Timeline of recording sound
-the phonograph
-the tinfoil phonograph (1887), speaking machine (Thomas Edison)

-Hill & Dale vertical grooves
-Wax Cylinder (1889)
-The Gramophone/Shellac discs (1887)

-Instantaneous Disc (1929), (Lacquer, 1934)
-Microgroove disc (LP, 1948, USA), (EP, 1949, USA)
-Magnetic Recording (tape)
-Wire Recorder (Woody Guthrie)
Configuration:
-full track mono
-twin track
-4, quarter length track stereo (1+3 one way, 2+4 the other)
-compact cassette (1963)

-Pulse Code Modulation (PCM), Alec Reeves (1937)
-NHK R+D (1967) 12-bit, 30 KHz mono, then 13-bit, 32 KHz stereo
-Denon (1972)-DN-023R (8-track)

-Sony PCM-1 (1977), F1 1981-PAL/NTSC signals
-Betamax, U-matic, VHS
-E1AG (14-bit)
-Sony Phillips Compact Disc (1982): Optical Laser, 74 min duration, 16-bit, 44.1 kHz, Pits and Land.
-Sony Phillips CD-R/CD-RW (1998): Photosensitive dye (burning), Audio+Data, 80 min, 10 years duration, digital (Sony DASH, Mitsubishi prodigi)

-Sony DAT (1987): Smaller than a cassette, 16-bit, 44.1, 48 or 32 kHz, Helical scan, expensive + RIAA concern, DDS (Digital Data Storage)
-Sony MiniDisc (MD, 1992): Magneto-optical tech (formative layer), Lossy ATRAC (Later Hi-MD), 80 min. Low uptake.
-Phillips Matsushita DCC (1992)
-HDD & Solid state
-MPMan (1998)

-iPod (2001), Spotify (2006)