Tagged: 12-inch

LP (Long Play) 12 inch record (1948 – )

The LP (Long Play) record is an audio format for phonograph records, introduced by Columbia Records in 1948 and still in use today.

LP records are made of vinyl (either virgin or recycled) and together with a playing speed of 33⅓ rpm and the use of microgrooves, allow for a playing time of around 45 minutes. Previously, 78 rpm records had a playing time of just around 3-4 minutes per side, so an ‘album’ of records was sold as a set, and this name continued to describe a collection of songs on a single disc.

Each side of an LP contains a single continuous groove, with an average length of 460 m.

LP records are generally 12 inches in diameter, but 10 inch LPs have also been produced at different times. The amount of vinyl in an LP is generally 130 g, but some records were produced with less (sometimes as little as 90 g). Modern high-fidelity LPs tend to use more, such as 180 g. Generally LPs are pressed on black vinyl, but coloured vinyl and picture discs (with a card sandwiched between two clear sides of vinyl) have been produced, as have shaped vinyl and even neon vinyl.

By as early as 1952, LPs represented 16.7% of unit sales, rising to 24.4% in 1958 (by then, most of the remainder was 45 rpm singles, 78 rpm only representing 2.1%).

Stereo sound was introduced in 1958, and quadraphonic records were sold in the 1970s for a time.

The LP had no serious competitors for long-playing recordings until the 1970s when the Compact Cassette improved in quality, and then in the 1980s with the introduction of the Compact Disc. LPs ceased to be a mainstream format in the early 1990s, but continue to be produced in small but increasing numbers.

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Preservation / Migration

Compact LaserDisc (1986)

Compact LaserDiscs were 12-inch LaserDiscs that combined a complete music album (as would be found on the equivalent Compact Disc) in digital audio, along with music videos for some of the tracks. When played as an audio album, the screen would show a picture of the sleeve and the name of the track.

Around just seven titles were released by Pioneer Artists in 1986, for distribution in the US.

The name is a bit of a misnomer as they were anything but compact, but it was meant to emphasise that these were essentially a Compact Disc album with added videos. They are very similar in concept to CD Video, except able to hold an entire music album.

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Pye magnetic disc (1953 – late 1950s)

From around 1953 to the late 1950s the UK company Pye produced the Record Maker. This device allowed the user to record onto pre-grooved 12-inch discs that had a magnetic coating. Users could record to the disc at one of four different speeds (16⅔, 33⅓, 45 and 78rpm) but the slower the speed, the poorer the quality of recording.

The Pye Record Maker could also be used to play ordinary phonograph records, with an optional pick-up head attachment.

Telefunken also made a similar machine, but this could not play phonograph discs, used a larger centre hole, and had a single speed of 10rpm.

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dbx disc (1979 – 1982)

dbx was a noise-reduction system that was employed on a number of 12-inch LPs in the late 1970s and early 1980s..

The dbx system was premiered in 1973 and a promotional disc produced, but no record companies were interested. It wasn’t until 1979 that BSR, a UK producer of turntables, acquired the dbx company and persuaded several record companies to begin producing discs using dbx Type II encoding.

dbx used linear decibel compounding to compress the signal when recording, and expand it on playback. It meant that surface noise was almost completely eliminated, and the dynamic range of vinyl records could be greatly increased. In addition, dbx releases were made on heavy virgin vinyl and produced from the original master tapes. However, playing back dbx discs required a decoder, and without one playback sounded poor. This was one of the reasons it failed in the marketplace.

With a dbx encoder, users could also record onto tape with dbx noise reduction, and playback from dbx encoded tape recordings, but by this time, Dolby B was already widespread as a noise reduction system for tape.

It appears that less than 200 titles were made available, and no new releases appear to have been made after 1982.

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Timecode vinyl (2001 – )

Timecode vinyl is a 12-inch vinyl phonograph record used to control vinyl emulation software (also known as digital vinyl systems) and was first introduced in 2001 as part of the Final Scratch system.

Vinyl emulation software allows DJs to control the playback of music stored on a computer by manipulating the record as if it were a standard disc. The timecode records are played on a standard turntable, and the output of this is passed through an interface box (some DJ turnables may have this built in) and fed into the emulation software on the computer.

Vinyl emulation software allows any music to be played and manipulated even if it is not available on phonograph disc.

Popular current makers of vinyl emulation software include Serato and Traktor, and they produce timecode vinyl in a variety of colours.

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SQ Quadraphonic (1971 – 1979)

SQ Quadraphonic (from ‘Stereo Quadraphonic’) was a system for providing quadraphonic sound from four speakers on vinyl records. It was introduced by CBS Records in 1971, and was adopted by a number of other record companies including EMI and Sony.

It was a matrix format, so the four channels were encoded into the stereo grooves of a 12-inch LP and then decoded back to four channels. As the grooves were slightly broader than a standard LP, playing time on an SQ record was reduced.

Of the different quadraphonic systems for vinyl, SQ has the largest discography and this was partly because SQ records were fully compatible with stereo equipment. Some early Compact Discs still used the SQ mix.

Consumers needed to buy an SQ decoder to take advantage of quadraphonic sound, but early versions provided poor separation. The sound separation of the SQ system was greatly improved by the introduction of SQ Full Logic decoding in 1975, but by this time all quadraphonic systems were declining in popularity and by the end of the 1970s, virtually no SQ Quadraphonic LPs were being released.

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Laser-etched vinyl (1980 – )

Phonograph records with etchings on one side have existed since the early 1900s, and etched centre labels were used from the very start of phonograph record production.

Laser-etching is different as it’s possible to etch a pattern onto the playable surface of a vinyl record without any discernible difference to the sound quality.

The first vinyl record to employ laser-etching was the 1980 12-inch LP ‘True Colours’ by Split Enz. The logo from the album cover, as well as other shapes, were etched into the vinyl in a manner that if hit by a light reflected polychromatic colours.

Although the technique has been employed on a few other releases, most etchings on vinyl are done on the non-playable side.

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12-inch 78 rpm record (1903 – mid 1950s)

12-inch 78 rpm records were introduced slightly later than the 10-inch version, becoming widely available in 1903.

They increased the playing time to 4 or 5 minutes per side, over the 10-inch version’s 3 minutes and just 2 minutes for contemporary cylinders.

Despite their longer playing time, there were fewer releases on the 12-inch size, and they appear to have died out in the mid-1950s.

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LaserDisc (1983 – 2001)

LaserDisc was the first optical videodisc format. MCA and Philips demonstrated a laser videodisc in 1972, and it was initially marketed in 1978 in the US as MCA DiscoVision, with the first release being ‘Jaws’.

From 1980, it became known as LaserDisc, although the official name of the format was LaserVision until the early 1990s. It was released in Japan in 1981, and finally reached Europe in 1983. The technologies and concepts behind LaserDisc are the foundation for later optical disc formats, including Compact Disc, DVD, and Blu-ray.

The most common size of LaserDisc was 30 cm, allowing for up to 60 minutes per side. This is made up of two single-sided aluminum discs layered in plastic. The spiral track of a 30cm LaserDisc is 42 miles long. After one side was finished playing, a disc has to be flipped over in order to continue watching a movie, and some titles fill two or more discs. A number of 20cm LaserDiscs were also produced, and these ‘EP’ sized discs were often used for music video compilations.

There were also 12 cm CD-Video discs, and Video Single Discs. A CD-Video carried up to five minutes of LaserDisc video content (usually a music video), and up to 20 minutes of digital audio CD tracks. Video Single Discs carried only video, and were only popular in Japan.

LaserDisc was also adapted for data storage, such as for the BBC Domesday Project (as an LV-ROM) and for computer games on the Pioneer LaserActive (as an LD-ROM).

Many early LaserDiscs used a substandard adhesive to sandwich together the two sides of the disc, and this can attack the reflective aluminium layer, causing it to oxidize and lose its reflective characteristics. This was known as ‘laser rot’.

Although it was capable of higher-quality video and audio than other video formats such as VHS and Betamax, it never gained widespread use in the US, largely owing to high costs for the players and the discs. It also remained largely obscure in Europe, but was more popular in Japan and some countries of South East Asia. A total of 16.8 million LaserDisc players were sold worldwide.

The last LaserDisc titles were released in the US in 2000, and in Japan in 2001. Pioneer continued to produce players until 2009.

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Preservation / Migration

Capacitance Electronic Disk (CED) / SelectaVision (1981 – 1986)

Capacitance Electronic Disc (CED) was an analogue video disc playback system developed by RCA, using a special stylus and high-density groove system similar to phonograph records. The name ‘SelectaVision’ was RCA’s brand name for the CED system. It was also used for some early RCA brand VCRs.

The 12-inch discs were crafted using PVC blended with carbon to allow the disc to be conductive, and a thin layer of silicone was applied to the disc as a lubricant. Discs were stored in a caddy from which the disc was extracted by the player. CEDs could store 60 minutes of video per side, so almost all films needed to be flipped over at some point.

A stylus with a titanium electrode layer rides in the grooves with extremely light tracking force (65 mg), and an electronic circuit is formed. The video and audio signals are encoded into vertical undulations in the bottom of the groove, that the stylus rides over; the varying amount of air pressure between the stylus tip and the undulations under it controls the capacitance between the stylus and disc. This varying capacitance is then decoded into video and audio signals by the player’s electronics.

CED players, because they have fewer precision parts than a VCR, cost about half as much to manufacture. The discs themselves could be inexpensively duplicated, stamped out on slightly-modified audio gramophone record presses. Since CEDs were a disc-based system, they did not require rewinding. Early discs were generally monaural, but later discs included stereo sound. Monaural CED disks were packaged in white protective caddies while stereo disks were packaged in blue protective caddies.

RCA estimated that the number of times a CED could be played back, under ideal conditions, was 500. Since the CED system used a stylus to read the discs, it was necessary to regularly change the stylus in the player to avoid damage to the disc. When a disc began to wear, video and audio quality would severely decline.

First conceived in 1964, by which time it was released in 1981 it was already outmoded by LaserDisc, and the emerging Betamax and VHS videocassette formats. Sales for the system were nowhere near projected estimates (although the discs themselves sold well), and in 1984, player production ended, with discs ending production in 1986. Over 270 titles were released in the UK.

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