LP record
Media format
>
The LP is an analog sound storage medium, a phonograph record format characterized by: a speed of 33+1⁄3 rpm; a 12- or 10-inch diameter; use of the "microgroove" groove specification; and a vinyl composition disk. Wikipedia
Speed: 331⁄3 rpm
Capacity: Originally 23 minutes per side, later increased by several minutes, much longer possible with very low signal level
Developed by: Columbia Records
Dimensions: 12 in (30 cm), 10 in (25 cm), 90–240 g (3.2–8.5 oz)
Encoding: Analog groove modulation
Read mechanism: Microgroove stylus (maximum tip radius 0.001 in or 25 μm)
Released: 1948