
Record Player
Record Player Patent Print "Record Player" Ralph M. Like - November 1, 1948. The phonograph is a device, invented in 1877, for the mechanical recording and reproduction of sound. In its later forms, it is also called a gramophone (as a trademark since 1887, as a generic name in the UK since 1910), or, since the 1940s, a record player. The sound vibration waveforms are recorded as corresponding physical deviations of a spiral groove engraved, etched, incised, or impressed into the surface of a rotating cylinder or disc, called a "record". To recreate the sound, the surface is similarly rotated while a playback stylus traces the groove and is therefore vibrated by it, very faintly reproducing the recorded sound. In early acoustic phonographs, the stylus vibrated a diaphragm which produced sound waves which were coupled to the open air through a flaring horn, or directly to the listener's ears through stethoscope-type earphones. The disc phonograph record was the dominan