Digital audio is audio or sound data represented in digital form.
An analog signal can be converted to a digital signal at a given sampling rate and bit resolution. It may contain multiple channels (2 channels for stereo or more for surround sound). Generally speaking, the higher the sampling rate and bit resolution, the more fidelity, as well as the greater quantity of digital data.
An analog audio signal can be converted to a digital audio signal with
an analog-to-digital converter (ADC).
Some audio signals such as those created by digital synthesis originate entirely in the digital domain, in which case analog to digital conversion does not take place.
A digital audio signal may be altered by applying digital signal processing, where it may be filtered or have effects applied.
The digital audio signal may be stored or transmitted. Digital audio storage can be on a CD, an MP3 player, a hard drive, or any other digital data storage device. Audio data compression techniques, such as MP3, are commonly employed to reduce the file size. Digital audio can be streamed to other devices.
A digital audio signal can be converted back to an analog signal with a digital-to-analog converter (DAC).
The preceeding takes material from the following article:
Wikipedia contributors, "Digital audio," Wikipedia, The Free Encyclopedia (accessed December 24, 2008).