Tagged: 12-inch

16⅔ rpm LP (Long Play) 12 inch record (early 1950 – early 1970s)

Whilst the vast majority of Long Play records were played at 33⅓ rpm, a few records were made to be played at half that speed, 16⅔ rpm (usually listed as 16 rpm). Many of these were spoken word, since the slow speed meant lower fidelity reproduction, but despite this there were a few music releases, mainly from South Africa.

Even though 16 rpm records were rare even at the time, many record decks of the 1950s, 1960s and even into the 1970s came with a 16 rpm speed setting.

The 16⅔ rpm speed was also used for the short-lived in-car Highway Hi-Fi system of 1956 using 7-inch discs, and for the Seeburg Background Music System of 1959 using 9-inch disks.

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Stereophonic LP (Long Play) 12 inch record (1957 – )

The current system for creating stereophonic (2 channel) phonograph discs date back to 1933 when Alan Blumlein, a senior sound engineer at EMI in London, demonstrated a single-groove system in which the stylus moves both horizontally and vertically.

When the 12-inch Long Play record was launched in 1948, it was initially monophonic, and it wasn’t until 1957 that stereophonic LPs were released, by now using a refined version of the EMI system developed by Westrex (a division of Western Electric) called Westrex 45/45 in which each channel drives the cutting head at a 45 degree angle to the vertical.

In late 1957, Audio Fidelity Records and Bel Canto in the US released demonstration stereo LPs, with the the Bel Canto release on multicoloured vinyl. The first mass-produced stereophonic LPs were released in early 1958.

Mono LPs continued to be released alongside stereo LPs for the next ten years or so with major labels ceasing production in 1968, but 7-inch singles continued to be mono for longer, into the 1970s in some cases.

Stereo records produced using the Westrex system played well on a mono record player, and mono records could be played on a stereo system.

In the 1970s, quadraphonic (4 channel) LPs were produced, but were not a great success partly because there were several competing and incompatible systems.

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White label vinyl record (1948 – )

White label vinyl records are generally 12-inch LPs, or 7-inch singles and come with a plain centre label (usually white) and are in plain packaging. The centre label might have handwritten details of the artist and title, or may be rubber stamped, or have a sticker applied.

Some white label records are test pressings made by the pressing plant, usually in quantities of 5 or less,  and then listened to to check the sound quality before pressing larger runs.

Some white label records are produced for promotional purposes, including advance copies sent to retailers or to DJs. Sometimes white labels are used to conceal artist identities, so the record is listened to without prejudice. Dance music producers might produce white label copies to play in dance clubs to gauge crowd response.

Other white label records are unofficial or partially unofficial releases, for example if a remix was made without the consent of the artist or label.

Generally, white label records are not distributed to the general public.

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Record album (late 1900s – 1950s)

Sometime during the late 1900s, record companies began to sell sets of 78rpm disc records in hardback ‘albums’. These were much like photograph albums, but with paper sleeves for multiple 10-inch or 12-inch phonograph discs, and they allowed record companies to sell complete musical works such as operas or classical works. The 78 rpm records of the time were only able to contain around 3 minutes of playing time on the 10-inch version, and 5 minutes on the 12-inch versions, so a longer complete work had to be spread across several discs.

Around the same time, empty record albums became available to allow listeners to store and protect their own discs, write information about the contents on an index page, and display the album on bookshelves.

Record albums eventually came to be used to contain compilations by artist, or by genre, in addition to longer works, and a set of 4-5 discs could contain 8-10 songs. Later releases had cover artwork and liner notes.

With the advent of the Long Play microgroove record in 1948 that could hold the same number of songs on a single disc there was no longer a need for record albums containing several discs, and indeed by the late 1950s the 78 rpm disc itself was being phased out. However, the term ‘album’ continues to be used to describe a collection of songs, whatever the format.

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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 (though some were 16⅔ 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.

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%).

Stereophonic sound was introduced in 1957, 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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