Chapter 19: Acoustics

Acoustics

FUNDAMENTALS OF SOUND

3 Basic Qualities
-Velocity
-Frequency
-Power

Velocity - Mediumin which sound travels

Frequency- Number of Cycles completed per second and is measured in Hz

Power- Is the energy measured in watts.

NOTE:
0dB is the Threshold for human hearing.

130 dB is the threshold of human pain.

HUMAN SENITIVITY TO SOUND

-Healthy Person hears between 20 Hz and 20,000 Hz
-More sensitive to high frequency then low.
-Speech is between 125 Hz - 8,000 Hz.

SOUND TRANSMISSION
Noise- 2 basic problems in controling noise.
-minimizing sound from one space to another.
-reducing noice within a space

STC- Sound Transmission Class.
Note: the higher the STC rating the better the barrier.

STC ratings range from 25- 50.

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