|THE ROBINSON LIBRARY|
|The Robinson Library >> Technology >> Audio Equipment and Devices|
|History of the Phonograph
[fO' no graf'] an instrument for reproducing sounds by means of the vibration of a stylus or needle following a spiral groove on a revolving disc or cylinder
The earliest known phonographic recording device was the phonautograph, invented by Edouard-Leon Scott and patented on March 25, 1857. The device consisted of a horn or barrel 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. The first version made recordings onto a lamp-blackened glass plate. Later versions, such as the one shown here, used a medium of lamp-blackened paper on a drum or cylinder. The phonautograph was primarily a laboratory curiosity for the study of acoustics, used to determine the vibrations per second for a musical pitch and to study sound and speech, and had no means for playing back the recorded sound.
The first practical phonograph that could play back the sounds it had transcribed was invented by Thomas Alva Edison in 1877. The recording medium was a small metal cylinder wrapped in tin foil, which was mounted on an axle that could be rotated. Next to the cylinder was a mouthpiece with a diaphragm. A needle attached to the diaphragm was placed against the cylinder. As someone spoke into the mouthpiece, the cylinder was rotated. The sound waves made the diaphragm and needle vibrate, which in turn made dents in the foil -- the dents representing the original sound waves. The first sounds recorded on the phonograph were Edison's words "Mary had a little lamb." To play the sound back, another needle attached to a diaphragm was placed against the cylinder. As the cylinder was rotated, the dents in the tin foil made the needle and diaphragm vibrate, producing sounds roughly similar to the originals. Edison intended his phonograph to be used primarily as a dictating machine in offices, however, and did very little to improve upon the device.
In 1885, Chichester A. Bell and Charles S. Tainter, invented the Graphophone. It had a cardboard cylinder coated with wax instead of a metal cylinder wrapped in tin foil. The mechanism for recording was similar to that on Edison's machine, except that instead of dents the recording needle produced grooves.
While the graphophone reproduced sound with much greater accuracy and clarity than Edison's phonograph, the wax-coated cylinders had to be stored carefully to prevent the wax from being damaged. What's more, each cylinder had to be individually recorded, making them too expensive for the general public to enjoy. In 1887, Emile Berliner, who had come to the United States from Germany, invented the Gramophone, which used a flat disk instead of a cylinder. He also invented a process for mass-producing the disks, which he called Records. Mass-production greatly reduced the cost of individual records, making it possible for the general public to buy them, meaning that millions of people now had the ability to hear some of the most popular singers of the day without having to travel to a major venue to see them in person.
Early phonographs had spring motors and had to be wound by hand to be played. The motors sometimes ran too fast or too slow, making the music sound odd. The needle mechanisms of such phonographs did not respond to low bass or high treble notes, so bass drums and violins could not be heard clearly. In the mid-1920's, manufacturers began to produce phonographs with electric motors and amplifiers that made them easier to play and greatly improved their sound quality.
Until 1948, all commercial records were played at 78 rpm. They were made of a shellac and clay mixture and were easily broken. LP records, played at 33-1/3 rpm, were developed at the Columbia Broadcasting System Laboratories under the direction of Peter Goldmark, an electrical engineer, and Columbia Records Inc. introduced the LP record to the public in 1948. Unbreakable plastic LP records created a demand for high-fidelity phonographs, and stereophonic phonographs and records were introduced in 1958. By the late 1960's, almost all new phonographs and records were stereophonic.
Library >> Technology >> Audio Equipment and Devices
This page was last updated on September 08, 2017.