Decibels

Decibels (dB) are the units used to express the 'loudness' of audio signal levels. Becuase the measurement of the amplitude of a signal encompasses an extremely wide range of numbers (0 - 1,000,000), a logarithmic equation was created to convert that large scale of numbers into a smaller scale of numbers. The equation, level in decibels = 20 log (A/A0), calculates the relative amplitude of the ratio between two amplitudes. A0 refers to a reference amplitude usually in terms of its maximum value and A refers to a fraction of that reference amplitude, such as a half or a quarter. An example using 1 A0 and 0.5 for A would be: 20 log (0.5/1) = 20 (-0.3) = -6 dB

Created by Jordan Watson