Redirected from Analogue disc records
The analogue disc record was the main technology used for storing recorded sound in the 20th century. Its common names included gramophone record (British English), phonograph record (American English), record, album, disc, black disc, vinyl and (more informally) platter.
The first disc recordings for phonographs or gramophones were commercially marketed in 1895, and they gradually overtook the earlier phonograph cylinder as the dominant medium of recorded sound by the 1910s. By the early 1990s digital media such as the compact disc surpassed the analogue disc in popularity, but analogue discs continue to be made (although in very limited quantities) into the 21st century.
It is an audio storage medium, most commonly used for preserving music. A gramophone record almost always consists of a disc engraved with a single concentric spiral groove on one side of the disc, in which a stylus or needle runs, from the outside edge towards the centre. (A small number of early phonograph systems and radio transcription discs started the groove from the inside rather than the edge of the disc, and a small number of novelty records were manufactured with multiple separate grooves.) The record spins at a certain speed, while the needle is held on a mobile arm, which gradually moves toward the centre of the record as it follows the spiral. Since the late 1910s, both sides of the record have usually been used for playing surfaces.
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In the 1890s early discs were usually 7 inches in diameter. By 1910 the 10-inch record was by far the most popular standard, holding about 3 minutes of music or entertainment on a side. 12-inch records were also commercially sold, mostly of classical music or operatic selections, with 5 minutes of music per side.
Such records were usually sold separately, but sometimes in collections held in paper sleeves in a cardboard or leather book, similar to a photograph album, and called record albums. Also, empty record albums were sold that customers could use to store their disc records in.
The older 78 format continued to be mass produced along side the newer formats into the 1950s (and in a few countries, such as India, into the 1960s).
About the same time the most common substance for making disc records became vinyl. All speeds of records were made in various sizes, mainly 7, 10 and 12 inches diameter; the 7-inch being most common for the 45rpm, the 10-inch for the 78 (and the first few years of 33&1/3 production), and the 12-inch for the 33 from the mid 1950s on.
Disc records were extremely popular in their heyday, despite their well-known weaknesses. Throughout most of their period of popularity audio quality was below the best technically possible, but disc records were cheap to manufacture, and easy for the buyer to store and play back.
The discs were fragile. Shellac 78s were brittle and would shatter if dropped. While vinyl records were less subject to breakage they were more prone to being scratched on their unprotected surface, and were more easily warped out of shape by heat. Scratches could cause audio clicks and pops; the needle could skip to the next groove, bypassing that portion of the audio track; or it could skip backward, repeating the same portion of track over and over. Audiophiles would take great care of their records, often playing them on expensive equipment to get the best sound and impart the least wear to the disc. However, even with the best of care, keen ears could often detect slight surface noise and audio degradation after two to five playings of a vinyl record. Repeated use degraded the audio quality further.
On the upside however, they were easy and inexpensive to manufacture, so they could be mass-produced. Also, with the advent of long-playing records, the album cover became more than just packaging and protection, and album cover art[?] became an important part of the music marketing and consuming experience.
A Record cutter would engrave the grooves into the master disc. Early on theses master discs were soft wax, later on a harder lacquer was used.
The soft master would then usually be electroplated with a metal, commonly a nickel alloy. When this metal was removed from the master, it would be a negative master (in some companies' terinology, this was called the master; note difference from master disc above). In the earliest days the negative master was used as a mold to press records sold to the public, but as demand for mass production of records grew, another step was added to the process.
The negative master mold is used to create metal positive discs, each called a mother. These mothers would then in turn be used to make more negatives, each called a stamper. The stampers would be used as the molds for the discs sold to the public. The advantages of this system over the earlier more direct system included ability to make more records more quickly by having multiple stampers pressing records at the same time, more records could be pressed from each record since much used molds would eventually wear out, and spare mothers as back ups.
Starting in the 1980s, vinyl records were gradually replaced in mainstream music consumer markets with the compact disc (CD). Vinyl records continue to be manufactured and sold today, although it is considered to be a niche market[?] comprised of audiophiles, collectors[?], and disc jockeys (DJs).
Some audiophiles dispute the superiority of CDs. The lack of hiss or background crackling is dependent on the quality of the original recording. The quality and clarity of the sound is very much dependent on the quality of the reproduction equipment, for example the DAC (Digital to analog converter).
The background noise one hears on a vinyl record has been compared to the patina[?] of an oil painting -- a part of the work, not an imperfection to be eliminated; moreover, it has been claimed that some pre-CD recordings were made with this patina in mind.
To further cloud the issue, some pop music released on CD has had crackles and hiss added artificially, for effect. See Lo-fi.
wikipedia.org dumped 2003-03-17 with terodump