Definitions for "Audio Frequency"
(AF) The range of frequencies lying within the range of human hearing: approximately 20 to 20,000 Hz.
Signals used for modulation, in the range of 20Hz to 20KHz. For two-way radio, typical range is 300Hz to 3KHz for voice.
The normal range of audible sound with a frequency between 15 Hz and 20,000 Hz.
Keywords:  introduction