Hypersonic Sound by American Technology CORPORATION (also known as HSS)

Comparisons with other Directional Sound Relevant Technologies such as sound domes and sound arrays

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Technical advice and consulting for Audio Spotlight and Hypersonic Sound applications!

Audio Spotlight and Hypersonic Sound (HSS) introduction

Imagine ­ projecting sound in a narrow beam, much like the light from a spotlight! In the past we were limited by sound invading all of the space surrounding the loudspeaker or sound source. Not anymore! With the Audio Spotlight or Hypersonic Sound systems, you can put sound wherever you want. Keep the analogy of a spotlight in mind. With a spotlight, when you step into the beam of light, you are clearly illuminated by the light. When you step out of the beam, you are lit only by the background light. Now imagine a beam of sound! You can’t see the beam, but when you step into it, you can hear the sound or narration inside! Step back out of the beam and the sound is gone!

Imagine the ability to put sound wherever you want! We can now contain sound in a beam using an Audio Spotlight or Hypersonic Sound! Stepping into the directional sound beam is like putting on a set of virtual headphones. Imagine, you can now have several different soundtracks or musical styles co-exist in one small space, heard only by those who should.

We can deliver a specific message to a certain group or individual.
We can create a distinct musical atmosphere within a very small area.

This ability is possible using the Audio Spotlight or Hypersonic Sound directed audio sound systems.

How do these systems work?
The directivity (narrowness) of any wave producing source depends on the size of the source, compared to the wavelengths it generates. Audible sound has wavelengths ranging from a few inches to several feet, and because these wavelengths are comparable to the size of most loudspeakers, sound generally propagates omnidirectionally. Only by creating a sound source much larger than the wavelengths it's producing is it possible to create a narrow beam using a standard style loudspeaker and amplifier.
Clearly, having loudspeakers twenty meters wide is not very useful. So to make a narrow beam of sound from a small acoustic source, we instead generate only ultrasound.

The ultrasound, whose wavelengths are only a few millimetres long, are much smaller than the source, and consequently tend to travel in a straight line, much like the beam of light from a flashlight. Of course, this ultrasound, which contains frequencies far outside our range of hearing, is completely inaudible. But as the ultrasonic beam travels through the air, the inherent properties of the air cause the ultrasound to distort (change shape) in a predictable way. This distortion gives rise to frequency components in the audible bandwidth, which can be accurately predicted, and therefore precisely controlled. By generating the correct ultrasonic signal, we can create, within the air itself, essentially any sound desired.

Note that the source of sound is not the transducer or physical device you see, but the invisible beam of ultrasound, which can be many meters long. This new sound source, while invisible, is very large compared to the audio wavelengths it's generating. So the resulting audio is now extremely directional, just like a beam of light.

For years scientists have used transducers for everything from medical ultrasound imaging to fishfinders (for other transducer applications click here), and now they have developed a practical way for us to use a directional "beam" of sound to communicate critical information to small groups or individuals within a crowd, using either the Audio Spotlight, or Hypersonic Sound system.

Audio Spotlights by Exhibit and Display Consultants • 417 Atwells Avenue •Providence RI 02909 • 401-273-5372
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