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Phonograph, also known as record player, electromechanical instrument for reproducing sound from a record. A record is a vinyl disk that has a spiral groove with tiny bumps on the walls of the groove; the bumps encode a musical or other type of recording. has fou ....

Middle of Essay
.... in the tonearm. These impulses are conducted by wire leads to an electronic amplifier and then to one or more loudspeakers. The first practical phonograph was built by the American inventor Thomas Edison in 1877. Edison recorded sound on a cylinder, which was then rotated against a needle. The needle moved up and down in the grooves of the cylinder, producing vibrations that were amplified by a conical horn. Because of the vertical movement of the needle, this recording method was called the "hill-and-dale" process. Edison had intended the phonograph to be used primarily as a dictating machine in offices. However, with the invention of the flat- ....