VJW, Feb 19 2012

       See [link] for a technology that uses a modulated ultrasonic beam to deliver audio in a narrow beam.
csea, Feb 19 2012

       That first link slays me. "I'll huff and I'll puff..."   

       I wonder if there is a way to create a vortex ring which would shrink in diameter as it travelled. It wouldn't be a sound laser but it would pack more whallop if it converged at a target.   

       ...and [link] ya just gotta see.   

       If it were to shrink in diameter, wouldn't it also have to increase in wavelength?
Alterother, Feb 19 2012

       Question: a vortex ring rotates (ie, there is circulation around small-circumference of the torus. It also travels. Is the direction of rotation always coupled to the direction of travel?
MaxwellBuchanan, Feb 19 2012

       Answer: Yes, the inner (smaller radius) travels in the direction of propagation, and the outer (larger radius) is held back by its larger mass.
csea, Feb 20 2012

       Crickets may converse by means of vortex rings [link.]   

       God, this is why I so love the combination of HB and Google!
csea, Feb 20 2012

       I can't find it. Stuffed inna box someplace, no doubt. It was off-topic anyway.
Alterother, Feb 22 2012

       In Science Fiction, lasers already make sound, something akin to 'pew-pew-pew'...
Cedar Park, Feb 22 2012

       The phaser sound in Star Trek: The Next Generation is my all-time favorite weapon sound. But the sound alone didn't do any damage unfortunately...   

       Didn't the hero in "Steel" have a sonic cannon?
Psalm_97, Feb 22 2012

       As does Cyborg of the Teen Titans (though I believe the two characters are loosely based on one another).
Alterother, Feb 22 2012

       No, the original Cyborg was a totally different character. Please don't ask me how I know this, because I read only maybe seven comic books in my whole life, but I remember a half-man, half-robot they called Cyborg. Kind of like Bionic Man.
Psalm_97, Feb 22 2012

       You have to admit, there's a strong resemblance between the two, even in their original forms (pre-TV series). Also, there have been at least three different Cyborgs in various comic book series, and more than one Steel as well. The names are just too generic to only be used once.
Alterother, Feb 22 2012


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