Characteristics of loudspeaker

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Aim:-

To draw the frequency response of a loudspeaker.

 

Apparatus:-

Loudspeaker, carbon resistor, DMM, signal generator, connecting wires, etc.

 

Theory:-

The loudspeaker is an electromechanical transducer that converts an electrical signal into sound. The term loudspeaker can be applied to any of the individual devices (or) drivers or the complete system consisting of an enclosure incorporating one (or) more drivers.

A loudspeaker consists of a  number of drivers to reproduce a wide range of frequencies for high sound pressure level or high fidelity applications most of the loudspeakers have a power response that drops 10 dB to 20 dB from low to high frequencies. Loudspeakers should have a minimal excitation of room resonances, particularly at low frequencies. These loudspeakers should reproduce a smooth, extended frequency response from 20 Hz on up and without exaggerated high frequencies both on-axis & off-axis. In others, it should have minimal roll-off power.

Tabular column:-

Input voltage Vi=3V

 

Frequency in Hz

 

o/p voltage Vo in volts

 

Gain=Vo/Vi

 

 

 

 

 

 

 

 

 

Procedure:-

1) Check the apparatus before making the connections.

2) Connections are made as shown in the circuit diagram.

3) Set the input voltage between 3-4 volt by making the frequency 1 kHz.

4) After the input is set, for different values of frequencies, note down the output voltage obtained.

5) Hence calculate the gain.

 

Nature of graph:-


Result:-

Performed the experiment to determine characteristics of loudspeaker and drawn the frequency response curve of a loudspeaker.



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