Applications
Feedback Prevention
When the overall gain of a sound system is increased,
feedback will occur at frequencies where the system response has peaks. Suppose the system has an
uneven frequency response like that shown in the
following diagram. The frequency at which feedback will occur when gain is increased is about 500Hz. In this case, feedback may be prevented by attenuating
levels at 500Hz by 3dB to 5dB with the
this procedure, sufficient gain in the sound system is
obtained before feedback.
Sound Pressure Level |
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Room Equalization |
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| Frequency | |
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In a sound reinfocement system for a room, the clarity | sound clarity. | ||||
of sound can be adversely affected by | the room | For example, suppose that there is a room frequency | |||
frequency response including standing waves (room | response as shown below. | ||||
resonances), reflections | of | sound, | and | relations | The equalizer sliders are set as shown below. |
between direct and indirect sound. |
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| The overall response after equalization | ||
The | tool to equalize | the room | will then be as follows. | ||
frequency response to a | flat | response | and improve |
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Sound Pressure Level |
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| Frequency | |
The equalizer sliders are set as shown below. |
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The overall response after equalization will then be as follows.
| Frequency response | Frequency response |
Before equalization | of equalizer | after equalization |
Sound Pressure Level
Frequency
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