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Directed Sound
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!"
Actually it isnt vaporware, they showed a working version of it on TechTV a while ago. So its not a matter of it existing, but a matter of when companys are going to use it.
It would be simple to defeat though. The effect relies on heterodyning a signal (mixing HF to produce an intermodulation effect) so broadcasting white noise above the range of hearing should drown the wanted signal nicely - just like interference on an AM radio. Say a small device located near the billboard - or two piezo drivers on the outside of headphones, heck you could build it into your cellphone hands-free kit.
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?
While I agree that this would suck, it could have benefits. Anything used for spamming receives a *LOT* of funding...this sort of technology could mature very, very quickly because of its revenue stream, leading to other, more practical uses. Remember, if it weren't for pr0n, we would prolly still be surfing on 28.8 modems, not broadband.
--trb
True. I bet it'd be more cost-effective in places like museums where quiet is desired, but some people might like to hear recordings on the exhibits.
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The sound could well appear back where it was originally played (though I have my doubts since its impossible to measure all effects of the sound everywhere) to a person standing there but other people standing nearby will still hear sound but it'll just be a jumble of noise. So thats hardly directed sound is it?
Not cone of silence!
Cone of marketing.
Cone of limited time only specials!
Cone of "welcome passerby, if you look directly to your left...."
Cone of "your girlfriend can't hear this, so listen closely..."
Just so this post isn't totally lame, here is a potential useful application.
Directed sound technology might be useful in applications where you want to give someone audible feedback or instructions, where someone normally would have one of those tiny earpieces. Cyrano de Bergerac. (See the commedy with Steve Martin called Roxane.) One man is secretly prompting another man with what to say to lure a potential girlfriend.
Now you could send someone secret audible messages so that they say intelligent things instead of their own original thoughts. Useful for political campaigns where public figure is near to public crowd, near enough for them to notice any earpiece electronics he might be wearing.
The price of freedom is eternal litigation.
Yeah, this particular little invention is what really drove the concept of "vapourware" home for me. I read about it first while I was in college, back in *1998*. I followed it excitedly, because at the time it was touted as a lightweight, low-power, flat-frequency-response speaker system. The directionality was just a side effect. Turns out it's not all it's cracked up to be in the audio quality department, but hey... that side effect is still there six years later, so let's capitalize on that instead!
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.
Seriously, marketers will be in heaven, able to target ads at passerbys.
Targeting specific people in a crowd doesn't make any sense advertising-wise or cost-wise, especially if it costs more than broadcasting a message to the entire crowd.
If marketers had any interest whatsoever in this type of advertising, there would be bullhorns in public places already constantly exhorting everyone to Drink Coke or Join The Army or whatever. As it stands, only political candidates and ice cream trucks are willing to do this.