Akai ¼-inch open reel video tape (1969 – late 1970s)

Akai ¼-inch video tape was an analogue open reel video tape format introduced in 1969. It used helical-scanning and initially only recorded in black and white (a colour video recorder using the tape, the Akai VTS-150, was introduced in 1974).

The first machine to use the format was the Akai VTS-100, a portable video tape recorder with a detachable video monitor and a video camera. An optional RF modulator was available for playback through a standard television set.

Video resolution was 200 lines, and the system was aimed at the consumer market. One advantage over other domestic video tape recorders that used ½-inch wide tape (such as the EIAJ-1 ½-inch format) was that tape for the Akai system was much cheaper. A number of different companies produced tape for the Akai format.

Most of the tape was on plastic 5-inch reels with cine spindle hubs but the VT-700, a stationary video tape recorder introduced by Akai in the early 1970s, could accommodate 10.5-inch NAB hub reels of ¼-inch video tape as well.

Tapes recorded on the later colour VTS-150 are not compatible with tapes recorded on black and white models due to differences in tape speed.

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Centre-start phonograph record (1905 – )

Centre-start (or inside-start) phonograph records date back as far as 1905 with the Pathé vertical-cut disc record, that in addition to other unusual features such as being vertically rather than laterally cut and running at 90rpm, required the stylus to be placed in the area that on other records would be the run-out grooves. In 1915, Pathé switch to a more conventional outside-start.

Later, Electrical transcription discs (1920s – 1980s) often used centre-starts, sometimes on both sides and sometimes alternating with an outside-start on the second side, possibly to reduce changes in sound quality between the end of one side and the start of the other. As the stylus moves to the centre of a record, the linear groove speed decreases and there can be more ‘end-groove distortion’.

Since then, centre-start records have tended to be uncommon, and were usually used as a novelty or promotional feature. A couple of examples include King Kurt’s Destination Zululand 12-inch single (1983) and more recently Jack White’s Lazaretto 12-inch LP (2014), which had a centre-start on side one.

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Scotch One Five Special (1960s)

The Scotch One Five Special was a 3-inch reel of ¼-inch magnetic recording tape produced by 3M that could be recorded and played back on a standard open reel tape recorder. Once recorded, the reel would be placed back in its packaging which had space on it to write an address and to attach postage stamps to send it to someone. The tape could record for 15 minutes (hence the name) when run at 3¾-inches per second.

Similar reels marketed for keeping in touch by posting voice recordings were available around the same time, such as the Mastertape Voice Letter and the EMI Voice Letter. The Smith Corona Mail Call Letterpack of the late 1960s was a similar concept. Postage overseas was much cheaper than making an international telephone call at the time.

The One Five Special does not seem to have become very popular, and would probably have been superseded by smaller and more convenient products like the Compact Cassette.

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Mohawk Midgetape (1955 – early 1960s)

The Mohawk Midgetape was an early portable tape recorder introduced by Mohawk Business Machines in 1955 with the Midgetape 44 model.

It used a tape cassette in a metal casing with ¼-inch tape allowing 30 or 45 minutes of recording on each side of the tape. The cassette design is unusual in having the spools on top of each other (coaxial).

The is no fast forward, and rewinding is done with a fold-out handle. It came with a microphone, and had a headphone jack. Accessories included a separate amplifier, an adaptor for recording telephone conversations, a wristwatch microphone, and a leather bag with hidden microphone.

Later models were fully transistorised (the 44 had used subminiature valve tubes) and the final Midgetape model was the 500 Professional introduced in 1959. There was a also a machine based on the Midgetape called the Lafayette Transcoder that in 1961 claimed to be able to record conversation up to 30 feet away.

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Philips EL 3583 (1963 – early 1970s)

The Philips EL 3583 was an office dictation machine that used small cartridges of ⅛-inch tape. It appears to have been introduced around 1963, around the same time that Philips also introduced their Compact Cassette system, and it may have replaced the EL 3581 system.

The threading mechanism was unusual; a supply cartridge and a separate take-up cartridge would be placed in the machine and lever would be depressed causing a latch at the end of the supply cartridge’s tape to be pulled across and to lock into the take-up spool.

Like other dictation machines, the microphone also acted as a small speaker and contained a control to begin recording.

It’s unclear when the system was produced until, but it seems unlikely to be much beyond the early 1970s as Philips own Compact Cassette and mini-cassette designs, as well as other competing cassettes such as the Microcassette were available.

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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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EMI Voice Letter (1960s)

The EMI Voice Letter was a 3-inch reel of ¼-inch magnetic recording tape that could be recorded and played back on a standard open reel tape recorder. Once recorded, the reel would be placed back in its packaging which had space on it to write an address and to attach postage stamps to send it to someone. The tape could record 10 minutes when run at 3¾-inches per second.

Similar reels marketed for keeping in touch by posting voice recordings were available around the same time, such as the Mastertape Voice Letter and the Scotch One Five Special. The Smith Corona Mail Call Letterpack of the late 1960s was a similar concept. Postage overseas was much cheaper than making an international telephone call at the time.

The EMI Voice Letter does not seem to have become very popular, and would probably have been superseded by smaller and more convenient products like the Compact Cassette.

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Little LP (1961 – 1975)

The Little LP (also known as a Jukebox EP) was a 7-inch vinyl record with up to three songs on each side, that played at 33 ⅓ rpm in stereo, and had a small centre hole. They were first introduced by Cadence Records in late 1961, though the Cadence version was in mono and was not designed for jukeboxes.

The Little LP was not successful in the retail market, but it was picked up by Seeburg for use in their new jukebox, introduced in September 1962. The Seeburg version of the Little LP was in stereo, came with title strips, and had a colour cover for display in the jukebox. A number of record companies signed up, mostly easy listening and classical labels, and by 1963 there were 233 titles available with over 1,000 by 1966. Little LPs were also made for other jukebox manufacturers such as Wurlitzer and ATI.

Little LPs were essentially cut-down versions of the full 12-inch LP, and shared the same artwork. Record companies saw the potential of promoting the full LP version by having a selection of tracks available to hear, and the cover on display, in places where adult listeners gathered.

However by 1969, output of Little LPs had dropped sharply. A couple of small manufacturers revived the format in the early 1970s, but only a few titles per year were released in the period 1970-1975. Seeburg introduced new jukeboxes that didn’t play Little LPs in 1971, and the introduction of quadraphonic Little LPs didn’t make any difference as there were very few quadraphonic jukeboxes to play them on.

There were no new titles on the Little LP format for jukeboxes in 1976, but a few Little LPs have been released for the retail market as specialty items since then.

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Open reel instrumentation and data logging tape (1949 – 2000s)

Magnetic tape was first used for data logging and instrumentation recording in 1949, when Jack Mullins installed modified Ampex Model 300s at Point Mugu Naval Air Station and at Edwards Air Force Base, both in southern California.

Tape has been heavily used since then for military, industrial, government and research applications. The Inter-Range Instrumentation Group (IRIG) set the standards for instrumentation tape recorders.

Instrumentation recorders were built to much more stringent standards than other tape recorders, and recorders that used direct, FM and PCM recording have been available.

On ¼-inch wide tape, there are typically 4 tracks, whereas on ½-inch tape there were 7, or sometimes even 14, tracks. On 1-inch tape, there were 14 or 28 tracks. Tape is usually wound on the reel with the recording surface facing towards the hub (the opposite of audio tape). Metal NAB reels were often used, for reels between 10.5 and 16-inches, but 7-inch plastic reels with cine spindle hubs have also been used.

Instrumentation recorders also used tape in cassette form, including systems that recorded onto S-VHS tape, and the Digital Instrumentation Recorder from Sony that used the SD1 cassette.

Instrumentation and data logging systems now use hard disks or flash memory for storage.

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