An audio format is a medium for sound recording and reproduction. The term is applied to both the physical recording media and the recording formats of the audio content—in computer science it is often limited to the audio file format, but its wider use usually refers to the physical method used to store the data. Note on the use of analog compared to digital in this list; the definition of digital used here for early formats is that which is represented using discrete values rather than fluctuating variables. A piano roll is digital as it has discrete values, that being a hole for each key, unlike a phonograph record which is analog with a fluctuating groove.

Music is recorded and distributed using a variety of audio formats, some of which store additional information.

Timeline of audio format developments

YearPhysical media formatsRecording formats
1805PanharmoniconDigital, automated sound reproducing machine.
1817ApolloniconDigital, automated sound reproducing machine.
1851Piano CylinderDigital, automatically played by means of revolving cylinders
1877Tinfoil PhonographIn 1877, Thomas Edison invented the first recorder that could also play back Analog; sound waveform transcribed to tinfoil
1883Piano rollA piano roll used in a player piano Digital (vacuum-operated piano)
1886Music Box disc8'' disc for playback on a music box Digital (vacuum-operated music box)
Late 1880sBrown Wax cylinderA collection of brown wax cylinders, vertical-groove Analog; vertical groove, vertical stylus motion – could be re-recorded
Organ CobMechanical digital (vacuum-operated organ)
Ediphone, DictaphoneA Dictaphone cylinder for voice recording Analog, the Ediphone and subsequent wax cylinders used in Edison's other product lines continued to be sold up until 1929 when the Edison Manufacturing Company folded.
1894Pathé cylinderThe vertical-groove pathé cylinder Mechanical analog; vertical grooves, vertical stylus motion
18977'' 78rpm Record (Emile Berliner Patent)Mechanical analog; lateral groove, horizontal stylus motion – made from hard rubber
1898Wire recordingA Peirce 55-B dictation wire recorder from 1945 Analog; magnetization; DC bias
190110'' 78rpm Record78rpm record - playable on modern turntables Mechanical analog; lateral groove, horizontal stylus motion – made from shellac
1902Edison Gold Moulded RecordEdison's "gold moulded" black wax cylinder record Mechanical analog; vertical groove, horizontal stylus motion – made from hard black wax – 160 rpm standard – 100 threads per inch
190312'' 78rpm recordMechanical analog; lateral grooves, horizontal stylus motion
Phonograph PostcardA phonograph post card, playable on 78rpm turntables Mechanical analog; lateral groove, horizontal stylus motion
1905Centre-start phonograph RecordA modern vinyl LP with a centre-start cut Mechanical analog; lateral groove, horizontal stylus motion, starts from the centre of the disc
Pathé discThe vertical-groove pathé disc Mechanical analog; vertical groove, vertical stylus motion
1907Indestructible RecordIndestructible Record cylinder, vertical groove. Constructed of black celluloid on a cardboard core with metal bands at each end Mechanical analog; vertical groove, vertical stylus motion – made from black celluloid with cardboard and inner metal bands
1908Amberol Cylinder RecordThe Edison "Amberol" cylinder record, vertical groove Mechanical analog; vertical groove, vertical stylus motion – made from hard black wax – 160 rpm standard – 200 threads per inch
1912Diamond DiscThe Edison vertical-groove "diamond disc" Mechanical analog; vertical groove, vertical stylus motion – made from Bakelite or china clay
Blue Amberol cylinder recordThe Edison vertical-groove "Blue Amberol" cylinder Mechanical analog; vertical groove, vertical stylus motion – made from blue celluloid with plaster of paris core – 160 rpm standard – 200 threads per inch
1924Electrical cut recordMechanical analog; electrically cut from amplified microphone signal, lateral groove, horizontal stylus motion, discs at 7", 10", 12", most at 78 rpm
1930Filmophone flexible recordA red Filmophone record Mechanical analog; lateral groove, horizontal stylus movement – made from cellulose of various colours – 78 rpm
Durium Record or Hit of the Week RecordsA brown Durium 78 rpm record Mechanical analog; lateral groove – made from paper coated in a brown resin (Durium)
1930sReel-to-reel, magnetic tapeStudio master tape reel Analog; magnetization; AC "bias" dramatically increases linearity/fidelity, tape speed at 30 ips, later 15 ips and other refined speeds: 7+1⁄2 ips, 3+3⁄4 ips, 1+7⁄8 ips
Electrical transcriptionsMechanical analog; electrically cut from amplified microphone signal, high fidelity sound, lateral or vertical groove, horizontal or vertical stylus motion, most discs 16" at 33+1⁄3 rpm
1942SoundScriberGreen, vertical groove Sound Scriber disks Mechanical analog; vertical groove, 4–6 inch discs, it recorded sound by pressing grooves into soft vinyl discs
1947Dictabelt (Memobelt)Analog, medium consisting of a thin, plastic belt 3.5" wide that was placed on a cylinder and rotated like a tank tread, developed by the Dictaphone company in 1947
1948Vinyl LP record (Columbia)Analog, with preemphasis and other equalization techniques (LP, RIAA); lateral groove, horizontal stylus motion; discs 7", 10" and 12" at 33+1⁄3 rpm, 1st LP Columbia ML 4001 Milstein, Mendelssohn Violin Concerto
1949Vinyl 45 record (RCA)A 7'' 45rpm record Analog 45 rpm vinyl 7" disk, first 45 pressed "PeeWee the Piccolo" RCA 47-0147 Indianapolis
1950TefifonA stand-alone Tefifon player with cartridge loaded Electro–mechanical analog, vinyl belt housed in a cassette, used an embossing technique using a stylus to imprint the information, was the first thing to resemble a modern audio cassette
16 2/3rpm vinyl recordA label close-up on a 16 rpm vinyl Mechanical analog; lateral groove, horizontal stylus motion – played at half the regular speed of an LP
1951Minifon P55Minifon cassette Analog, magnetic wire on reel, 30 cm/s or about 11.8 ips was quickly adopted by many governments as being the ultimate "spy" recorder of its day
1957Stereophonic vinyl recordAn early stereo record label Analog, with pre-emphasis and other equalization techniques. Combination lateral/vertical stylus motion with each channel encoded 45 degrees to the vertical
DictetCassette for the Dictaphone Dictet dictation machine Analog, 1⁄4 tape, 2.48 in/s, (3-inch reels housed 5.875 × 3 × .4375 inch cassette), developed by the Dictaphone Corp
1958RCA tape cartridge (Sound Tape) (Magazine Loading Cartridge)The cassette format created by RCA Analog, 1⁄4 inch wide tape (stereo & mono), 3+3⁄4 in/s & 1.875 in/s, one of the first attempts to offer reel-to-reel tape recording quality in a convenient format for the consumer market
1959NAB Cart Tape (Fidelipac)The cartridge known as a "Fidelipac" Analog, 1⁄4 inch wide tape in cartridge, 7+1⁄2 in/s & 15 in/s, Introduced in 1959 by Collins Radio, the cart tape format was designed for use by radio broadcasters to play commercials, bumpers and announcements
Synchrofax Sound PaperMagnetic coating on paper.
19624-Track (Muntz Stereo-Pak)Analog, 1⁄4-inch-wide (6.4 mm) tape, 3+3⁄4 in/s, endless-loop cartridge
1962Compact cassetteVariants of the Compact Cassette Analog, with bias. 0.15 inches (3.81 mm) tape, 1+7⁄8 ips. 1970: introduced Dolby noise reduction
1964Sanyo Micro Pack 35 Channel Master 6546 Westinghouse H29R1The micro pack recording system, intended for dictation 1⁄4 inch wide tape housed in a transparent cartridge measuring 2.6 × 2.9 × 1.9 inches, tape was stored on two reels residing atop one another, keeping the cartridge compact
1964SabamobilA cartridge format for embedding and easy handling usual 3-inch-tape-reels with 1⁄4 inch tape, compatible to reel-to-reel audio recording in 3+3⁄4 ips.
19658-Track (Stereo-8)The inside of an 8-track cartridge Analog, 1⁄4 inch wide tape, 3+3⁄4 in/s, endless-loop cartridge
DC-International cassette systemDC-International cassette Analog cassette format introduced by Grundig, Telefunken and Blaupunkt: 120 × 77 × 12 mm cassette with 1⁄4 inch wide tape run at 5.08 cm per second.
1966PlayTapeTwo PlayTape cartridges Analog, 1⁄8 inch wide tape, endless-loop cartridge, introduced by Frank Stanton
1969MicrocassetteA comparison of sizes for the Microcassette and Minicassette Analog, 1⁄8 inch wide tape, used generally for note taking, mostly mono, some stereo (developed in the early '80s). 2.4 cm/s or 1.2 cm/s
MinicassetteAnalog, 1⁄8 inch wide tape, used generally for note taking, 1.2 cm/s
1970Quadraphonic 8-Track (Quad-8) (Q8)A Quadraphonic 8-Track Cartridge Analog, 1⁄4 inch wide tape, 3+3⁄4 in/s, 4-channel stereo, endless-loop cartridge
1971Quadraphonic Vinyl Record (CD-4) (SQ Matrix)An SQ quadraphonic record Analog, introduced by CBS Records for matrix and RCA / JVC for CD-4 Recorded two tracks on both stereo channels, requiring a decoder to hear all four tracks. Despite this, the format is playable on any LP turntable.
1971HiPacAnalog, a successor of the 1966 PlayTape, using tape width of the 1963 Compact Cassette, Japan only
1976Dolby Stereo cinema surround soundAnalog
ElcasetElcaset (left) compared to a typical compact cassette (right) Analog, name comes from "L-Cassette/Large Cassette"
1982Compact Disc (CD-DA)The underside of a compact disc Digital. Linear PCM (LPCM)
1986High Definition Compatible Digital (HDCD)An HDCD album Digital. Redbook compatible physical CD containing 20–24 bit information (uses linear pulse-code modulation (LPCM))
1987Digital Audio Tape (DAT)A DAT tape Digital. This audio format famously caused controversy among recording companies when released due to the potential of perfect digital copies to increase piracy
1988AIFF (file format)Digital. Audio Interchange File Format (AIFF)
1992Digital Compact Cassette (DCC)A Digital Compact Cassette Digital, 1⁄8 inch wide tape, 1+7⁄8 in/s, introduced by Philips and Matsushita in late 1992, marketed as the successor to the standard analog compact cassette
WAV (file format)Digital. Named after the waveform created by a sound wave.
Dolby Digital Cinema SoundDigital. Also known as Dolby Stereo Digital until 1994.
MiniDisc (MD)A red, translucent MiniDisc cartridge Digital. Adaptive Transform Acoustic Coding (ATRAC)
1993DTS, SDDS, MP3 (file formats)A photo of a theatrical DTS CD-ROM disc used for the original 1993 release of Jurassic Park Digital. Digital Theatre System (DTS), Sony Dynamic Digital Sound (SDDS), MPEG-1 Audio Layer III (MP3)
1994TwinVQDigital.
1995RealAudio
1997DTS-CDDigital. DTS audio
1998WavPack (file format)Digital. PCM, lossless compression (2002 hybrid compression) (2016 DSD support)
1999DVD-AudioDigital. Including Meridian Lossless Packing (MLP), Linear PCM (LPCM), Dolby Digital (AC-3) and Digital Theatre System (DTS)
Super Audio CD (SACD)Digital. Direct Stream Digital
WMA (file format)Digital. Windows Media Audio
TTA (file format)Digital. The True Audio Lossless Codec.
2000FLAC (file format)Digital. Free Lossless Audio Codec (open, non-proprietary, patent-and-royalty-free)
Ogg Vorbis (file format)Digital. Vorbis compressed audio format (open, non-proprietary, patent-and-royalty-free)
DSDIFF (file format)Digital. DSD, optional DST compression
APE (file format)Digital. Monkey's Audio
2001AAC (file format)Digital. Advanced Audio Coding
2002WSD (file format)Digital. DSD
2004ALE or ALAC (file formats)Digital. Apple Lossless
2005DSF (file format)Digital. DSD
2008slotMusicA SlotMusic microSD card: an early attempt to sell pre-recorded music on an SD card Digital. Usually at 320 kbit/s MP3 on microSD or microSDHC.
Blu-spec CDDigital. PCM
2012Opus (file format)Digital. Opus lossy audio coding format (IETF standard, open, non-proprietary, royalty-free)

See also

External links