TIMELINE OF AUDIO FORMATS

TIMELINE OF AUDIO FORMATS

Year	Media formats	Recording formats
1860	Phonautogram	Mechanical analog; sound waveform transcribed to paper or glass
1877	Phonograph cylinder	Mechanical analog; "hill-and-dale" grooves, vertical stylusmotion
1878 - 1916	Ediphone - Dictaphone	Mechanical analog, The Ediphone and subsequent wax cylinders used in Edison's other product lines continued to be sold up until 1929 when the Edison Company folded.
1883	Music roll	Mechanical digital (automated musical instruments)
1895	Gramophone record	Mechanical analog; lateral grooves, horizontal stylus motion
1898	Wire recording	Analog; magnetization; DC "bias"
1925	Electrical cut record	Mechanical analog; electrically cut from amplified microphone signal, lateral grooves, horizontal stylus motion, discs at 7", 10", 12", most at 78 rpm
1930s	Reel-to-Reel, Magnetic Tape	Analog; magnetization; AC "bias" dramatically increases linearity/fidelity, tape speed at 30 ips, later 15 ips and other refined speeds: 7½ ips, 3¾ ips, 1⅞ ips
	Electrical transcriptions	Mechanical analog; electrically cut from amplified microphone signal, high fidelity sound, lateral or vertical grooves, horizontal or vertical stylus motion, most discs 16" at 33⅓ rpm
1936	Tefifon	Electromechanical, vinyl belt housed in a cassette, used an "embossing" technique using a stylus to imprint the information, was the first "audio cassette".
1945	SoundScriber	Analog, 4-6 inch discs, It recorded sound by "pressing" grooves into soft vinyl discs.
1947	Dictabelt (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.
1948	Vinyl Record	Analog, with preemphasis and other equalization techniques (LP, RIAA); lateral grooves, horizontal stylus motion; discs at 7" (most 45 rpm), 10" and 12" (most 33⅓ rpm)
1951	Minifon P55	Analog, magnetic wire on reel, 30 cm/s or about 11.8nbsp;ips was quickly adopted by many governments as being the ultimate "spy" recorder of its day
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.
1957	Dictet	Analog, ¼ tape, 2.48 in/s, (3" reels housed 5.875 x 3 x .4375 inch cassette), developed by the Dictaphone Corp, was the very first dictation machine to use magnetic tape cassettes.
1958	RCA tape cartridge (Sound Tape) (Magazine Loading Cartridge)	Analog, ¼ inch wide tape (stereo & mono), 3¾ 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.
1959	NAB Cart Tape (Fidelipac)	Analog, ¼ inch wide tape in cartridge, 7½ 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.
1962	4-Track (Stereo-Pak)	Analog, 1⁄4-inch-wide (6.4 mm) tape, 3¾ in/s, endless loop cartridge.
1963	Compact Cassette	Analog, with bias. 0.15-inch-wide (3.8 mm) tape, 1⅞ in/s. 1970: introduced Dolby noise reduction.
1964	Sanyo Micro Pack 35 (Channel Master 6546)	¼ inch wide tape housed in a transparent cartridge measuring 2.6 x 2.9 x 1.9 inches, tape was stored on two reels residing atop one another, keeping the cartridge compact.
1965	8-Track (Stereo-8)	Analog, ¼ inch wide tape, 3¾ in/s, endless loop cartridge.
1966	PlayTape	Analog, ⅛ inch wide tape, endless loop cartridge, introduced by "Frank Stanton"
1969	Microcassette	Analog, ⅛ inch wide tape, used generally for notetaking, mostly mono, some stereo (developed in the early 80's). 2.4 cm/s or 1.2 cm/s.
	Minicassette	Analog, ⅛ inch wide tape, used generally for notetaking, 1.2 cm/s
1970	Quadraphonic 8-Track (Quad-8) (Q8)	Analog, ¼ inch wide tape, 3¾ in/s, 4 Channel Stereo, endless loop cartridge.
1971	Quadraphonic Vinyl Record (CD-4) (SQ Matrix)	Analog.
1975	Betamax Digital Audio	Digital.
		Analog. Dolby Stereo cinema surround sound.
1976	Elcaset	Analog.
1978	Laserdisc	Digital/Analog.
1982	Compact Disc (CD-DA)	Digital. Linear PCM (LPCM)
1985		Digital. Audio Interchange File Format (AIFF)
1985		Digital. Sound Designer (by Digidesign) (SD and DIG formats).
1986	High Definition Compatible Digital (HDCD)	Digital. Redbook compatible physical CD containing 20–24 bit information (uses Linear Pulse Code Modulation(LPCM).
1987	Digital Audio Tape (DAT)	Digital.
1991	MiniDisc (MD)	Digital. Adaptive Transform Acoustic Coding (ATRAC)
1992	Digital Compact Cassette (DCC)	Digital, ⅛ inch wide tape, 1⅞ in/s, introduced by Philipsand Matsushita in late 1992, marketed as the successor to the standard analog Compact Cassette.
		Digital. WAVEform (WAV)
		Digital. Dolby Digital surround cinema sound. Also known as Dolby Stereo Digital until 1994.
1993		Digital. Digital Theatre System (DTS), Sony Dynamic Digital Sound (SDDS), MPEG-1 Audio Layer III (MP3).
1994		Digital. TwinVQ.
1997	DVD	Digital. Dolby Digital, Digital Theatre System (DTS)
	DTS-CD	Digital. DTS Audio
1999	DVD-Audio	Digital. 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
		Digital. Windows Media Audio (WMA)
		Digital. The True Audio Lossless Codec (TTA)
2000		Digital. Free Lossless Audio Codec (FLAC)
2001		Digital. Advanced audio coding (AAC)
2002		Digital. Ogg Vorbis
2003	DualDisc	Digital. Multiple formats encoded onto the same disc.
2004		Digital. Apple Lossless (ALE or ALAC)
2005	HD DVD	Digital. Dolby TrueHD, DTS-HD Master Audio
		Digital. OggPCM
2006	Blu-ray Disc	Digital. Dolby TrueHD, DTS-HD Master Audio
2008	slotMusic	Digital. Usually at 320 kbit/s MP3 on microSD or microSDHC
	Blu-spec CD	Digital. PCM
2010	DCP (Digital Cinema Package)	Digital. Auro-3D codec

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