The document discusses audio spotlighting, a technology that utilizes ultrasonic energy to produce focused sound beams similar to light beams, allowing sound to be directed to specific listeners without disturbing others. It covers the device's theory, components, advantages, and applications across various fields including retail, public safety, and entertainment. The conclusion emphasizes the potential of audio spotlighting to revolutionize sound transmission, enabling users to control sound directionality and enhance auditory experiences.

1. A seminar on
AUDIO SPOTLIGHTING
Presented by
RAKESH B
(1BY06EC044)
Under the guidance of Prof. ANIL KUMAR D

2. CONTENTS
1. INTRODUCTION
2. THEORY
3. WORKING
4. COMPONENTS AND BLOCK DIAGRAM
5. TYPES OF MODES
6. ADVANTAGES
7. APPLICATIONS
8. CONCLUSION
9. BIBLIOGRAPHY

3.  Audio Spotlighting was invented by Dr. F. Joseph
Pompei.
 Production of focused beams of sound.
 Uses ultrasonic energy to create narrow beams of
sound.
 Non-linearity of the air aid the device for its
working.
 Device used: Parametric Loudspeaker or Array.
INTRODUCTION

4.  Audio spot lighting is a technology that creates
focused beams of sound similar to light beams
coming out of a flashlight.
 By ‘shining’ sound to one location, specific
listeners can be targeted with sound without
others nearby hearing it.
 The Audio Spotlight uses ultrasonic energy to
create extremely narrow beams of sound that
behave like beams of light.
THEORY

5.  Ultrasonic sound has very small wavelength in the
millimeter range and lies beyond the threshold of
human hearing.
Low Beam Angle is required to focus the sound.
Smaller the wavelength, lesser the beam angle.
Another way to focus sound is to increase aperture
size of speakers(10m diameter for 20Hz) practically
difficult.
Cont…

6. AUDIO SPOTLIGHT CREATES FOCUSED BEAM OF
SOUND UNLIKE CONVENTIONAL LOUD SPEAKERS …
Audio spotlight looks like a disc-shaped loudspeaker,
trailing a wire, with a small laser guide-beam mounted
in the middle.
Cont…

7. WORKING
Audio Spotlighting Emitter
(21k to 28k Hz)
(Speech or music)

8. Cont…
 Frequency modulated signal travels through air, non-
linearity property of air comes into action which slightly
changes the sound wave.
 Due to change in a sound wave(ultrasonic), new sounds are
formed within the wave.
 New sound signal corresponds to the original information
signal in the range 20Hz to 20kHz.
 Inherent non-linearity of the air works as a
de-modulator and thus de-modulated sounds impinge on our
eardrums. We can hear those sounds.
 The ultrasonic envelope acts as an airborne speaker.

9. Directivity

10. DISPERSION OF SOUND BEAM

11. COMPONENTS
 Power supply
 Frequency oscillator
 Modulator
 Audio signal processor
 Microcontroller
 Ultrasonic amplifier
 Transducer

12. BLOCK DIAGRAM OF AN AUDIO
SPOTLIGHTING SYSTEM

13. MODES OF LISTENING
 Direct Mode
 Projected Mode

14. CONVENTIONAL SPEAKERS AUDIO SPOTLIGHTING
COMPARISON BETWEEN CONVENTIONAL
SPEAKERS & AUDIO SPOTLIGHTING

15. ADVANTAGES
1.Can focus sound only at the place you want.
2.Ultrasonic emitter devices are thin and flat
and do not require a mounting cabinet.
3.Focused sound travels much faster in a
straight line than conventional loudspeakers.
4.Dispersion can be controlled - very narrow or
wider to cover more listening area.

16. 5. Highly cost effective.
6. Low maintenance and longer life span.
7. Requires low power.
8. No lag in reproducing the sound.
Cont…

17. APPLICATIONS
1. Automobiles: Beam alert signals can be directly
propagated from an announcement device in the
dashboard to the driver.
2. Retail sales: Provide targeted advertising directly at the
point of purchase.
3. Safety officials: Portable audio spotlighting devices for
communicating with a specific person in a crowd of
people.

18. 4. Public announcement: Highly focused announcement in
noisy environments such subways, airports, amusement
parks, traffic intersections etc.
5. Emergency rescue: Rescuers can communicate with
endangered people far from reach.
6. Entertainment system: In home theatre system rear
speakers can be eliminated by the implementation of
audio spotlighting and the properties of sound can be
improved.
Cont…

19. 7. Museums: Audio spotlight can be used to describe about
a particular object only to a person standing in front of it.
8. Military applications: Ship-to-ship communication and
shipboard announcements.
9. Audio/Video conferring: Project the audio from a
conference in 4 different languages, from a single central
device without the need for headphones.
10. Sound bullets: Jack the sound level 50 times the human
threshold of pain, and an offshoot of audio spotlighting
sound technology becomes a non-lethal weapon.
Cont…

20. FUTURE OF AUDIO SPOTLIGHTING
Audio spotlighting system holds the promise of
replacing conventional speakers.
It allows the user to control the direction of
propagation of sound.
The audio spotlight will force people to think
their relationship with sound. Audio spotlighting
really “put sound where you want”.

21. CONCLUSION
Audio spotlighting is really going to make a revolution
in sound transmission and the user can decide the
path in which audio signal should propagate.
 Audio spotlighting system is going to shape the
future of sound and will serve our ears with magical
experience.
So we can conclude- Audio Spotlighting really “put
sound where you want it” and will be
“A REAL BOON TO THE FUTURE.”

22. BIBLIOGRAPHY
 F. Joseph Pompei: The use of airborne
ultrasonics for generating audible sound beams.
 www.silentsound.co.za – Silent sound.
 www.wikipedia.org - Sound from Ultrasound.
 www.howstuffworks.com
 www.holosonics.com
 Electronics For You – Vol. 40 January 2008.

23. THANK YOU 