SEMINAR ON

AUDIO SPOTLIGHT BASAVARAJ MUDALAGI

USN: 1AY13MT401MECHATRONICS ENGG

Presented by

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.Ultrasonic energy to create extremely narrow beams of sound that behave like beams of light.

Introduction

History Invented by the founder of Holosonics Labs,

Dr. F. Joseph Pompei of MIT. First attempts created a single tone (1975). Audio tone made directive using a

transducer array by Ricoh, Japan (1983). Commercially available in 2000 by the

company Holosonics.  Disney was amongst the first major

corporations to adopt it for use.

AUDIO SPOTLIGHT looks like a disk-shaped loudspeaker trailing a wire with a small laser guide beam

mounted in the middle

When one points the flat side of the disk in your direction, you here whatever sound one’s chosen for you.

Parametric array employs the non linearity of the air to create audible by products from inaudible ultrasonic sound , resulting in extremely directive and beam-like sound

PARAMETRIC LOUDSPEAKER- AMAZING AUDIO SPOTLIGHT

Low Beam Angle is required to focus the sound.

Beam angle of audible sound is very wide, about 360°

The smaller the wave length ,the lesser the Beam angle.

Another way to focus sound is to use loudspeaker with larger Aperture size.

WorkingThe original low frequency sound wave such as

human speech or music is applied into an audio spotlight emitter device.

This low frequency signal is frequency modulated with ultrasonic frequencies.

Since the wavelength is smaller the beam angle will be around 3 degree, as a result the sound beam will be a narrow one with a small dispersion.

AUDIO SPOTLIGHTING EMITTER

Modulated signal travels through the air.Due to the nonlinearity property of air ne

w sounds are formed within the wave. The new frequencies will be added into

the sound wave by the air itself. frequency in the range of 20 Hz to 20

KHz . Since we cannot hear the ultrasonic

sound, we only hear the new sounds that are formed by the nonlinear action of the air

CONVENTIONAL LOUD SPEAKER Vs AUDIO SPOTLIGHT

• CONVENTIONAL SPEAKERS

• AUDIO-SPOTLIGHTG

BLOCK DIAGRAM

HOW TO USE AUDIO SPOTLIGHT ?There are two ways to use Audio Spotlight.

First it can direct sound at a specific target creating a contained area of listening space which is called “Direct Audio”.

Second it can bounce off of a second object creating an audio image which is called the “Projected Audio” or the Virtual mode.

Direct Mode:

Requires a clear line of approach from the sound system unit to the point where the listener can hear the audio. To restrict the audio in a specific area this method is appropriate.

Projected or Virtual mode:

 For this mode of operation the sound beam from an emitter is made to reflect from a reflecting surface.A virtual sound source creates an illusion of sound source that emanates from a surface.

This method is appropriate when we want to send the information to a large number of people.

FeaturesCan focus sound only at the specific place

one’s want.Sharper directivity than conventional

loudspeakers.Uses non-linearity of air for demodulation.Focused or directed sound travel much

faster.No lag in reproducing the sound &

requires low power.

Small size

Single source

Ultimate control in audio placement

Minimizes noise pollution

Ease of installation

Lowest maintenance cost 

Reduced feedback

ADVANTAGES

DISADVANTAGES

Lack of mass production. i.e, each unit must be hand made.

The most common form of distortion is clipping.

APPLICATIONS

AUTOMOBILES RETAIL SALES

PUBLIC ANNOUNCEMENT

MUSEUMS

MILITARY APPLICATIONS ENTERTAINMENT SYSTEMS

two persons can hear different sound standing close to each other

Audio Spotlight speakers allow visitor to enjoy music while other read nearby peace & quiet

Audio/video conferencingSound Bullets

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. 

Due to the unidirectional propagation 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..

CONCLUSION