The audio on a music CD is encoded in a special, standardized data format known as "Red Book." Researchers spent nearly a decade developing Red Book as a means of replacing vinyl records. Over the years, the compact disc has increased in versatility and the audio CD is now only one of its nine approved formats.
History
Development of the music CD format began in 1970 by the Philips Corporation. In 1979, Philips teamed with Sony to establish the new format as an industry standard.
Specifications
The audio is encoded in two channels at 22,050 KHz per channel, for a combined sample rate of 44.1 KHz.
Process
The encoding process involves using a special method known as "linear pulse code modulation" (also referred to as "LPCM" or "PCM").
Limitations
According to the format's specifications, the maximum play time for an audio CD is 74 minutes; the minimum play time for a track is 2 seconds.
Fun Fact
The Red Book format gets its name from a book that outlines the technical specifications for the music CD format. The book has a red cover.
Tags: music format, play time