Theory of Sound
What is sound? O Sound is a signal, which is a varying wave
carrying information.
How Does Sound Work? O Sound is vibrations, small waves of pressure
in the air O The signal goes from one medium to the next, but keeps its basic shape
Eventually‌.
How do we Measure Sound? O Sound is a repeated up/down pattern
O A Wavelength is the measurement between
the crest of two waves in a sound signal:
Sound is Affected by‌
Amplitude O The height and depth that the signal makes
on each cycle and is related to loudness.
Small waves are quiet
Big vertical waves are loud
Frequency O Is the amount of times a signal wave repeats per
second, so if it repeats 10 times per second, that's a frequency of 10 Hertz (Hz) O If the signal repeats more quickly, we hear that as a high sound
O Or if it slows down, we a hear a lower sound.
Pitch O Pitch is a result of frequency. O Sound waves with low frequency are said to
have low pitch, whereas sound waves with high frequency are said to have high pitch. O Pitch is what you hear when the frequency changes
Intensity Source of Sound
Decibels
Boeing 747
140
Civil Defense Siren
130
Jack Hammer
120
Rock Concert
110
Lawn Mower
100
Motorcycle
90
Garbage Disposal
80
Vacuum Cleaner
70
Normal Conversatio n
60
Light Traffic
50
Background Noise
40
Whisper
30
Loudness cannot be assigned a specific number, loudness is percepetion, but intensity can be measured in decibels (db) and hertz (hz). The human ear is more sensitive to high sounds, so they may seem louder than a low noise of the same intensity. Decibels and intensity can be measured with sound recording instruments.
Listening Test
Draw the Sound What do the following look like? O 3 different levels of intensity for a whisper, hoover and a jack hammer O Amplitude O Frequency O Quiet and loud pitch, O Deeper and higher pitch
How Can This help You as a Sound Designer?
Recording Settings
Sound Editing Information
Frequency Analysis
Amplitude Analysis
How Will This Help Your Sound?