A gramophone record (phonograph record in American English) or vinyl record, commonly known as a "record", is an analog sound storage medium in the form of a flat polyvinyl chloride (previously shellac) disc with an inscribed, modulated spiral groove. The groove usually starts near the periphery and ends near the center of the disc. Phonograph records are generally described by their diameter in inches (12", 10", 7"), the rotational speed in rpm at which they are played (16⅔, 33⅓, 45, 78), and their time capacity resulting from a combination of those parameters (LP – long playing 33⅓ rpm, SP – 78 rpm single, EP – 12-inch single or extended play, 33 or 45 rpm); their reproductive quality or level of fidelity (high-fidelity, orthophonic, full-range, etc.), and the number of audio channels provided (mono, stereo, quad, etc.).
The phonograph disc record was the primary medium used for music reproduction until late in the 20th century, replacing the phonograph cylinder record, with which it had co-existed, by the 1920s. By the late 1980s, digital media, in the form of the compact disc, had gained a larger market share, and the vinyl record left the mainstream in 1991.〔(It's almost final for vinyl: Record manufacturers dwindle in the U.S. ) ''Kitchener - Waterloo Record'' - Kitchener, Ont., January 9, 1991.〕 They continue to be manufactured and sold, and have enjoyed a niche resurgence in the 21st Century. In 2009, 3.5 million units sold in the United States, including 3.2 million albums, the highest number since 1998.〔(【引用サイトリンク】title=2009 R.I.A.A. 2009 Year-End Shipment Statistics )〕〔(Why CDs may actually sound better than vinyl ), Chris Kornelis, January 27, 2015〕 They are especially used by disc jockeys and many audiophiles for various types of music.
The phonautograph, patented by Léon Scott in 1857, used a vibrating diaphragm and stylus to graphically record sound waves as tracings on sheets of paper, purely for visual analysis and without any idea of playing them back. These tracings can now be scanned and digitally converted into audible sound. Phonautograms of singing and speech made by Scott in 1860 were played back as sound for the first time in 2008. Along with a tuning fork tone and unintelligible snippets recorded as early as 1857, these are the earliest known recordings of sound.
In 1877, Thomas Edison invented the phonograph. Unlike the phonautograph, it was capable of both recording and reproducing sound. Despite the similarity of name, there is no documentary evidence that Edison's phonograph was based on Scott's phonautograph. Edison first tried recording sound on a wax-impregnated paper tape, with the idea of creating a "telephone repeater" analogous to the telegraph repeater he had been working on. Although the visible results made him confident that sound could be physically recorded and reproduced, his notes do not indicate that he actually reproduced sound before his first experiment using tinfoil as a recording medium several months later. The tinfoil was wrapped around a grooved metal cylinder and a sound-vibrated stylus indented the tinfoil while the cylinder was rotated. The recording could be played back immediately. The ''Scientific American'' article that introduced the tinfoil phonograph to the public mentioned Marey, Rosapelly and Barlow as well as Scott as creators of devices for recording but, importantly, not reproducing sound.〔''Scientific American''. (1877). The talking phonograph. Scientific American, 14 December, 384.〕 Edison also invented variations of the phonograph that used tape and disc formats.〔Edison Papers. (2010). "The Edison Papers, digital edition: Single document or folder/volume". Retrieved 10 March 2010, from http://edison.rutgers.edu/singldoc.htm. NV17:21〕 Numerous applications for the phonograph were envisioned, but although it enjoyed a brief vogue as a startling novelty at public demonstrations, the tinfoil phonograph proved too crude to be put to any practical use. A decade later, Edison developed a greatly improved phonograph that employed a hollow wax cylinder instead of a foil sheet. This proved to be both a better-sounding and far more useful device. The wax phonograph cylinder created the recorded sound market at the end of the 1880s and dominated it through the early years of the 20th century.
Lateral-cut disc records were developed in the United States by Emile Berliner, who named his system the "gramophone", distinguishing it from Edison's wax cylinder "phonograph" and Columbia's wax cylinder "graphophone". Berliner's earliest discs, first marketed in 1889, but only in Europe, were in diameter, and were played with a small hand-propelled machine. Both the records and the machine were adequate only for use as a toy or curiosity. In the United States in 1894, under the Berliner Gramophone trademark, Berliner started marketing records with somewhat more substantial entertainment value, along with somewhat more substantial gramophones to play them. Berliner's records had poor sound quality compared to wax cylinders, but his manufacturing associate Eldridge R. Johnson eventually improved them. Abandoning Berliner's "Gramophone" trademark for legal reasons, in 1901 Johnson's and Berliner's separate companies reorganized to form the Victor Talking Machine Company, whose products would come to dominate the market for many years.
In 1901, 10-inch disc records were introduced, followed in 1903 by 12-inch records. These could play for more than three and four minutes respectively, while contemporary cylinders could only play for about two minutes. In an attempt to head off the disc advantage, Edison introduced the Amberol cylinder in 1909, with a maximum playing time of 4½ minutes (at 160 rpm), which in turn were superseded by Blue Amberol Records, which had a playing surface made of celluloid, a plastic, which was far less fragile. Despite these improvements, during the 1910s discs decisively won this early format war, although Edison continued to produce new Blue Amberol cylinders for an ever-dwindling customer base until late in 1929. By 1919 the basic patents for the manufacture of lateral-cut disc records had expired, opening the field for countless companies to produce them. Analog disc records would dominate the home entertainment market until they were gradually supplanted by the digital compact disc, introduced in 1983.
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