An audio signal is a representation of sound, typically as an electrical voltage. Audio signals have frequencies in the audio frequency range of roughly 20 to 20,000 Hz (the limits of human hearing). Audio signals may be synthesized directly, or may originate at a transducer such as a microphone, musical instrument pickup, phonograph cartridge, or tape head. Loudspeakers or headphones convert an electrical audio signal into sound. Digital representations of audio signals exist in a variety of formats.
Famous quotes containing the word signal:
“Perhaps having built a barricade when youre sixteen provides you with a sort of safety rail. If youve once taken part in building one, even inadvertently, doesnt its usually latent image reappear like a warning signal whenever youre tempted to join the police, or support any manifestation of Law and Order?”
—Jean Genet (19101986)