Audio format
From Free net encyclopedia
An audio format is a medium for storing sound and music. The term is applied to both the physical medium and the format of the content – in computer science it is often limited to the file format, but its wider use usually refers to the physical method used to store the data.
Music is recorded and distributed using a variety of audio formats, some of which store additional information.
[edit]
Timeline of audio format developments
| Year | Physical formats | Content formats |
|---|---|---|
| 1870s | Phonograph cylinder | Mechanical analog; "hill-and-dale" grooves, vertical stylus motion |
| 1895 | Gramophone record | Mechanical analog; lateral grooves, horizontal stylus motion |
| 1930s | Wire recording | Analog; magnetization; no "bias" |
| 1940s | Reel-to-reel, Magnetic Tape | Analog; magnetization; "bias" dramatically increases linearity/fidelity |
| 1948 | Vinyl record | Analog, with preemphasis and other equalization techniques (LP, RIAA). Lateral grooves, horizontal stylus motion. |
| 1957 | Stereophonic vinyl record | Analog, with preemphasis and other equalization techniques. Combination lateral/vertical stylus motion with each channel encoded 45 degrees to the vertical. |
| 1964 | 8-track | Analog, 1/4 inch wide tape, 3 3/4 inches/sec, endless loop cartridge. |
| 1963 | Compact cassette | Analog, with bias, preemphasis, 1/8 inch wide tape, 17/8 inches/sec. 1970: introduced Dolby noise reduction. |
| 1969 | Microcassette | |
| 1970s | Elcaset | |
| 1975 | Betamax Digital Audio | 'Dolby Stereo' cinema surround sound |
| 1982 | Compact Disc (CD) | |
| 1985 | Audio Interchange File Format (AIFF) | |
| 1987 | Digital audio tape (DAT) | |
| 1990s | Digital Compact Cassette | |
| 1991 | MiniDisc | ATRAC |
| 1992 | WAVEform (WAV)
Dolby Digital surround cinema sound | |
| 1993 | Digital Theatre System (DTS)
Sony Dynamic Digital Sound (SDDS) | |
| 1995 | MP3 | |
| 1996 | DVD | |
| 1999 | Super Audio CD (SACD) | Windows Media Audio (WMA) |
| 1999 | The True Audio Lossless Codec (TTA) | |
| 2000 | Free Lossless Audio Codec (FLAC) | |
| 2001 | Advanced audio coding (AAC) | |
| 2002 | Ogg Vorbis | |
| 2003 | DualDisc | |
| 2004 | Apple Lossless (ALE or ALAC) |
[edit]
See also
[edit]