AUDIO SPOTLIGHTING

PRESENTED BY: NAMRATA

MAURYA EI-4rth Year

0712232035

INTODUCTION

Audio spot lighting produces audio beam like a flash light.

Make use of interference from ultrasonic waves.

Potentially great dynamic range(better than speaker cones).

THEORY Audio spotlighting is a technology that

creates focused beam of sound similar to light beam coming out of a flash light.

By shining sound to one location, specific listeners can be targated with sound without others nearby hearing it.

The audio spotlighting & hyper sound technology uses ultrasonic energy to create extremely beams of sound thaht.t behave like beams of light.

Technology It is developed by

“American tecnology corporation” uses Ultrasonic energy to create extremely narrow beam of sound that behave like beam of light .

Ultrasonic sound is that sound that has very small wavelength in the milimeter range and you can not hear Ultrasound since it lies beyond the threshold of human hearing.

TWO WAYS TO USE AUDIO SPOTLIGHT:

Components &Specifications:-

Audio Spotlight Transducer- Light weight,nonmagnetic transducer. 1.27 cm thick and 30.48cm in diameter. It can project a three-degree wide beam of sound over

100 meters distance.

The sound beam Processor/Amplifier-

These are integrated into a system about the size of a traditional amplifier and they use about the same amount of power.

WORKING

Low Beam Angle is required to focus the sound.

Smaller the wave length ,Lesser the Beam angle.

Another way to focus sound is to increase Aperture size of speaker(10m dia for 20Hz)practcally difficult.

Special Features of Audio Spotlight: A comparison with conventional LoudSpeaker:- Creates highly focused beam of sound. Sharper directivity than conventional loudspeaker. Uses inherent non-linearity of air for demodulation. Highly cost effective.

Range of Hearing The human ear is sensitive to

frequency ranging from 20 to 20,000Hz.

If the range of human hearing is expressed as % of shift from the lowest audible frequency to highest it spans a range of 100,000%.

No single loudspeaker element can operate efficiently over such a wide range of frequencies.

Using this it is possible to design a perfect transducer which can work over a wide range of frequency which is audible to human hear.

Application Automobiles-Beam alert signals can be directly

propogated from an announcement device in the dashboard to the driver.

Public announcement-Highly focused announcement in the noisy environment such as subway,airport,parks,traffic intersections etc.

Safety officials-Portable audio spotlighting devices for communicating with a specific person in a crowd of people.

Military applications-Ship to ship communication and ship board announcement.

Entertainment system-In home theatre system(properties of sound can be improved).

Advantages Can focus sound only at the place you

want. The focused or directed sound travels

much faster in a straight line than conventional loudspeaker.

Dispersion can be controlled. Can reduce or eliminate the feed back

from microphones. There is no lag in reproducing the sound.

Future of Audio spotlighting Even the best loudspeaker are subject to distortion

& their omni directional sound is annoying to the people in the vicinity who do no wish to listen.

Audio spotlighting system holds the promise of replacing convetional speakers.It allows the user to control the direction of propogation of sound.

The audio spotlight will force people to rethink their relationship with sound.

Audio spotlight really “put sound where you want it”.

Conclusion Audio spotlight is really going to make a

revolution in sound transmission and the user can decide the path in which audio signal should propogate.

Due to unidirectional propogation it finds application in large number of fields.

Audio spotlighting system is going to shape the future of sound and will serve our ears with magical experience.c

THANK YOU

NON-LINEARITY OF AIR Audio spotlighting exploits the property of non-linearity

of air. When inaudible ultrasound pulses are fired into the air,

it spontaneously converts the inaudible ultrasound into audible sound tones, hence proved that as with water, sound propagation in air is just as non-linear, and can be calculated mathematically.

A device known as a parametric array employs the non-linearity of the air to create audible by-products from inaudible ultrasound, resulting in an extremely directive, beamlike wide-band acoustical source.

This source can be projected about an area much like a spotlight, and creates an actual spatialized sound distant from the transducer.

EXAMPLEPARAMETRIC LOUDSPEAKER- AMAZING AUDIO SPOTLIGHT

The Audio Spotlight uses a beam of ultrasound as a "virtual acoustic source", enabling unprecedented control of sound distribution. The graph to the right shows the real sound field of the The Audio Spotlight uses a beam of ultrasound as a "virtual acoustic source", enabling unprecedented control of sound distribution. The graph to the right shows the real sound field of the Audio Spotlight versus the theoretical maximum directivity of any loudspeaker, panel, dome, or "shower" of the same size. As shown by this comparison, no loudspeaker in the world can approach the level of control provided by Audio Spotlight technology.