Early history
A device utilizing a vibrating pen to graphically represent sound on discs of paper, without the idea of playing it back in any manner, was described by Charles Cros of France in 1877, but never built. In 1877, Thomas Edison independently built the first working phonograph, a tinfoil cylinder machine, intending to use it as a voice recording medium, typically for office dictation. This phonograph cylinder dominated the recorded sound market beginning in the 1880s. Lateral-cut disc records were invented by Emile Berliner in 1888 and were used exclusively in toys until 1894, when Berliner began marketing disc records under the Berliner Gramophone label. The Edison "Blue Amberol" cylinder was introduced in 1912, with a longer playing time of around 4 minutes (at 160 rpm) and a more resilient playing surface than its wax predecessor, but the format was doomed due to the difficulty of reproducing recordings. By November 1918 the patents for the manufacture of lateral-cut disc records expired, opening the field for countless companies to produce them, causing disc records to overtake cylinders in popularity. Production of Amberol cylinders ceased in the late 1920s. Disc records would dominate the market until they were supplanted by the Compact Disc, starting from the 1980s.
Materials
Early disc records were made of various materials including hard rubber. From 1897 onwards, earlier materials were largely replaced by a rather brittle formula of 25% "shellac" (a material obtained from the secretion of a southeast Asian beetle), a filler of a cotton compound similar to manila paper, powdered slate, and a small amount of a wax lubricant. The mass production of shellac records began in 1898 in Hanover, Germany. Shellac records were the most common until the 1950s. "Unbreakable" records, usually of celluloid (an early form of plastic) on a pasteboard base, were made from 1904 onwards, but they suffered from an exceptionally high level of surface noise. "Unbreakable" records could be bent, broken, or otherwise damaged; but not nearly as easily as the "breakable" records.
In the 1890s the early recording formats of discs were usually seven inches (nominally 17.5 cm) in diameter. By 1910 the 10-inch (25.4cm) record was by far the most popular standard, holding about three minutes of music or entertainment on a side. From 1903 onwards, 12-inch records (30.5cm) were also commercially sold, mostly of classical music or operatic selections, with four to five minutes of music per side.
Such records were usually sold separately, in plain paper or cardboard sleeves that may have been printed to show the producer or the retailer's name and, starting in the 1930s, in collections held in paper sleeves in a cardboard or leather book, similar to a photograph album, and called record albums. Empty record albums were also sold that customers could use to store their records in.
While a 78 rpm record is brittle and relatively easily broken, both the microgroove LP 33⅓ rpm record and the 45 rpm single records are made from vinyl plastic that is flexible and unbreakable in normal use. However, the vinyl records are easier to scratch or gouge, and much more prone to warpage. 78s come in a variety of sizes, the most common being 10 inches (25 cm), and 12 inches (30 cm) in diameter (sometimes 6–8 inches in the UK), and these were originally sold in either paper or card covers, generally with a circular cutout allowing the record label to be seen. The Long-Playing records (LPs) usually come in a paper sleeve within a color printed card jacket which also provides a track listing. 45 rpm singles and EPs (Extended Play) are of a 7-inch (17.5 cm) diameter, the earlier copies being sold in paper covers.
In 1930, RCA Victor launched the first commercially available vinyl long-playing record, marketed as "Program Transcription" discs. These revolutionary discs were designed for playback at 33⅓ rpm and pressed on a 30 cm diameter flexible plastic disc. In Roland Gelatt's book The Fabulous Phonograph, the author notes that RCA Victor's early introduction of a long-play disc was a commercial failure for several reasons including the lack of affordable, reliable consumer playback equipment and consumer wariness during the Great Depression.[1]
However, vinyl's lower surface noise level than shellac was not forgotten, nor was its durability. In the late 30's, radio commercials and prerecorded radio programs being sent to disc jockeys started being stamped in vinyl, so they would not break in the mail. In the mid-40's, special DJ copies of records started being made of vinyl also, for the same reason. These were all 78 RPM. During and after World War II when shellac supplies were extremely limited, some 78 rpm records were pressed in vinyl instead of shellac, particularly the six-minute 12" (30 cm) 78 rpm records produced by V-Disc for distribution to US troops in World War II. In the 40's, radio transcriptions, which were usually on 16 inch records, but sometimes 12 inch, were always made of vinyl, but cut at 33 1/3 rpm. Shorter transcriptions were often cut at 78 rpm.
Beginning in 1939, Columbia Records continued development of this technology. Dr. Peter Goldmark and his staff undertook exhaustive efforts to address problems of recording and playing back narrow grooves and developing an inexpensive, reliable consumer playback system. In 1948, the 12" (30 cm) Long Play (LP) 33⅓ rpm microgroove record album was introduced by the Columbia Record Company at a dramatic New York press conference. In 1949, RCA Victor released the first 45 RPM single, 7" in diameter, with a large center hole to accommodate an automatic play mechanism on the changer, so a stack of singles would drop down one record at a time automatically after each play. Early 45 RPM records were made from either vinyl or polystyrene.
On a small number of early phonograph systems and radio transcription discs, as well as some entire albums, such as Goodbye Blue and White by Less Than Jake, the direction of the groove is reversed, beginning near the centre of the disc and leading to the outside. A small number of records (such as Jeff Mills' Apollo EP or the Hidden In Plainsight EP from Detroit's Underground Resistance) were manufactured with multiple separate grooves to differentiate the tracks (usually called 'NSC-X2'). X2 was pioneered by Ron Murphy and Heath Brunner from Sound Enterprises (formerly National Sound Corporation), a record mastering company in Detroit.
Speeds
The earliest rotation speeds varied widely. Most records made in 1900–1925 were recorded at 74–82 revolutions per minute (RPM). However a few unusual systems were deployed. The Dutch Philips company introduced records whose rotational speed varied such that the reproducing "needle" ran at a constant linear velocity (CLV) in the groove. These records also, unusually, played from the inside to the outside. Both of these features were to be emulated by the modern day Compact Disc. The London Science Museum displays a Philips CLV record marked as "Speed D".
In 1925, 78.26 rpm was chosen as the standard because of the introduction of the electrically powered synchronous turntable motor. This motor ran at 3600 rpm with a 46:1 gear ratio which produced 78.26 rpm. In parts of the world that used 50 Hz current, the standard was 77.92 RPM (3000 rpm with a 38.5:1 ratio), which was also the speed at which a strobe disc with 77 lines would "stand still" in 50 Hz light (92 lines for 60Hz). Thus these records became known as 78s (or "seventy-eights"). This term did not come into use until after World War II when a need developed to distinguish the 78 from other newer disc record formats, an example of a retronym. Earlier they were just called records, or when there was a need to distinguish them from cylinders, disc records. Standard records was also used, although the same term had also been used earlier for two-minute cylinders.
After World War II, two new competing formats came on to the market and gradually replaced the standard "78": the 33⅓ rpm (often just referred to as the 33 rpm), and the 45 rpm. The 33⅓ rpm LP (for "long play") format was developed by Columbia Records and marketed in 1948. RCA Victor developed the 45 rpm format and marketed it in 1949, in response to Columbia. Both types of new disc used narrower grooves, intended to be played with a smaller stylus—typically 0.001" (25 µm) wide, compared to 0.003" (76 µm) for a 78—so the new records were sometimes called Microgroove. In the mid-1950s all record companies agreed to a common recording standard called RIAA equalization. Prior to the establishment of the standard each company used its own preferred standard, requiring discriminating listeners to use preamplifiers with multiple selectable equalization curves.
A number of recordings were pressed at 16⅔ RPM (usually a 7" disc, visually identical to a 45 RPM single), but these were mostly used for radio transcription discs or narrated publications for the blind and visually impaired, and were never widely commercially available, although it was common to see turntables with a 16 RPM speed setting produced as late as the 1970s.
The older 78 format continued to be mass produced alongside the newer formats into the 1950s, and in a few countries, such as India, into the 1960s. As late as the 1970s, some children's records were released at the 78 rpm speed.
The commercial rivalry between RCA Victor and Columbia Records led to RCA Victor's introduction of what it had intended to be a competing vinyl format, the 7" (175 mm) /45 rpm disc. For a two-year period from 1948 to 1950, record companies and consumers faced uncertainty over which of these formats would ultimately prevail in what was known as the "War of the Speeds". (See also format war.)
Eventually the 12" (300 mm) 33⅓ rpm LP prevailed as the predominant format for musical albums, and the 7" (175 mm) 45 rpm disc or "single" established a significant niche for shorter duration discs, typically containing one song on each side. The 45 rpm discs typically emulated the playing time of the former 78 rpm discs, while the LP discs provided up to one half hour of time per side (though typically 15 to 20 minutes). The 45 rpm discs also came in a variety known as Extended play (EP) which achieved up to 10-15 minutes play at the expense of attenuating (and possibly compressing) the sound to reduce the width required by the groove.
From the mid-1950s through the 1960s, in the U.S. the common home "record player" or "stereo" would typically have had these features: a three- or four-speed player with changer (78, 45, 33⅓, and sometimes 16⅔ rpm); a combination cartridge with both 78 and microgroove styluses; and some kind of adapter for playing the 45s with their larger center hole. The large center hole on 45s allows for easier handling by jukebox mechanisms.
RCA 45s were also adapted to the smaller spindle of an LP player with a plastic snap-in insert known as a "spider". These inserts, commissioned by RCA president David Sarnoff and invented by Thomas Hutchison, were prevalent starting in the 1960s, selling in the tens of millions per year during the 45's heyday.
Deliberately playing or recording records at the wrong speed was a common amusement. Playing at a higher speed gave an antic quirkiness to voices whereas playing at a slower speed changed music and voice to an ominous, growling tone.
This effect was used in 1966 by Cork Marcheschi of California group the Ethix (and later of Fifty Foot Hose), who issued an experimental single, "Bad Trip", which could be played at any speed. Canadian musician Nash the Slash also took advantage of this speed/tonal effect with his 1981 12" disc Decomposing, which featured four instrumental tracks that were engineered to play at any speed (with the playing times listed for 33⅓, 45 and 78 rpm playback). Faster playback made the tracks sound like punk rock or power pop, while slower speeds gave the songs a thick, heavy metal effect.
Music from a 33⅓ rpm LP of the animated musical group Alvin and the Chipmunks can be played at 16 rpm to reveal how male voices singing very slowly are used to produce the high pitched rodents' voices apparently singing the song at normal speed.
Sound enhancements
In 1958 the first stereo two-channel records were issued—by Audio Fidelity in the USA and Pye in Britain, using the Westrex "45/45" single-groove system. While the stylus moves horizontally when reproducing a monophonic disk recording, on stereo records the stylus moves vertically as well as horizontally.
One could envision a system in which the left channel was recorded laterally, as on a monophonic recording, with the right channel information recorded with a "hill-and-dale" vertical motion; such systems were proposed but not adopted, due to their incompatibility with existing phono pickup designs (see below). In the Westrex system, each channel drives the cutting head at a 45 degree angle to the vertical. During playback the combined signal is sensed by a left channel coil mounted diagonally opposite the inner side of the groove, and a right channel coil mounted diagonally opposite the outer side of the groove.[2]
It is helpful to think of the combined stylus motion in terms of the vector sum and difference of the two stereo channels. Effectively, all horizontal stylus motion conveys the L+R sum signal, and vertical stylus motion carries the L-R difference signal. The advantages of the 45/45 system are:
- greater compatibility with monophonic recording and playback systems. A monophonic cartridge will reproduce an equal blend of the left and right channels instead of reproducing only one channel. (However many monophonic cartridges would damage a stereo groove, leading to the common recommendation to never use a mono cartridge on a stereo record.) Conversely, a stereo cartridge reproduces the lateral grooves of monophonic recording equally through both channels, rather than one channel.
- a more balanced sound, because the two channels have equal fidelity (rather than providing one higher-fidelity laterally recorded channel and one lower-fidelity vertically recorded channel);
- higher fidelity in general, because the "difference" signal is usually of low power and thus less affected by the intrinsic distortion of hill-and-dale recording.
This system was invented by Alan Blumlein of EMI in 1931 and patented the same year. EMI cut the first stereo test discs using the system in 1933. It was not used commercially until a quarter of a century later.
Stereo sound provides a more natural listening experience where the spatial location of the source of a sound is, at least in part, reproduced.
Under the direction of C. Robert Fine, Mercury Records initiated a minimalist single microphone monaural recording technique in 1951. The first record, Kubelik/Chicago's performance of "Pictures at an Exhibition" was described as "being in the living presence of the orchestra" by The New York Times music critic. The series of records was then named “Mercury Living Presence”. In 1955 Mercury began three-channel stereo recordings, still based on the principle of the single microphone. The center (single) microphone was of paramount importance, with the two side mics adding depth and space. Record masters were cut directly from a three-track to two-track mixdown console, with all editing of the master tapes done on the original three-tracks. In 1961 Mercury enhanced this technique with three-microphone stereo recordings using 35mm magnetic film instead of half-inch tape for recording. The greater thickness and width of 35mm magnetic film prevented tape layer print-through and pre-echo and gained extended frequency range and transient response. The Mercury Living Presence recordings were remastered to CD in the 1990s by the original producer, using the same method of 3-to-2 mix directly to the master recorder.
The development of quadraphonic records was announced in 1971. These recorded four separate sound signals. This was achieved on the two stereo channels by electronic matrixing, where the additional channels were combined into the main signal. When the records were played, phase-detection circuits in the amplifiers were able to decode the signals into four separate channels. There were two main systems of matrixed quadraphonic records produced, confusingly named SQ (by CBS) and QS (by Sansui). They proved commercially unsuccessful, but were an important precursor to later "surround sound" systems, as seen in SACD and home cinema today. A different format, CD-4 (not to be confused with compact disc), by RCA, encoded rear channel information on an ultrasonic carrier, which required a special wideband cartridge to capture it on carefully-calibrated pickup arm/turntable combinations. Typically the high frequency information inscribed onto these LPs wore off after only a few playings, and CD-4 was even less successful than the two matrixed formats.
In the late 1970s and 1980s, a method to improve the dynamic range of mass produced records involved highly advanced disc cutting equipment. These techniques, marketed as the CBS DisComputer and Teldec Direct Metal Mastering, were used to reduce inner-groove distortion. RCA Victor introduced another system to boost dynamic range and achieve a groove with less surface noise under the commercial name of Dynagroove. Two main elements were combined: another disk material with less surface noise in the groove and dynamic expansion for masking background noise. Sometimes this was called "diaphragming" the source material and not favoured by some music lovers for its unnatural side effects. Both elements were reflected in the brandname of Dynagroove, described elsewhere in more detail. Furthermore it used advanced forward looking steering on track distance with respect to volume of sound and position on the disk. Tracks were close to each other with lower volumes and farther away with loud passages. Also the higher track density at lower volumes enabled disk recordings to end farther away from the inner circle than usual, helping to reduce endtrack distorsion even further.
Also in the late 1970s, "direct-to-disc" records were produced, aimed at an audiophile niche market. These completely bypassed the use of magnetic tape in favor of a "purist" transcription directly to the master lacquer disc. Also during this period, "half-speed mastered" and "original master" records were released, using expensive state-of-the-art technology. A further late 1970s development was the Disco Eye-Cued(TM) system used mainly on Motown 12" singles released between 1978 and 1980. The introduction, drum-breaks or choruses of a track were indicated by widely separated grooves, giving a visual clue to DJs mixing the records. The appearance of these records is similar to an LP, but they only contain one track each side.
The early 1980s saw the introduction of "dbx-encoded" records, again for the audiophile niche market. These were completely incompatible with standard record playback preamplifiers, relying on the dbx compandor encoding/decoding scheme to greatly increase dynamic range (dbx encoded disks were recorded with the dynamic range compressed by a factor of two in dB: quiet sounds were meant to be played back at low gain and loud sounds were meant to be played back at high gain, via automatic gain control in the playback equipment; this reduced the effect of surface noise on quiet passages). A similar and very short lived scheme involved using the CBS-developed "CX" noise reduction encoding/decoding scheme.
ELPJ, a Japanese-based company, has developed a player that uses a laser instead of a stylus to read vinyl discs. In theory the laser turntable eliminates the possibility of scratches and attendant degradation of the sound, but its expense limits use primarily to digital archiving of analog records. Various other laser-based turntables were tried during the 1990s, but while a laser reads the groove very accurately, since it does not touch the record, the dust that vinyl naturally attracts due to static charge is not cleaned from the groove, worsening sound quality in casual use compared to conventional stylus playback.
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