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Audio Spotlighting. Anoob Hamza Mohammed | 1HM03EC006 | VIII ECE | H.M.S.I.T, Tumkur. Contents :. Introduction How does It work? History The Inventor Why audio spotlight? The Audio spotlighting System Technical Overview. Advantages Disadvantages Limitations Applications
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Audio Spotlighting Anoob Hamza Mohammed | 1HM03EC006 | VIII ECE | H.M.S.I.T, Tumkur
Contents : • Introduction • How does It work? • History • The Inventor • Why audio spotlight? • The Audio spotlighting System • Technical Overview Advantages Disadvantages Limitations Applications Conclusion Bibliography
Introduction : What is Audio Spotlight ? Audio Spotlighting is a very recent technology that focuses a beam of sound to the intended audience. The Audio Spotlight uses ultrasonic energy to create extremely narrow beams of sound.
Demonstration : Now Let Us All Watch A Video To Understand The Effectiveness Of Audio Spotlight System. This video is being demonstrated by Dr. F. Joseph Pompei .
Conventional Loudspeaker & Audio Spotlighting Ultrasonic Emitter
Range Of Hearing : The human ear is sensitive to frequencies from 20Hz to 20KHz. No single loud speaker element can operate efficiently over this range of frequencies. Hence the speaker manufacturers carve the audio spectrum into smaller sections, which require multiple transducers.
How does it work? Audio spotlighting exploits the property of non-linearity of air. Sound may be projected to just about any desired point in the listening environment.
Non-Linearity of Air : A device known as a parametric array employs the non-linearity of the air to create audible by-products from inaudible ultrasound. The ultrasound column acts as an airborne speaker. As the beam moves through the air, gradual distortion takes place in a predictable way. This gives rise to audible components.
2. Sound And Ultrasonic Wave As Carrier Wave To Build A Hybrid Wave 4. Hybrid Wave Distorts With Air To Produce Audible Sound Wave 5. Finally Audio signals reach the destination. 1. Music & Ultrasound 3. Hybrid Wave
History : The US govt. worked on creating Ultrasonic sound for using it as a weapon for many years unsuccessfully. In 2000, Dr. F. Josef Pompei PhD (MIT) created successfully a device which emits ultrasonic sound which he called Audio Spotlight. In 2002 Elwood Norris, owner of American technology corporation developed a similar technology which he called Hypersonic Sound.
The Inventor: Dr. Joseph Pompei Inventor of audio spotlight ™ .
Why Audio Spotlight? The ability of Audio spotlight to direct or focus sound into a tight beam, which no other audio reproduction device available today provides. Audio spotlight creates ultrasonic sound that travels in a straight line rather than spreading out like lower frequency sound. The opportunities for applying this characteristic to the reproduction of sound are limitless.
The Audio Spotlighting System 3 Major Components • A Thin, Circular Transducer Array • A Signal Processor • An Amplifier
Signal processor converts the music from audio source to a highly complex ultrasonic signal. This signal is then amplified and emitted into air by the transducer.
Its characteristics allow it to perform in ways conventional loudspeakers cannot • Its characteristics allow it to perform in ways conventional loudspeakers cannot Advantages : Focus sound where you want it and no place else. Ultrasonic emitter devices are thin and flat and do not require a mounting cabinet. The focused or directed sound travels much farther in a straight line than conventional loudspeakers
Its characteristics allow it to perform in ways conventional loudspeakers cannot • Its characteristics allow it to perform in ways conventional loudspeakers cannot Applications : Museums Automobiles Audio/video conferencing Paging systems Military applications Helpful for blind people Sound bullets Virtual home theatre Safety officials
Its characteristics allow it to perform in ways conventional loudspeakers cannot • Its characteristics allow it to perform in ways conventional loudspeakers cannot Conclusion : Besides consumer electronics, the entertainment industry is expected to be influenced by this development. Virtual reality, in large-scale applications, has been brought another step closer. Audio spotlighting technology can replace the bulkier, inefficient speakers and provide far better results than we ever heard. With Audio spotlighting technology , hearing aids may produce the entire audio spectrum and may also shrink in size.
Bibliography: M.Yonema and J.Humoto. The audio spotlight: An application of nonlinear interaction of sound waves to a new type of loudspeaker design, J. Acoustical Society of America, vol. 73, no.5, pages 1532-1536, May 1983 Holosonics.com. 2002. (July 21, 2008) http://www.holosonics.com/technology.html Audiospotlights.com. 2005. http://www.audiospotlights.com/index.html www.howstuffworks.com
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