Properties of sound

The frequency of a sound wave is related to the pitch that is heard:

  • high frequency sound waves are high pitched;
  • low frequency sound waves are low pitched.

The amplitude of a sound wave is related to the volume of the sound:

  • high amplitude sound waves are loud;
  • low amplitude sound waves are quiet.
Trace one: peak heights half unit, peak to peak distance 1.5 units. Trace two: peak heights one unit, peak to peak distance 1.5 units. Trace three: peak heights one unit, peak to peak one unit.

Oscilloscope traces showing the following sounds:

  1. quiet, low pitch sound
  2. loud, low pitch sound
  3. loud, high pitch sound

The cochlea is only stimulated by a limited range of frequencies.

This means that humans can only hear certain frequencies.

The range of normal human hearing is 20 Hz to 20,000 Hz (or 20 Hz to 20 kHz).