Tagged: 1940s

Formats current at any point during the years 1940-1949

Acetate / lacquer disc (late 1920s – )

Acetate discs (also known as lacquers or instantaneous discs) are a type of phonograph record created using a recording lathe to cut a groove in real-time, rather than mass-produced from moulds.

Unlike standard vinyl phonograph discs, acetates consist of a core material (usually aluminium, but glass and cardboard have also been used) coated with black nitrocellulose lacquer (prior to 1934, cellulose acetate was used as the coating, hence the common but incorrect name of acetate). They have ranged in size from 7-inches to 16-inches. Due to the metal core, acetates are heavier than standard records. Cheaper acetates may have a second hole near the centre, to prevent the disc slipping on lathes that don’t have a vacuum turntable. They are often one-sided, with no grooves on the reverse, and labels may be typed or handwritten rather than printed.

Acetates are used in record manufacturing; a master disc is created by dubbing from another medium (such as a master tape) and electroforming is then used to make negative metal moulds from. They were also used to evaluate the quality of the tape-to-disc transfer, to compare different takes or mixes of a recording, to get approval from band members, or to get preview copies to radio stations before the mass-produced copies were available.

Prior to the availability of magnetic tape, acetate discs were used for direct-to-disc recording. Home recording machines of the 1940s and 1950s used acetates.

Acetates wear much quicker than standard vinyl records due to the softer material used, and a chipped stylus can damage an acetate in one play.

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Preservation / Migration

media stability 5obsolescence 3Playback ideally requires a suitable stylus designed for use with lacquer discs, and for discs larger than 12-inches, a special turntable platter is also needed.

Graphophone / Dictaphone cylinder (1887 – early 1950s)

The Dictaphone was one of two competing wax cylinder phonograph systems for voice dictation, the other being Edison’s Ediphone system. The use of cylinders for voice recording pre-dated their use for music when, in 1887, Alexander Graham Bell, his cousin Chichester A. Bell, and Charles Sumner Tainter put into production a wax cylinder system for recording and reproducing speech (Edison then switched from tinfoil to wax cylinders in response in 1888).

Until 1907 the Dictaphone system was known as the Graphophone.

The main difference between the two rival systems was the recording method, with Edison using ‘hill and dale’ recording, while the Graphophone used lateral (side to side) recording. The cylinders could have a layer of wax shaved off, to enable re-use.

By the mid-1940s, new dictation technologies were rapidly being introduced such as Dictaphone’s own Dictabelt, Edison’s Voicewriter, the Gray Audograph and the SoundScriber, and both Edison and Dictaphone stopped supplying wax cylinders in the early 1950s.

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Picture discs (1920s – )

Picture discs are phonograph discs with images visible under the playable area.

The first types were the gramophone postcards, but the first real picture discs appeared in the 1920s. Some of these had images relevant to the music, while other promoted films the music appeared in, and others were used as propaganda. The images were often printed on thin cardboard, covered with a thin plastic coating and sound quality in most cases was poor. Some picture discs were better made, but in the 1930s the record industry suffered the effects of the depression and picture discs were a casualty.

In the 1940s, cardboard records appeared, consisting of plastic-coated card, similar to gramophone postcards. Often used in promotional campaigns, they were only intended to be played once or twice. Proper picture discs reappeared in 1946, issued on the Vogue Records label (which lasted until 1947). These had an alumuminium core, and the images were coated in a layer of vinyl providing better sound quality than the standard shellac records of the time.

From the late 1940s, children’s picture discs became popular, both in the US and Europe.

In the 1970s, LPs and singles began to appear using a new process consisting of five layers – a core of black vinyl with kiln-dried paper decals on either side and then outer skins of clear vinyl film. The first of these was Curved Air’s first album, Airconditioning, released in the UK in 1970. During the 1980s, picture disc singles were also released in unusual shapes.

Picture discs continue to be released, even though sound quality is often not as good as standard releases due in part to ultra thin outside layers of clear vinyl which supports the grooves.

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Multiple groove phonograph record (1898 – )

A multiple groove record has two or more parallel sets of grooves on one or both sides, allowing extra or hidden tracks to be added. On a disc that has multiple grooves, which track the listener hears depends on where the stylus is placed.

The first commercial record to use such a technique was a very early Berliner record released in the UK in 1898, ‘Puzzell [sic] Plate’ with two piano solos. Other early releases included ‘fortune telling’ records with different scenarios.

Later examples include the Monty Python album ‘Matching Tie and Handkerchief, issued in 1973. On early pressings, both sides were labled as ‘Side 2’, but one side had a pair of grooves.

The 12-inch single version of ‘Pop Muzik’ by M in 1979 was credited on it’s cover as the ‘first double-groove single’ as Side A and B were on one side.

Multiple groove 12-inch LPs and 12-inch singles continue to be occasionally released.

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Professional open reel tape (NAB reel) (1930s – )

Open reel tape is a magnetic tape format for audio where the tape is not enclosed in a cartridge or cassette, but held on a reel or spindle and threaded manually through the tape head assembly and attached to a take-up reel.

Magnetic tape was first developed in the 1930s in Germany, and after the war the technology was taken to America by Jack Mullin and developed commercially by Ampex with investment from Bing Crosby. The first commercial tape recorder (the Ampex Model 200) was released in 1948.

Open reel tape recorders for domestic and educational use become available by the late 1940s.

Open reel tape recorders for professional use generally use large metal reels (mostly 10½-inches) with large centre holes, which eventually become standardised and known as NAB (National Association of Broadcasters) reels, as opposed to domestic open reel tape recorders which generally used smaller plastic reels and smaller ‘cine spindle’ hubs. Tape generally runs at 15 or 30-inches per second.

Initially, tape was ¼-inches wide and used a single track. Over the years, multitrack recording become common, and by 1968, up to 24 tracks could be recorded onto 2-inch wide tape. The 2-inch 24-track tape reel became the most common format in professional recording studios throughout most of the 1970s and 1980s, but other widths (¼-inch, ½-inch and 1-inch) were also available.

Open reel tape recording was main recording format used by professional recording studios until the late 1980s when digital audio recording techniques began to allow the use of other types of media (such as Digital Audio Tape (DAT) and hard disks). Tape is still used by some recording studios, often to record digital tracks to, to effect a ‘natural’ and ‘warmer’ sound.

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Ediphone (1888 – early 1950s)

The Ediphone was one of two competing wax cylinder phonograph systems for voice dictation, the other being the Dictaphone system. The use of cylinders for voice recording pre-dated their use for music, although it wasn’t until 1888 that Edison switched from tinfoil to wax cylinders in response to the rival Graphophone system introduced in 1887 (that later became the Dictaphone system).

The main difference between the two rival systems was the recording method, with Edison using ‘hill and dale’ recording, while the Graphophone used lateral (side to side) recording. The cylinders could have a layer of wax shaved off, to enable re-use.

By around 1910, the Edison system had adopted the name Ediphone, and technical refinements were introduced over time such as electric motors, foot control pedals, and eventually electrical recording in 1939.

By the mid-1940s, new dictation technologies were rapidly being introduced such as Dictaphone’s Dictabelt, Edison’s own Voicewriter, the Gray Audograph and the SoundScriber, and both Edison and Dictaphone stopped supplying wax cylinders in the early 1950s.

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Jacquard Loom card (1801 – 1990s)

The Jacquard Loom was a mechanical loom for cloth weaving, first demonstrated by Joseph Marie Jacquard in 1801. It used a chain of punched cards laced together to allow the loom to create complex patterns.

Any number of the cards could be chained together into a continuous sequence, with each card corresponding to one row of the design. Each position on the card corresponds to a ‘Bolus’ hook which can either be raised or stopped dependent on whether the hole is punched out of the position on the card or not. The hook raises or lowers the harness, which carries and guides the warp thread so that the weft will either lie above or below it.

Modern Jacquard looms are controlled by computers in place of the original punched cards, and can have thousands of hooks.

Charles Babbage was aware of Jacquard loom cards, and planned to use cards to store programs in his Analytical engine, first described in 1837. Later in the 19th Century, Herman Hollerith used the idea of storing information on cards to create the punched card tabulating machine which he used to input data for the 1890 US Census.

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Audograph (1946 – 1976)

Audograph was a dictation disc format introduced in 1946 by the Gray Manufacturing Company in the US. It recorded sound by pressing grooves into soft vinyl discs, like the competing, but incompatible, SoundScriber and Voicewriter formats.

Audograph discs were thin plastic discs, recorded from the inside to the outside, the opposite of conventional phongraph discs. Another difference to phongraph discs was that the Audograph was driven by a surface-mounted wheel, meaning that its recording and playback speed decreased toward the edge of the disc (like the Compact Disc and other digital formats), to keep a more constant linear velocity and to improve playing time.

Along with a Dictabelt recorder, an Audograph machine captured sounds recorded at the time of the John F. Kennedy assassination that were reviewed by the United States House Select Committee on Assassinations.

Gray stopped manufacturing the Audograph in 1976.

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Photographic plate (1851 – 1990s)

Photographic plates were used in still photography and consisted of a glass plate coated with a light-sensitive emulsion of silver salts.

Photographic plates ceased to be used by amateur photographers in the early 20th century, as they switched to photographic film, but glass plates continued to be used until the 1970s by some photographic businesses, and until the 1990s for astronomical surveys before these moved to digital imaging.

Glass plates were far superior to film for research-quality imaging because they were extremely stable and less likely to bend or distort, especially in large-format frames for wide-field imaging.

Glass photographic plates using the wet collodion process, which was invented in 1851, replaced the earlier Daguerreotype process that used a polished silver coated plate of tin or copper. The wet collodion process was inconvenient and required portable darkrooms for field photography. Gelatin dry plates were first invented in 1871 and in 1878, it was discovered that heating the plates made them more resistant to friction, and the emulsion more sensitive to light. During the 1880s dry plates largely replaced wet collodion plates, although wet collodion plates continued to be used for some special purposes.

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135 film (1934 – )

135 is a photographic film format, using a single-use cartridges of 35mm film. The designation was introduced by Kodak in 1934 for use in its Kodak Retina camera, and quickly grew in popularity, surpassing formats like 120, 126110 and APS and remains popular today despite digital photography. 35mm film was used in still photography before this time, but had to be loaded by the photographer into reusable cassettes in a darkroom.

135 cameras can be loaded in daylight as the film is contained in a light-tight metal cartridge. In most cameras, the film is wound onto a spool as the film is used and rewound into the cartridge once fully exposed, but in some cameras (particularly disposable models) the film is unwound fully to begin with and exposed in reverse order so there is no need to rewind at the end.

Negative size is 36mm x 24mm, and this size is still used by digital camera image sensors. The half-frame format (18mm x 24mm) had some success in the 1960s, and some cameras have used different negative sizes.

Colour and monochrome films, negative and positive have been produced, as well as specialist films such as those sensitive to infrared radiation. Generally, the number of exposures on a 135 film are 12, 24 or 36, although until about 1980, 20 exposure films were the only films generally available with less than 36 exposures. It is often possible to get a few more exposures on a film. Since the 1980s film cassettes have been marked with a DX encoding pattern so cameras can detect the film speed. (ISO).

By the 1970s, SLR and smaller compact 135 cameras proliferated, and automated processing and printing machines made developing easier and less expensive, so quality colour prints became available from supermarkets and chemists as well as camera shops, often in less than an hour.

Despite the popularity of digital photography, 135 SLRs, compact point-and-shoot cameras, and single-use cameras continue to be built and sold, and 135 film is still readily available.

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