User Guide

Amplitude – The strength of a sound’s vibration measured in Decibels (dB). This corresponds to the

musical term Loudness (figure 4).

Harmonic Content – A sound is made up of simple vibrations at many different frequencies

(called harmonics) which give a sound its particular character. This corresponds to the musical

term timbre or tone color. A harmonic sound, such as a vibrating string, is one in which the

harmonics are mathematically related by what is called the harmonic series. These sounds are

typically pleasing to the ear and generally the consecutive vibrations have the same characteristic

shape or waveform. An inharmonic sound, such as a crash cymbal, is one in which the harmonics

are not mathematically related. Their waveforms look chaotic. White noise is an inharmonic sound

that contains equal amounts of all frequencies. A frequency spectrum is a graph of harmonics vs.

their amplitude; a waveform is a graph of the amplitude of a sound vs. time (figure 5).