Hypersonic What?

tangerine

tangerine

grumpy bastard
Has anyone got any info on Hypersonic sound? I know it has something to do with being able to direct sound like you can a beam of light and it relies on the non linearity of air molecules (what ever that means), If anyone can fill me in on this supposed new sound science I'd be grateful...........cheers. :)
 
i've heard something about whatever-it-is your talking about
(although the tearm hypersonic sound seems a bit.... well.... stupid)

some kinda technology whare they can aim sound over long distances
(think 100 yards) with pin-point accuracy.

think-some asshole you can't see halfway across a park literally beaming a f'n add directly into your right ear that noone else can hear.
untill he turns it on them, welcome to the future. :mad:

that's all i know and it may be completely innaccurate!!!!!!
 
giraffe said:
i've heard something about whatever-it-is your talking about
(although the tearm hypersonic sound seems a bit.... well.... stupid)

some kinda technology whare they can aim sound over long distances
(think 100 yards) with pin-point accuracy.

think-some asshole you can't see halfway across a park literally beaming a f'n add directly into your right ear that noone else can hear.
untill he turns it on them, welcome to the future. :mad:

that's all i know and it may be completely innaccurate!!!!!!
Click to expand...

I saw a demonstration on TV and it looked wild. You can bounce the sound off hard surfaces but as soon as something like a soft cushion is put in front of the beam the sound is absorbed. They reckoned you could use it for surround sound from your tv and not annoy the neighbors.
 
I've just found this............................HyperSonic Sound

What is HSS?
HyperSonic Sound Technology is simply the most revolutionary sound reproduction system of this century. Not since the development of the "cone" loudspeaker more than 75 years ago has any technology provided such significant departure from conventional loudspeakers and such a remarkable new approach to the reproduction of sound.

How does it work?
The basic operating principle of HSS uses a property of air known as "non-linearity". A normal sound wave (like someone talking) is a small pressure wave that travels through the air. As the pressure goes up and down, the "non-linear" nature of the air itself causes the sound wave to be changed slightly. If you change a sound wave, new sounds (frequencies) are formed within the wave. Therefore, if we know how the air affects the sound waves, we can predict exactly what new frequencies (sounds) will be added into the sound wave by the air itself. An ultrasonic (beyond the range of human hearing) sound wave can be sent into the air with sufficient volume to cause the air to create these new frequencies. Since we cannot hear the ultrasonic sound, we only hear the new sounds that are formed by the non-linear action of the air.

The HSS System
A HyperSonic Sound system consists of an audio program source such as a CD player or microphone, an HSS signal processor, and an ultrasonic emitter or transducer that is powered by an ultrasonic amplifier.

The music or voice from the audio source is converted to a highly complex ultrasonic signal by the signal processor before being amplified and emitted into the air by the transducer (emitter). Since the ultrasonic energy is highly directional, it forms a virtual column of sound directly in front of the emitter, much like the light from a flashlight. All along that column of ultrasonic sound, the air is creating new sounds (the sound that we originally converted to an ultrasonic wave). Since the sound that we hear is created right in the column of ultrasonic energy, it does not spread in all directions like the sound from a conventional loudspeaker, instead it stays locked tightly inside the column of ultrasonic energy. In order to hear the sound, your ears must be in line with the column of ultrasound, or, you can hear the sound after it reflects off a hard surface. For example, if you point the ultrasonic emitter toward a wall, you will only hear the audible sound after it has reflected off the wall. This is similar to shining a flashlight at a wall in a dark room. You do not see the light from the flashlight, you only see the spot of light on the wall. HSS works the same way, except instead of seeing the spot of light on the wall, you hear the "spot" of sound reflected from the wall. For stereo, a separate ultrasonic emitter is required for each channel of audio, one for the left channel and one for the right channel.

Why HSS?
There are many reasons. The first and most important is the ability to direct or focus sound into a tight beam, similar to the beam of light from the flashlight described above. No other audio reproduction device available today provides this unique ability. The opportunities for applying this characteristic to the reproduction of sound are limitless. Think about the ability in a museum to direct the narration about a specific display only to the people standing directly in front of it. How about the potential to reflect the rear channels of your surround TV from the rear wall of your living room, by focusing HSS speakers mounted on the TV itself - no rear speakers, no rear wiring. Think about the ability to focus sound into a crowd of people on a football field and talk only to a selected few.

The following contains a brief list of other uses made possible by HSS:

Automobiles - HSS announcement device in the dash to "beam" alert signals directly to the driver
Audio/Video Conferencing - project the audio from a conference in four different languages, from a single central device, without the need for headphones
Paging Systems - direct the announcement to the specific area of interest
Retail Sales - provide targeted advertising directly at the point of purchase
Drive Through Ordering - intelligible communications directly with an automobile driver without bothering the surrounding neighbors
Safety Officials - portable "bull horn" type device for communicating with a specific person in a crowd of people
Military Applications - ship to ship communications, ship-board announcements
 
i posted a thread a little while back about it.
basically, it's a really cool concept that a lot of advertising companies are trying to start using more of. I know Coca Cola has tried it out in some of their coke machines and Japan is using it more and more.

Some downsides is that it only works with line of sight and the speaker's frequency response isn't that great. These speakers are also only available for industrial use and not for consumers.
 
AarrrwooOOoooo!

tangerine said:
An ultrasonic (beyond the range of human hearing) sound wave can be sent into the air with sufficient volume to cause the air to create these new frequencies. Since we cannot hear the ultrasonic sound, we only hear the new sounds that are formed by the non-linear action of the air.
Click to expand...
Oh, yeah, the neighborhood dogs will love that one! ;)

G.
 
tangerine said:
I've just found this............................HyperSonic Sound

What is HSS?
HyperSonic Sound Technology is simply the most revolutionary sound reproduction system of this century. Not since the development of the "cone" loudspeaker more than 75 years ago has any technology provided such significant departure from conventional loudspeakers and such a remarkable new approach to the reproduction of sound.

How does it work?
The basic operating principle of HSS uses a property of air known as "non-linearity". A normal sound wave (like someone talking) is a small pressure wave that travels through the air. As the pressure goes up and down, the "non-linear" nature of the air itself causes the sound wave to be changed slightly. If you change a sound wave, new sounds (frequencies) are formed within the wave. Therefore, if we know how the air affects the sound waves, we can predict exactly what new frequencies (sounds) will be added into the sound wave by the air itself. An ultrasonic (beyond the range of human hearing) sound wave can be sent into the air with sufficient volume to cause the air to create these new frequencies. Since we cannot hear the ultrasonic sound, we only hear the new sounds that are formed by the non-linear action of the air.

The HSS System
A HyperSonic Sound system consists of an audio program source such as a CD player or microphone, an HSS signal processor, and an ultrasonic emitter or transducer that is powered by an ultrasonic amplifier.

The music or voice from the audio source is converted to a highly complex ultrasonic signal by the signal processor before being amplified and emitted into the air by the transducer (emitter). Since the ultrasonic energy is highly directional, it forms a virtual column of sound directly in front of the emitter, much like the light from a flashlight. All along that column of ultrasonic sound, the air is creating new sounds (the sound that we originally converted to an ultrasonic wave). Since the sound that we hear is created right in the column of ultrasonic energy, it does not spread in all directions like the sound from a conventional loudspeaker, instead it stays locked tightly inside the column of ultrasonic energy. In order to hear the sound, your ears must be in line with the column of ultrasound, or, you can hear the sound after it reflects off a hard surface. For example, if you point the ultrasonic emitter toward a wall, you will only hear the audible sound after it has reflected off the wall. This is similar to shining a flashlight at a wall in a dark room. You do not see the light from the flashlight, you only see the spot of light on the wall. HSS works the same way, except instead of seeing the spot of light on the wall, you hear the "spot" of sound reflected from the wall. For stereo, a separate ultrasonic emitter is required for each channel of audio, one for the left channel and one for the right channel.

Why HSS?
There are many reasons. The first and most important is the ability to direct or focus sound into a tight beam, similar to the beam of light from the flashlight described above. No other audio reproduction device available today provides this unique ability. The opportunities for applying this characteristic to the reproduction of sound are limitless. Think about the ability in a museum to direct the narration about a specific display only to the people standing directly in front of it. How about the potential to reflect the rear channels of your surround TV from the rear wall of your living room, by focusing HSS speakers mounted on the TV itself - no rear speakers, no rear wiring. Think about the ability to focus sound into a crowd of people on a football field and talk only to a selected few.

The following contains a brief list of other uses made possible by HSS:

Automobiles - HSS announcement device in the dash to "beam" alert signals directly to the driver
Audio/Video Conferencing - project the audio from a conference in four different languages, from a single central device, without the need for headphones
Paging Systems - direct the announcement to the specific area of interest
Retail Sales - provide targeted advertising directly at the point of purchase
Drive Through Ordering - intelligible communications directly with an automobile driver without bothering the surrounding neighbors
Safety Officials - portable "bull horn" type device for communicating with a specific person in a crowd of people
Military Applications - ship to ship communications, ship-board announcements
Click to expand...


Think about it in the great sceme of things, Riot police could use it, before you know it you've been hit by the brown note and your running like you've shit yourself, because you have shit yourself :eek: .
 
Schubert said:
Think about it in the great sceme of things, Riot police could use it, before you know it you've been hit by the brown note and your running like you've shit yourself, because you have shit yourself :eek: .
Click to expand...

lol, it's a good concept, but not plausible with this idea. again, the speaker's frequency response is terrible and the brown note requires a lot more than just a single speaker. The brown note is 4Hz at 140dB and requires huge subwoofers that are generally made of kevlar. and low frequencies aren't directional.
 
Last edited:
bennychico11 said:
lol, it's a good concept, but not plausible with this concept. again, the speaker's frequency response is terrible and the brown note requires a lot more than just a single speaker. The brown note is 4Hz at 140dB and requires huge subwoofers that are generally made of kevlar. and low frequencies aren't directional.
Click to expand...


I thought it was somewhere between 6 and 7 Hz. Anyway that's immaterial. The fact that they've managed to do what was previously thought of as the impossible makes it all the more possible. If you can see where I'm coming from.
 
bennychico11 said:
it wouldn't be heard by dogs unless aimed at them. it's a concentrated beam of sound that is directional.
Click to expand...
Until it hits a solid surface like a wall or window, after which it will radiate off in just about every direction possible.

G.
 
SouthSIDE Glen said:
Until it hits a solid surface like a wall or window, after which it will radiate off in just about every direction possible.

G.
Click to expand...

so they claim. but what makes it able to only be heard by one person if you aim it at them? Wouldn't reflections off a person's head allow anyone to hear it?

also...again, the frequency response of the speaker is not that great...so it's ability to replicate ultrasonic freq. would probably be poor. the frequency is probably created and used as a carrier wave, but once it hits something it probably dissipates.
 
bennychico11 said:
so they claim. but what makes it able to only be heard by one person if you aim it at them? Wouldn't reflections off a person's head allow anyone to hear it?

also...again, the frequency response of the speaker is not that great...so it's ability to replicate ultrasonic freq. would probably be poor. the frequency is probably created and used as a carrier wave, but once it hits something it probably dissipates.
Click to expand...
Well, first let me throw out the caveat that I am no expert on just how this process works in any detail, and I could be wrong. I'm only going on what basic sound and general physics theory I do know. But I'll give it a shot and see if I can get even close to the truth. ;)

What I *think* is happening is that they are somehow directing an untrasonic wavefront that is highly directional, coherent wave (somewhat like an audio version of a laser or maser.) I'm not sure just how this is accomplished (standing waves or solitons?), but I'll take that as a given for this thread. What is audible to the human ear (the sonic and not the ultrasonic) is an "artifact" caused by non-linear harmonic disturbances to the air caused by the ultrasonic wavefront. In other words, what we are hearing is not the ultrasound itself - which is beyond our range of hearing - but rather the audible side effects caused by the ultrasoinc wave. Because these are side effects caused by nearly coherent and therefore small cross-section waves of air pressure, they just do not have the "oomph" to create an audible sound field for very far off the axis of the ultrasonic wave. Thus the highly-directional nature of the audible sound.

I think that when they refer to limited frequency response they may be actually referring to the furquency range of the audible side effects; I would imagine the non-linear functions for creating an 20-20K side effect would probably require real-time resource upwards of a dedicated G5 processor to model, if it's even physically feasable.

Anyway, given the above reasoning that the coherent wavefront is needed to create the desired audible effect, it is only as long as this coherent wavefront stays intact that the effect is created. Once the wavefront hits a reflective surface, the coherency is broken and the audible sound effect is no longer generated. That, however does not necessarily mean that the ultrasonic sounds just disappear, it just means that they lose their coherency. Think of it like light. If you shine a laser on a wall, the laser light loses it's coherency and singular direction, but it does not disappear. This is seen (and proved) by the fact that you can see the red dot on the wall from any point in the room; the light is scattered back in all directions so all can see it.

Unless you have a surface that is a perfect "mirror" for the ultrasound waves in this audio process and reflects the standing ultrasonic waves back at the exact same angle of incidence as the originals, the coherency will be lost and the ultasounds will be reflected back in a spread pattern like the laser light would be. But because the sound is no longer "beamed", so to speak, reflected sounds do not cause the audible side effects and cannot be heard.

But the dispursions should, for the most part, remain in the same ultrasonic frequency range. If this is within the range of animals like dogs - and to be honest, I'm not even sure the original ultrasonic beams are in that range - that means there is a potential for them to hear the reflections even if they are off-axis from the original beam.

Does that make any sense?

G.
 
Last edited:
Excellent explanation.


Before I read about this hypersonic stuff, I didn't know that air had a "non-linear" property. It basically sounds like they're just abusing the air's natural "Nyquist" (I mean this in a loose sense) to create the directional effect... very interesting.
 
no, i understand how the sound is carried...i'm just saying if beam of sound is able to reflect off a door or wall and spread so it can be heard around the room...then how is it that when it hits a persons head that it's pointed at that it still is only heard by that one person?

also, by poor frequency response I meant the speaker itself is. on their website they have the specs of it and it looks like it gets to around 15kHz.
 
Whod'a thunk it

bleyrad,

I'm with you; I'm not sure just how they get the air to act like that, expecially when you consider constant temperature, barometric pressure and humidity changes and such. Nor had I even considered it.

But now that I think of it, if it can happen in open water (soliton waves have been known to travel in a straight line for thousands of miles before breaking up), why not in open air? The real trick, like Benny said, is think of the idea to modulate it in such a way to work as advertised.

I guess that's why these guys will be driving around in Bentleys in a couple of years while I'm still trying to get a decent sound out of my SM57. :D

G.
 
Benny,

If my theory is correct, the reason you can aim it at a person's head and he can hear it is because he's close enough to the coherent ultrasonic beam to hear the desired audible side effects. The reason others can't hear it from the reflection off his head is because that reflection is no longer coherent, therefore the reflection does not cause the audible side effect.

Again, think of the ultrasound beam as a laser. As long as it remains traveling unimpeded and unaltered, it remains a tight beam and causes the sound you hear. But once that laser hits the wall and is dispersed in all directions, it loses it's coherence, and therefore loses it's ability to create the sound. In your case, replace the wall with the side of someone's head. The end result is the same.

(Especially if it was *my* thick-skulled bonehead of a noggen ;) )

G.
 
SouthSIDE Glen said:
Benny,

If my theory is correct, the reason you can aim it at a person's head and he can hear it is because he's close enough to the coherent ultrasonic beam to hear the desired audible side effects. The reason others can't hear it from the reflection off his head is because that reflection is no longer coherent, therefore the reflection does not cause the audible side effect.

Again, think of the ultrasound beam as a laser. As long as it remains traveling unimpeded and unaltered, it remains a tight beam and causes the sound you hear. But once that laser hits the wall and is dispersed in all directions, it loses it's coherence, and therefore loses it's ability to create the sound. In your case, replace the wall with the side of someone's head. The end result is the same.

(Especially if it was *my* thick-skulled bonehead of a noggen ;) )

G.
Click to expand...

but they ARE saying that if you aim the sound at a wall, it turns the wall into a speaker. the sound hits it, and the beam loses coherence creating the wave of sound at that exact moment so it sounds like it's coming from the wall. I'm just saying if you can do that to a wall, why doesn't it happen to a persons head?
 
bennychico11 said:
but they ARE saying that if you aim the sound at a wall, it turns the wall into a speaker. the sound hits it, and the beam loses coherence creating the wave of sound at that exact moment so it sounds like it's coming from the wall. I'm just saying if you can do that to a wall, why doesn't it happen to a persons head?
Click to expand...
Ah, OK, I misuderstood your question before. My mistake...sorry :rolleyes:

I can't say I know for sure the answer to that one. Just off the top of my head for now, I'm wondering if it maybe has to do with resonance or mass. That is, is it the reflected, incoherant waves themselves that become audible, or is it that the ultrasonics actually cause a sympathetic vibration of the wall itself, literally turning the wall into a kind of transducer?

If it's the former, I'm not sure I have the answer just yet. If it's the latter, perhaps it has to be a surface of certain minimal mass and/or surface area for the resonance to begin.

Just gussing for now...

G.
 
You must log in or register to reply here.
Back
Top