Phonograph: Encyclopedia II - Phonograph - History

Phonograph - History

Phonograph - The phonautograph

The earliest known invention of a phonographic recording device was the phonautograph, invented by Edouard-Leon Scott and patented on March 25, 1857. It could transcribe sound to a visible medium, but had no means to play back the sound after it was recorded. The device consisted of a horn that focused sound waves onto a membrane to which a hog's bristle was attached, causing the bristle to move and enabling it to inscribe a visual medium. Initially, the phonautograph made recordings onto a lamp-blackened glass plate. A later version used a medium of lamp-blackened paper on a drum or cylinder—an arrangement to which Thomas Edison's later invention would bear striking resemblance. Other versions would draw a line representing the sound wave on to a roll of paper. The phonautograph was a laboratory curiosity for the study of acoustics. It was used to determine the vibrations per second for a musical pitch and to study sound and speech; it was not widely understood until after the development of the phonograph that the waveform recorded by the phonautograph was a record of the sound wave that needed only a playback mechanism to reproduce the sound.

Phonograph - Phonograph theory

Charles Cros, a French scientist, produced a theory (April 18, 1877) concerning a phonograph. Cros's work was only a theory, though, and he did not manufacture a model.

Phonograph - The first phonograph

Thomas Alva Edison announced his invention of the first phonograph, a device for recording and replaying sound, on November 21, 1877 and he demonstrated the device for the first time on November 29 (he patented it on February 19, 1878; US Pat. No. 200,521). Edison's early phonographs recorded onto a phonograph cylinder using an up-down (vertical) motion of the stylus. Edison's early patents show that he also considered the idea that sound could be recorded as a spiral onto a disc, but Edison concentrated his efforts on cylinders, since the groove on the outside of a rotating cylinder provides a constant velocity to the stylus in the groove, which Edison considered more "scientifically correct". Edison's patent specified that the audio recording was embossed, and it was not until 1889 that engraved recordings were patented by Chichester Bell and Charles Sumner Tainter. They named their version the Graphophone.

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Adapted from the Wikipedia article "History", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki