Gramophone record

	78 rpm video Video of a 1936 spring-motor-driven 78 rpm acoustic (non-electronic) gramophone
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A gramophone record (phonograph record in the US), commonly known as a vinyl record or simply vinyl or record, is an analog sound storage medium in the form of a flat polyvinyl chloride (previously shellac) disc with an inscribed, modulated spiral groove. The groove usually starts near the periphery and ends near the center of the disc.

The phonograph disc record was the primary medium used for music reproduction until late in the 20th century. It had co-existed with the phonograph cylinder from the late 1880s and replaced it by the late 1920s. Records retained the largest market share even when new formats such as compact cassette were mass-marketed. By the late 1980s, digital media, in the form of the compact disc, had gained a larger market share, and the vinyl record left the mainstream in 1991.^[1] From the 1990s to the 2010s, records continued to be manufactured and sold on a much smaller scale, and were especially used by disc jockeys (DJs), released by artists in some genres, and listened to by a niche market of audiophiles. The phonograph record has made a niche resurgence in the early 21st century – 9.2 million records were sold in the U.S. in 2014, a 260% increase since 2009.^[2] Likewise, in the UK sales have increased five-fold from 2009 to 2014.^[3]

As of 2017, 48 record pressing facilities remain worldwide, 18 in the United States and 30 in other countries. The increased popularity of vinyl has led to the investment in new and modern record-pressing machines.^[4] Only two producers of lacquers remain: Apollo Masters in California, USA, and MDC in Japan.^[5]

Phonograph records are generally described by their diameter in inches (12-inch, 10-inch, 7-inch), the rotational speed in revolutions per minute (rpm) at which they are played ( 8 ¹⁄₃,  16 ²⁄₃,  33 ¹⁄₃, 45, 78),^[6] and their time capacity, determined by their diameter and speed (LP [long playing], 12-inch disc,  33 ¹⁄₃ rpm; SP [single], 10-inch disc, 78 rpm, or 7-inch disc, 45 rpm; EP [extended play], 12-inch disc,  33 ¹⁄₃ or 45 rpm); their reproductive quality, or level of fidelity (high-fidelity, orthophonic, full-range, etc.); and the number of audio channels (mono, stereo, quad, etc.).

Vinyl records may be scratched or warped if stored incorrectly but if they are not exposed to high heat or broken, a vinyl record has the potential to last for centuries.

The large cover (and inner sleeves) are valued by collectors and artists for the space given for visual expression, especially when it comes to the long play vinyl LP.

Early history

The phonautograph, patented by Léon Scott in 1857, used a vibrating diaphragm and stylus to graphically record sound waves as tracings on sheets of paper, purely for visual analysis and without any intent of playing them back. In the 2000s, these tracings were first scanned by audio engineers and digitally converted into audible sound. Phonautograms of singing and speech made by Scott in 1860 were played back as sound for the first time in 2008. Along with a tuning fork tone and unintelligible snippets recorded as early as 1857, these are the earliest known recordings of sound.

In 1877, Thomas Edison invented the phonograph. Unlike the phonautograph, it was capable of both recording and reproducing sound. Despite the similarity of name, there is no documentary evidence that Edison's phonograph was based on Scott's phonautograph. Edison first tried recording sound on a wax-impregnated paper tape, with the idea of creating a "telephone repeater" analogous to the telegraph repeater he had been working on. Although the visible results made him confident that sound could be physically recorded and reproduced, his notes do not indicate that he actually reproduced sound before his first experiment in which he used tinfoil as a recording medium several months later. The tinfoil was wrapped around a grooved metal cylinder and a sound-vibrated stylus indented the tinfoil while the cylinder was rotated. The recording could be played back immediately. The Scientific American article that introduced the tinfoil phonograph to the public mentioned Marey, Rosapelly and Barlow as well as Scott as creators of devices for recording but, importantly, not reproducing sound.^[7] Edison also invented variations of the phonograph that used tape and disc formats.^[8] Numerous applications for the phonograph were envisioned, but although it enjoyed a brief vogue as a startling novelty at public demonstrations, the tinfoil phonograph proved too crude to be put to any practical use. A decade later, Edison developed a greatly improved phonograph that used a hollow wax cylinder instead of a foil sheet. This proved to be both a better-sounding and far more useful and durable device. The wax phonograph cylinder created the recorded sound market at the end of the 1880s and dominated it through the early years of the 20th century.

Lateral-cut disc records were developed in the United States by Emile Berliner, who named his system the "gramophone", distinguishing it from Edison's wax cylinder "phonograph" and Columbia's wax cylinder "graphophone". Berliner's earliest discs, first marketed in 1889, but only in Europe, were 12.5 cm (approx 5 inches) in diameter, and were played with a small hand-propelled machine. Both the records and the machine were adequate only for use as a toy or curiosity, due to the limited sound quality. In the United States in 1894, under the Berliner Gramophone trademark, Berliner started marketing records of 7 inches diameter with somewhat more substantial entertainment value, along with somewhat more substantial gramophones to play them. Berliner's records had poor sound quality compared to wax cylinders, but his manufacturing associate Eldridge R. Johnson eventually improved the sound quality. Abandoning Berliner's "Gramophone" trademark for legal reasons, in 1901 Johnson's and Berliner's separate companies reorganized to form the Victor Talking Machine Company, whose products would come to dominate the market for many years.^[9] Emile Berliner moved his company to Montreal in 1900. The factory, which became the Canadian branch of RCA Victor still exists. There is a dedicated museum in Montreal for Berliner.

In 1901, 10-inch disc records were introduced, followed in 1903 by 12-inch records. These could play for more than three and four minutes respectively, whereas contemporary cylinders could only play for about two minutes. In an attempt to head off the disc advantage, Edison introduced the Amberol cylinder in 1909, with a maximum playing time of 4½ minutes (at 160 rpm), which in turn were superseded by Blue Amberol Records, which had a playing surface made of celluloid, a plastic, which was far less fragile. Despite these improvements, during the 1910s discs decisively won this early format war, although Edison continued to produce new Blue Amberol cylinders for an ever-dwindling customer base until late in 1929. By 1919 the basic patents for the manufacture of lateral-cut disc records had expired, opening the field for countless companies to produce them. Analog disc records would dominate the home entertainment market until they were outsold by the digital compact disc in the late 1980s (which was in turn supplanted by digital audio recordings distributed via online music stores and Internet file sharing).

78 rpm disc developments

Early speeds

Early disc recordings were produced in a variety of speeds ranging from 60 to 130 rpm, and a variety of sizes. As early as 1894, Emile Berliner's United States Gramophone Company was selling single-sided 7-inch discs with an advertised standard speed of "about 70 rpm".^[10]

One standard audio recording handbook describes speed regulators, or governors, as being part of a wave of improvement introduced rapidly after 1897. A picture of a hand-cranked 1898 Berliner Gramophone shows a governor. It says that spring drives replaced hand drives. It notes that:

The speed regulator was furnished with an indicator that showed the speed when the machine was running so that the records, on reproduction, could be revolved at exactly the same speed...The literature does not disclose why 78 rpm was chosen for the phonograph industry, apparently this just happened to be the speed created by one of the early machines and, for no other reason continued to be used.^[11]

By 1925, the speed of the record was becoming standardized at a nominal value of 78 rpm. However, the standard differed between places with alternating current electricity supply at 60 hertz (cycles per second, Hz) and those at 50 Hz. Where the mains supply was 60 Hz, the actual speed was 78.26 rpm: that of a 60 Hz stroboscope illuminating 92-bar calibration markings. Where it was 50 Hz, it was 77.92 rpm: that of a 50 Hz stroboscope illuminating 77-bar calibration markings.^[12]

Acoustic recording

Early recordings were made entirely acoustically, the sound being collected by a horn and piped to a diaphragm, which vibrated the cutting stylus. Sensitivity and frequency range were poor, and frequency response was very irregular, giving acoustic recordings an instantly recognizable tonal quality. A singer practically had to put his or her face in the recording horn. Lower-pitched orchestral instruments such as cellos and double basses were often doubled (or replaced) by louder instruments, such as tubas. Standard violins in orchestral ensembles were commonly replaced by Stroh violins, which became popular with recording studios.

Contrary to popular belief, if placed properly and prepared-for, drums could be effectively used and heard on even the earliest jazz and military band recordings. The loudest instruments such as the drums and trumpets were positioned the farthest away from the collecting horn. Lillian Hardin Armstrong, a member of King Oliver's Creole Jazz Band, which recorded at Gennett Records in 1923, remembered that at first Oliver and his young second trumpet, Louis Armstrong, stood next to each other and Oliver's horn could not be heard. "They put Louis about fifteen feet over in the corner, looking all sad."^[13][14]

Electrical recording

During the first half of the 1920s, engineers at Western Electric, as well as independent inventors such as Orlando Marsh, developed technology for capturing sound with a microphone, amplifying it with vacuum tubes, then using the amplified signal to drive an electromechanical recording head. Western Electric's innovations resulted in a greatly expanded and more even frequency response, creating a dramatically fuller, clearer and more natural-sounding recording. Distant or less strong sounds that were impossible to record by the old methods could now be captured. Volume was now limited only by the groove spacing on the record and the limitations of the intended playback device. Victor and Columbia licensed the new electrical system from Western Electric and began issuing electrically recorded discs during the Spring of 1925. The first classical recording was of Chopin impromptus and Schubert's Litanei by Alfred Cortot for Victor.^[15]

A 1926 Wanamaker's ad in The New York Times offers records "by the latest Victor process of electrical recording".^[16] It was recognized as a breakthrough; in 1930, a Times music critic stated:

... the time has come for serious musical criticism to take account of performances of great music reproduced by means of the records. To claim that the records have succeeded in exact and complete reproduction of all details of symphonic or operatic performances ... would be extravagant ... [but] the article of today is so far in advance of the old machines as hardly to admit classification under the same name. Electrical recording and reproduction have combined to retain vitality and color in recitals by proxy.^[17]

Electrical recording preceded electrical home reproduction because of the initial high cost of the new system. In 1925, the Victor company introduced the Orthophonic Victrola, an acoustical record player that was specifically designed to play electrically recorded discs, as part of a line that also included electrically reproducing Electrolas. The acoustical Orthophonics ranged in price from US$95 to US$300, depending on cabinetry; by comparison, the cheapest Electrola cost US$650, the price of a new car in an era when clerical jobs paid about $20 a week.

The Orthophonic had an interior folded exponential horn, a sophisticated design informed by impedance-matching and transmission-line theory, and designed to provide a relatively flat frequency response. Its first public demonstration was front-page news in The New York Times, which reported:

The audience broke into applause ... John Philip Sousa [said]: '[Gentlemen], that is a band. This is the first time I have ever heard music with any soul to it produced by a mechanical talking machine' ... The new instrument is a feat of mathematics and physics. It is not the result of innumerable experiments, but was worked out on paper in advance of being built in the laboratory ... The new machine has a range of from 100 to 5,000 [cycles], or five and a half octaves ... The 'phonograph tone' is eliminated by the new recording and reproducing process.^[18]

Gradually, electrical reproduction entered the home. The spring motor was replaced by an electric motor. The old sound box with its needle-linked diaphragm was replaced by an electromagnetic pickup that converted the needle vibrations into an electrical signal. The tone arm now served to conduct a pair of wires, not sound waves, into the cabinet. The exponential horn was replaced by an amplifier and a loudspeaker.

The Great Depression of the 1930s nearly killed the phonograph industry. RCA, which bought the Victor Talking Machine Company in 1929, introduced an inexpensive turntable called the Duo Jr., which was designed to be connected to radio sets.^[19]

78 rpm materials

The earliest disc records (1889–1894) were made of various materials including hard rubber. Around 1895, a shellac-based compound was introduced and became standard. Exact formulas for this compound varied by manufacturer and over the course of time, but it was typically composed of about one-third shellac and about two-thirds mineral filler, which meant finely pulverized rock, usually slate and limestone, with an admixture of cotton fibers to add tensile strength, carbon black for color (without this, it tended to be a "dirty" gray or brown color that most record companies considered unattractive), and a very small amount of a lubricant to facilitate mold release during manufacture. Some makers, notably Columbia Records, used a laminated construction with a core disc of coarser material or fiber. The production of shellac records continued until the end of the 78 rpm format (i.e., the late 1950s in most developed countries, but well into the 1960s in some other places), but increasingly less abrasive formulations were used during its declining years and very late examples in truly like-new condition can have as low noise levels as vinyl.

Flexible or so-called "unbreakable" records made of unusual materials were introduced by a number of manufacturers at various times during the 78 rpm era. In the UK, Nicole records, made of celluloid or a similar substance coated onto a cardboard core disc, were produced for a few years beginning in 1904, but they suffered from an exceptionally high level of surface noise. In the United States, Columbia Records introduced flexible, fiber-cored "Marconi Velvet Tone Record" pressings in 1907, but the advantages and longevity of their relatively noiseless surfaces depended on the scrupulous use of special gold-plated Marconi Needles and the product was not a success. Thin, flexible plastic records such as the German Phonycord and the British Filmophone and Goodson records appeared around 1930 but also did not last long. The contemporary French Pathé Cellodiscs, made of a very thin black plastic, which uncannily resembles the vinyl "sound sheet" magazine inserts of the 1965–1985 era, were similarly short-lived. In the US, Hit of the Week records, made of a patented translucent plastic called Durium coated on a heavy brown paper base, were introduced in early 1930. A new issue came out every week and they were sold at newsstands like a weekly magazine. Although inexpensive and commercially successful at first, they soon fell victim to the Great Depression and production in the US ended in 1932. Related Durium records continued to be made somewhat later in the UK and elsewhere, and as remarkably late as 1950 in Italy, where the name "Durium" survived far into the LP era as a trademark on ordinary vinyl records. Despite all these attempts at innovation, shellac compounds continued to be used for the overwhelming majority of commercial 78 rpm records during the lifetime of the format.

In 1931, RCA Victor introduced their vinyl-based Victrolac compound as a material for some unusual-format and special-purpose records. One such was a 16-inch,  33 ¹⁄₃ RPM record used by the Vitaphone sound-on-disc movie system. In 1932, RCA began using Victrolac in their "home recording" system, with which people could record their own voices at home. By the end of the 1930s vinyl's advantages of light weight, relative unbreakability, and low surface noise had made it the material of choice for prerecorded radio programming and other critical applications. When it came to ordinary 78 rpm records, however, the much higher cost of the raw material, as well as its vulnerability to the heavy pickups and crudely mass-produced steel needles still commonly used in home record players, made its general substitution for shellac impractical at that time. During the Second World War, the United States Armed Forces produced thousands of 12-inch vinyl 78 rpm V-Discs for use by the troops overseas.^[20] After the war, the wider use of vinyl became more practical as new record players with relatively lightweight crystal pickups and precision-ground styli made of sapphire or an exotic osmium alloy proliferated. In late 1945, RCA Victor began offering special transparent red vinyl De Luxe pressings of some Red Seal classical 78s, at a De luxe price. Later, Decca Records introduced vinyl Deccalite 78s, while other record companies came up with vinyl concoctions such as Metrolite, Merco Plastic, and Sav-o-flex, but these were mainly used to produce "unbreakable" children's records and special thin vinyl DJ pressings for shipment to radio stations.^[21]

78 rpm disc size

In the 1890s, the recording formats of the earliest (toy) discs were mainly 12.5 cm (nominally 5 inches) in diameter; by the mid-1890s, the discs were usually 7 inches (nominally 17.5 cm) in diameter.

By 1910, the 10-inch (25.4 cm) record was by far the most popular standard, holding about 3 minutes (180 s) of music or other entertainment on a side.

From 1903 onwards, 12-inch records (30.5 cm) were also sold commercially, mostly of classical music or operatic selections, with 4 to 5 minutes (240 to 300 s) of music per side. Victor, Brunswick and Columbia also issued 12-inch popular medleys, usually spotlighting a Broadway show score.

Other sizes also appeared. Eight-inch (20 cm) discs with a 2-inch-diameter (51 mm) label became popular for about a decade in Britain, but they cannot be played in full on most modern record players, since the tone arm cannot play far enough in toward the center without modification of the equipment.

78 rpm recording time

The playing time of a phonograph record depended on the turntable speed and the groove spacing. At the beginning of the 20th century, the early discs played for two minutes, the same as early cylinder records.^[22] The 12-inch disc, introduced by Victor in 1903, increased the playing time to three and a half minutes.^[23] Because a 10-inch 78 rpm record could hold about three minutes of sound per side and the 10-inch size was the standard size for popular music, almost all popular recordings were limited to around three minutes in length.^[24] For example, when King Oliver's Creole Jazz Band, including Louis Armstrong on his first recordings, recorded 13 sides at Gennett Records in Richmond, Indiana, in 1923, one side was 2:09 and four sides were 2:52–2:59.^[25]

In January 1938, Milt Gabler started recording for his new label, Commodore Records, and to allow for longer continuous performances, he recorded some 12-inch records. Eddie Condon explained: "Gabler realized that a jam session needs room for development." The first two 12-inch recordings did not take advantage of the extra length: "Carnegie Drag" was 3:15; "Carnegie Jump", 2:41. But at the second session, on April 30, the two 12-inch recordings were longer: "Embraceable You" was 4:05; "Serenade to a Shylock", 4:32.^[26][27] Another way around the time limitation was to issue a selection on both sides of a single record. Vaudeville stars Gallagher and Shean recorded "Mr. Gallagher and Mr. Shean", written by Irving and Jack Kaufman, as two sides of a 10-inch 78 in 1922 for Cameo.^[28] An obvious workaround for longer recordings was to release a set of records. An early multi-record release was in 1903, when HMV in England made the first complete recording of an opera, Verdi's Ernani, on 40 single-sided discs.^[29] In 1940, Commodore released Eddie Condon and his Band's recording of "A Good Man Is Hard to Find" in four parts, issued on both sides of two 12-inch 78s. This limitation on the duration of recordings persisted from 1910 until the invention of the LP record, in 1948. In popular music, this time limitation of about 3:30 on a 10-inch 78 rpm record meant that singers usually did not release long pieces on record. One exception is Frank Sinatra's recording of Rodgers and Hammerstein's "Soliloquy", from Carousel, made on May 28, 1946. Because it ran 7:57, longer than both sides of a standard 78 rpm 10-inch record, it was released on Columbia's Masterwork label (the classical division) as two sides of a 12-inch record.^[30] The same was true of John Raitt's performance of the song on the original cast album of Carousel, which had been issued on a 78-rpm album set by American Decca in 1945.

In the 78 era, classical-music and spoken-word items generally were released on the longer 12-inch 78s, about 4–5 minutes per side. For example, on June 10, 1924, four months after the February 12 premier of Rhapsody in Blue, George Gershwin recorded a drastically shortened version of the seventeen-minute work with Paul Whiteman and His Orchestra. It was released on two sides of Victor 55225 and ran for 8:59.^[31]

Record albums

Such 78 rpm records were usually sold separately, in brown paper or cardboard sleeves that were sometimes plain and sometimes printed to show the producer or the retailer's name. Generally the sleeves had a circular cut-out allowing the record label to be seen. Records could be laid on a shelf horizontally or stood upright on an edge, but because of their fragility, many broke in storage.

German record company Odeon is often said to have pioneered the album in 1909 when it released the Nutcracker Suite by Tchaikovsky on 4 double-sided discs in a specially designed package.^[29] (It is not indicated what size the records are.) However, Deutsche Grammophon had produced an album for its complete recording of the opera Carmen in the previous year. The practice of issuing albums does not seem to have been widely taken up by other record companies for many years; however, HMV provided an album, with a pictorial cover, for the 1917 recording of The Mikado (Gilbert & Sullivan).

By about 1910,^{[note 1]} bound collections of empty sleeves with a paperboard or leather cover, similar to a photograph album, were sold as record albums that customers could use to store their records (the term "record album" was printed on some covers). These albums came in both 10-inch and 12-inch sizes. The covers of these bound books were wider and taller than the records inside, allowing the record album to be placed on a shelf upright, like a book, suspending the fragile records above the shelf and protecting them.

In the 1930s, record companies began issuing collections of 78 rpm records by one performer or of one type of music in specially assembled albums, typically with artwork on the front cover and liner notes on the back or inside cover. Most albums included three or four records, with two sides each, making six or eight tunes per album. When the 12-inch vinyl LP era began in 1949, the single record often had the same or similar number of tunes as a typical album of 78s, and was still often referred to as an "album", as they still are today.

78 rpm releases in the microgroove era

For collectible or nostalgia purposes, or for the benefit of higher-quality audio playback provided by the 78 rpm speed with newer vinyl records and their lightweight stylus pickups, a small number of 78 rpm records have been released since the major labels ceased production. The most notable attempt at this was in 1951, when inventor Ewing Dunbar Nunn founded the label Audiophile Records, which released a series of 78 rpm-mastered albums that were microgroove and pressed on vinyl (as opposed to traditional 78s, with their shellac composition and wider 3-mil sized grooves). This series came in heavy manilla envelopes and began with a jazz album AP-1 and was soon followed by other AP numbers up through about AP-19. Around 1953 the standard LP had proven itself to Nunn and he switched to  33 ¹⁄₃ rpm and began using art slicks on a more standard cardboard sleeve. The Audiophile numbers can be found into the hundreds today but the most collectable ones are the early 78 rpm releases, especially the first, AP-1. The 78 rpm speed was mainly to take advantage of the wider audio frequency response that faster speeds like 78 rpm can provide for vinyl microgroove records, hence the label's name (obviously catering to the audiophiles of the 1950s "hi-fi" era, when stereo gear could provide a much wider range of audio than before). Also around 1953, Bell Records released a series of budget-priced plastic 7-inch 78 rpm pop music singles.

In 1968, Reprise planned to release a series of 78 rpm singles from their artists on their label at the time, called the Reprise Speed Series. Only one disc actually saw release, Randy Newman's "I Think It's Going to Rain Today", a track from his self-titled debut album (with "The Beehive State" on the flipside).^[32] Reprise did not proceed further with the series due to a lack of sales for the single, and a lack of general interest in the concept.^[33]

In 1978, guitarist and vocalist Leon Redbone released a promotional 78 rpm record featuring two songs ("Alabama Jubilee" and "Please Don't Talk About Me When I'm Gone") from his Champagne Charlie album.^[34]

In 1980, Stiff Records in the United Kingdom issued a 78 by Joe "King" Carrasco containing the songs "Buena" (Spanish for "good," with the alternate spelling "Bueno" on the label) and "Tuff Enuff". Underground comic cartoonist and 78 rpm record collector Robert Crumb released three vinyl 78s by his Cheap Suit Serenaders in the 1970s.

In the 1990s Rhino Records issued a series of boxed sets of 78 rpm reissues of early rock and roll hits, intended for owners of vintage jukeboxes. The records were made of vinyl, however, and some of the earlier vintage 78 rpm jukeboxes and record players (the ones that were pre-war) were designed with heavy tone arms to play the hard slate-impregnated shellac records of their time. These vinyl Rhino 78's were softer and would be destroyed by old juke boxes and old record players, but play very well on newer 78-capable turntables with modern lightweight tone arms and jewel needles.^[35]

As a special release for Record Store Day 2011, Capitol re-released The Beach Boys single "Good Vibrations" in the form of a 10-inch 78 rpm record (b/w "Heroes and Villains"). More recently, The Reverend Peyton's Big Damn Band has released their tribute to blues guitarist Charley Patton Peyton on Patton on both 12-inch LP and 10-inch 78 rpm.^[36] Both are accompanied with a link to a digital download of the music, acknowledging the probability that purchasers might be unable to play the vinyl recording.

New sizes and materials

Both the microgroove LP  33 ¹⁄₃ rpm record and the 45 rpm single records are made from vinyl plastic that is flexible and unbreakable in normal use, even when they are sent through the mail with care from one place to another. The vinyl records, however, are easier to scratch or gouge, and much more prone to warping compared to most 78 rpm records, which were made of shellac.

In 1931, RCA Victor launched the first commercially available vinyl long-playing record, marketed as program-transcription discs. These revolutionary discs were designed for playback at  33 ¹⁄₃ rpm and pressed on a 30 cm diameter flexible plastic disc, with a duration of about ten minutes playing time per side. 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.^[37] Because of financial hardships that plagued the recording industry during that period (and RCA's own parched revenues), Victor's long-playing records were discontinued by early 1933.

There was also a small batch of longer-playing records issued in the very early 1930s: Columbia introduced 10-inch longer-playing records (18000-D series), as well as a series of double-grooved or longer-playing 10-inch records on their Harmony, Clarion & Velvet Tone "budget" labels. There were also a couple of longer-playing records issued on ARC (for release on their Banner, Perfect, and Oriole labels) and on the Crown label. All of these were phased out in mid-1932.

Vinyl's lower surface noise level than shellac was not forgotten, nor was its durability. In the late 1930s, radio commercials and pre-recorded radio programs being sent to disc jockeys started being pressed in vinyl, so they would not break in the mail. In the mid-1940s, 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-inch (30 cm) 78 rpm records produced by V-Disc for distribution to United States troops in World War II. In the 1940s, 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, Dr. Peter Goldmark and his staff at Columbia Records and at CBS Laboratories undertook efforts to address problems of recording and playing back narrow grooves and developing an inexpensive, reliable consumer playback system. It took about eight years of study, except when it was suspended because of World War II. Finally, the 12-inch (30 cm) Long Play (LP)  33 ¹⁄₃ rpm microgroove record album was introduced by the Columbia Record Company at a New York press conference on June 18, 1948. At the same time, Columbia introduced a vinyl 7 inch  33 ¹⁄₃ rpm microgroove single, calling it ZLP, but it was short-lived and is very rare today, because RCA Victor introduced a 45 rpm single a few months later, which became the standard.

Unwilling to accept and license Columbia's system, in February 1949 RCA Victor, in cooperation with its parent, the Radio Corporation of America, released the first 45 rpm single, 7 inches in diameter with a large center hole. The 45 rpm player included a changing mechanism that allowed multiple disks to be stacked, much as a conventional changer handled 78s. The short playing time of a single 45 rpm side meant that long works, such as symphonies, had to be released on multiple 45s instead of a single LP, but RCA claimed that the new high-speed changer rendered side breaks so brief as to be inaudible or inconsequential. Early 45 rpm records were made from either vinyl or polystyrene.^[38] They had a playing time of eight minutes.^[39]

Another size and format was that of radio transcription discs beginning in the 1940s. These records were usually vinyl, 33 rpm, and 16 inches in diameter. No home record player could accommodate such large records, and they were used mainly by radio stations. They were on average 15 minutes per side and contained several songs or radio program material. These records became less common when tape recorders began being used for radio transcriptions around 1949.

On a few early phonograph systems and radio transcription discs, as well as some entire albums, the direction of the groove is reversed, beginning near the center of the disc and leading to the outside. A small number of records (such as The Monty Python Matching Tie and Handkerchief) were manufactured with multiple separate grooves to differentiate the tracks (usually called "NSC-X2").

Speeds

Shellac era

The earliest rotation speeds varied widely. Most records made in 1900–1925 were recorded at 74–82 revolutions per minute (rpm). Edison Disc Records consistently ran at 80 rpm.

One early attempt at lengthening the playing time should be mentioned. At least one manufacturer in the early 1920s, World Records, produced records that played at a constant linear velocity, controlled by Noel Pemberton Billing's patented add-on governor device.^[40] As these were played from the outside to the inside, the rotational speed of the records increased as reproduction progressed. This action is similar (although in reverse) to that on the modern compact disc and the CLV version of its predecessor, the Philips Laser Disc.

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, such that a 46:1 gear ratio would produce 78.26 rpm. In parts of the world that used 50 Hz current, the standard was 77.92 rpm (3,000 rpm with a 77:2 ratio), which was also the speed at which a strobe disc with 77 lines would "stand still" in 50 Hz light (92 lines for 60 Hz). After World War II these records were retroactively known as 78s, to distinguish them from other newer disc record formats. Earlier they were just called records, or when there was a need to distinguish them from cylinders, disc records.

The older 78 format continued to be mass-produced alongside the newer formats using new materials until about 1960 in the U.S., and in a few countries, such as India (where some Beatles recordings were issued on 78), into the 1960s. For example, Columbia Records' last reissue of Frank Sinatra songs on 78 rpm records was an album called Young at Heart, issued November 1, 1954.^[42] As late as the 1970s, some children's records were released at the 78 rpm speed. In the United Kingdom, the 78 rpm single lasted longer than in the United States and the 45 rpm took longer to become popular. The 78 rpm was overtaken in popularity by the 45 rpm in the late 1950s, as teenagers became increasingly affluent.

Some of Elvis Presley's early singles on Sun Records might have sold more copies on 78 than on 45. This is because the majority of those sales in 1954–55 were to the "hillbilly" market in the South and Southwestern United States, where replacing the family 78 rpm player with a new 45 rpm player was a luxury few could afford at the time. By the end of 1957, RCA Victor announced that 78s accounted for less than 10% of Presley's singles sales, essentially announcing the death throes of the 78 rpm format. The last Presley single released on 78 in the United States was RCA Victor 20-7410, I Got Stung/One Night (1958), while the last 78 in the UK was RCA 1194, A Mess Of Blues/Girl Of My Best Friend (1960).

Microgroove and vinyl era

After World War II, two new competing formats came onto the market and gradually replaced the standard "78": the  33 ¹⁄₃ rpm (often just referred to as the 33 rpm), and the 45 rpm (see above). The  33 ¹⁄₃ rpm LP (for "long-play") format was developed by Columbia Records and marketed in June 1948. The first LP release consisted of 85 12 inch classical pieces starting with the Mendelssohn violin concerto, Nathan Milstein violinist, Philharmonic Symphony of New York conducted by Bruno Walter, Columbia ML-4001. Also released in June 1948 were 3 series of 10 inch "LPs" and a 7-inch "ZLP". RCA Victor developed the 45 rpm format and marketed it in March 1949. The 45s released by RCA in March 1949 were in seven different colors of vinyl depending on the type of music recorded, blues, country, popular etc. Columbia and RCA Victor pursued their own R&D in secret.^[43] Both types of new disc used narrower grooves, intended to be played with smaller stylus—typically 0.001 inches ("1 mil") (25 µm) wide, compared to 0.003 inches (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 pre-amplifiers with multiple selectable equalization curves.

Some recordings, such as books for the blind, were pressed at  16 ²⁄₃ rpm. Prestige Records released jazz records in this format in the late 1950s; for example, two of their Miles Davis albums were paired together in this format. Peter Goldmark, the man who developed the  33 ¹⁄₃ rpm record, developed the Highway Hi-Fi  16 ²⁄₃ rpm record to be played in Chrysler automobiles, but poor performance of the system and weak implementation by Chrysler and Columbia led to the demise of the  16 ²⁄₃ rpm records. Subsequently, the  16 ²⁄₃ rpm speed was used for narrated publications for the blind and visually impaired, and were never widely commercially available, although it was common to see new turntable models with a 16 rpm speed setting produced as late as the 1970s.

Seeburg Corporation introduced the Seeburg Background Music System in 1959, using a  16 ²⁄₃ rpm 9-inch record with 2-inch center hole. Each record held 40 minutes of music per side, recorded at 420 grooves per inch.^[44]

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-inch (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.) In 1949 Capitol and Decca adopted the new LP format and RCA Victor gave in and issued its first LP in January 1950. The 45 rpm size was gaining in popularity, too, and Columbia issued its first 45s in February 1951. By 1954, 200 million 45s had been sold.^[45]

Eventually the 12-inch (300 mm)  33 ¹⁄₃ rpm LP prevailed as the predominant format for musical albums, and 10-inch LPs were no longer issued. The last Columbia Records reissue of any Frank Sinatra songs on a 10-inch LP record was an album called Hall of Fame, CL 2600, issued on October 26, 1956, containing six songs, one each by Tony Bennett, Rosemary Clooney, Johnnie Ray, Frank Sinatra, Doris Day, and Frankie Laine.^[42] The 10-inch LP however had a longer life in the United Kingdom, where important early British rock and roll albums such as Lonnie Donegan's Lonnie Donegan Showcase and Billy Fury's The Sound of Fury were released in that form. The 7-inch (175 mm) 45 rpm disc or "single" established a significant niche for shorter duration discs, typically containing one item on each side. The 45 rpm discs typically emulated the playing time of the former 78 rpm discs, while the 12-inch LP discs eventually provided up to one half-hour of recorded material per side.

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. EP discs were cheaper to produce, and were used in cases where unit sales were likely to be more limited or to reissue LP albums on the smaller format for those people who had only 45 rpm players. LP albums could be purchased 1 EP at a time, with four items per EP, or in a boxed set with 3 EPs or 12 items. The large center hole on 45s allows for easier handling by jukebox mechanisms. EPs were generally discontinued by the late 1950s in the U.S. as three- and four-speed record players replaced the individual 45 players. One indication of the decline of the 45 rpm EP is that the last Columbia Records reissue of Frank Sinatra songs on 45 rpm EP records, called Frank Sinatra (Columbia B-2641) was issued on December 7, 1959.^[42] The EP lasted considerably longer in Europe, and was a popular format during the 1960s for recordings by artists such as Serge Gainsbourg and the Beatles.

In the late 1940s and early 1950s, 45 rpm-only players that lacked speakers and plugged into a jack on the back of a radio were widely available. Eventually, they were replaced by the three–speed record player.

From the mid-1950s through the 1960s, in the U.S. the common home record player or "stereo" (after the introduction of stereo recording) would typically have had these features: a three- or four-speed player (78, 45,  33 ¹⁄₃, and sometimes  16 ²⁄₃ rpm); with changer, a tall spindle that would hold several records and automatically drop a new record on top of the previous one when it had finished playing, a combination cartridge with both 78 and microgroove styli and a way to flip between the two; and some kind of adapter for playing the 45s with their larger center hole. The adapter could be a small solid circle that fit onto the bottom of the spindle (meaning only one 45 could be played at a time) or a larger adaptor that fit over the entire spindle, permitting a stack of 45s to be played.^[41]

RCA Victor 45s were also adapted to the smaller spindle of an LP player with a plastic snap-in insert known as a "spider".^[41] These inserts, commissioned by RCA president David Sarnoff and invented by Thomas Hutchison,^[46] were prevalent starting in the 1960s, selling in the tens of millions per year during the 45 rpm heyday. In countries outside the U.S., 45s often had the smaller album-sized holes, e.g., Australia and New Zealand, or as in the United Kingdom, especially before the 1970s, the disc had a small hole within a circular central section held only by three or four lands so that it could be easily punched out if desired (typically for use in jukeboxes).

Sound enhancements

During the vinyl era, various developments were made or introduced. Stereo finally lost its previous experimental status, and eventually became standard internationally. Quadraphonic sound effectively had to wait for digital formats before finding a permanent position in the market place.

High fidelity

The term "high fidelity" was coined in the 1920s by some manufacturers of radio receivers and phonographs to differentiate their better-sounding products claimed as providing "perfect" sound reproduction.^[47] The term began to be used by some audio engineers and consumers through the 1930s and 1940s. After 1949 a variety of improvements in recording and playback technologies, especially stereo recordings, which became widely available in 1958, gave a boost to the "hi-fi" classification of products, leading to sales of individual components for the home such as amplifiers, loudspeakers, phonographs, and tape players.^[48] High Fidelity and Audio were two magazines that hi-fi consumers and engineers could read for reviews of playback equipment and recordings.

Stereophonic sound

Stereophonic sound recording, which attempts to provide a more natural listening experience by reproducing the spatial locations of sound sources in the horizontal plane, was the natural extension to monophonic recording, and attracted various alternative engineering attempts. The ultimately dominant "45/45" stereophonic record 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 (see Bell Labs Stereo Experiments of 1933) although the system was not exploited commercially until much later.

In this system, each of two stereo channels is carried independently by a separate groove wall, each wall face moving at 45 degrees to the plane of the record surface (hence the system's name) in correspondence with the signal level of that channel. By convention, the inner wall carries the left-hand channel and the outer wall carries the right-hand channel.

While the stylus only moves horizontally when reproducing a monophonic disk recording, on stereo records the stylus moves vertically as well as horizontally. During playback, the movement of a single stylus tracking the groove is sensed independently, e.g., by two coils, each mounted diagonally opposite the relevant groove wall.^[49]

The combined stylus motion can be represented in terms of the vector sum and difference of the two stereo channels. Vertical stylus motion then carries the L-R difference signal and horizontal stylus motion carries the L+R summed signal, the latter representing the monophonic component of the signal in exactly the same manner as a purely monophonic record.

The advantages of the 45/45 system as compared to alternative systems were:

• complete compatibility with monophonic playback systems. A monophonic cartridge reproduces the monophonic component of a stereo record instead of only one of its channels. (However, many monophonic styli had such low vertical compliance that they plowed through the vertical modulation, destroying the stereo information. This led to the common recommendation never to 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;
• equally balanced reproduction, because each channel has equal fidelity (not the case, e.g., with a higher-fidelity laterally recorded channel and a lower-fidelity vertically recorded channel); and,
• higher fidelity in general, because the "difference" signal is usually of low amplitude and is thus less affected by the greater intrinsic distortion of hill-and-dale recording.

In 1957 the first commercial stereo two-channel records were issued first by Audio Fidelity followed by a translucent blue vinyl on Bel Canto Records, the first of which was a multi-colored-vinyl sampler featuring A Stereo Tour of Los Angeles narrated by Jack Wagner on one side, and a collection of tracks from various Bel Canto albums on the back.^[50]

Following in 1958, more stereo LP releases were offered by Audio Fidelity Records in the US and Pye Records in Britain. However, it was not until the mid-to-late 1960s that the sales of stereophonic LPs overtook those of their monophonic equivalents, and became the dominant record type.

Quadraphonic

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 the front-rear difference information on an ultrasonic carrier, which required a special wideband cartridge to capture it on carefully calibrated pickup arm/turntable combinations. CD-4 was even less successful than the two matrixed formats. (A further problem was that no cutting heads were available that could handle the HF information. That was remedied by cutting at half the speed. Later, the special half-speed cutting heads and equalization techniques were employed to get a wider frequency response in stereo with reduced distortion and greater headroom.)

Other enhancements

Under the direction of recording engineer C. Robert Fine, Mercury Records initiated a minimalist single microphone monaural recording technique in 1951. The first record, a Chicago Symphony Orchestra performance of Pictures at an Exhibition, conducted by Rafael Kubelik, 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 35 mm magnetic film instead of half-inch tape for recording. The greater thickness and width of 35 mm 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, Wilma Cozart Fine, using the same method of 3-to-2 mix directly to the master recorder.

Through the 1960s, 1970s, and 1980s, various methods to improve the dynamic range of mass-produced records involved highly advanced disc cutting equipment. These techniques, marketed, to name two, as the CBS DisComputer and Teldec Direct Metal Mastering, were used to reduce inner-groove distortion. RCA Victor introduced another system to reduce 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 compression 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. It also used the earlier advanced method of forward-looking control on groove spacing with respect to volume of sound and position on the disk. Lower recorded volume used closer spacing; higher recorded volume used wider spacing, especially with lower frequencies. Also, the higher track density at lower volumes enabled disk recordings to end farther away from the disk center than usual, helping to reduce endtrack distortion 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 system used mainly on Motown 12-inch singles released between 1978 and 1980. The introduction, drum-breaks, or choruses of a track were indicated by widely separated grooves, giving a visual cue to DJs mixing the records. The appearance of these records is similar to an LP, but they only contain one track each side.

The mid-1970s 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: 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.

Laser turntable

ELPJ, a Japanese-based company, sells a laser turntable that uses a laser to read vinyl discs optically, without physical contact. The laser turntable eliminates record wear and the possibility of accidental scratches, which degrade the sound, but its expense limits use primarily to digital archiving of analog records, and the laser does not play back colored vinyl or picture discs. 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 attracts due to static electric charge is not mechanically pushed out of the groove, worsening sound quality in casual use compared to conventional stylus playback.

In some ways similar to the laser turntable is the IRENE scanning machine for disc records, which images with microphotography in two dimensions, invented by a team of physicists at Lawrence Berkeley Laboratories. IRENE will retrieve the information from a laterally modulated monaural grooved sound source without touching the medium itself, but cannot read vertically modulated information. This excludes grooved recordings such as cylinders and some radio transcriptions that feature a hill-and-dale format of recording, and stereophonic or quadraphonic grooved recordings, which utilize a combination of the two as well as supersonic encoding for quadraphonic.

An offshoot of IRENE, the Confocal Microscope Cylinder Project, can capture a high-resolution 3-D image of the surface, down to 200 µm. In order to convert to a digital sound file, this is then played by a version of the same 'virtual stylus' program developed by the research team in real-time, converted to digital and, if desired, processed through sound-restoration programs.

Formats

Types of records

As recording technology evolved, more specific terms for various types of phonograph records were used in order to describe some aspect of the record: either its correct rotational speed (" 16 ²⁄₃ rpm" (revolutions per minute), " 33 ¹⁄₃ rpm", "45 rpm", "78 rpm") or the material used (particularly "vinyl" to refer to records made of polyvinyl chloride, or the earlier "shellac records" generally the main ingredient in 78s).

Terms such as "long-play" (LP) and "extended-play" (EP) describe multi-track records that play much longer than the single-item-per-side records, which typically do not go much past four minutes per side. An LP can play for up to 30 minutes per side, though most played for about 22 minutes per side, bringing the total playing time of a typical LP recording to about forty-five minutes. Many pre-1952 LPs, however, played for about 15 minutes per side. The 7-inch 45 rpm format normally contains one item per side but a 7-inch EP could achieve recording times of 10 to 15 minutes at the expense of attenuating and compressing the sound to reduce the width required by the groove. EP discs were generally used to make available tracks not on singles including tracks on LPs albums in a smaller, less expensive format for those who had only 45 rpm players. The large center hole on 7-inch 45 rpm records allows for easier handling by jukebox mechanisms. The term "album", originally used to mean a "book" with liner notes, holding several 78 rpm records each in its own "page" or sleeve, no longer has any relation to the physical format: a single LP record, or nowadays more typically a compact disc.

The usual diameters of the holes are 0.286 inches (7.26 mm)^[51] with larger holes on singles in the USA being 1.5 inches (38.1 mm).

Sizes of records in the United States and the UK are generally measured in inches, e.g. 7-inch records, which are generally 45 rpm records. LPs were 10-inch records at first, but soon the 12-inch size became by far the most common. Generally, 78s were 10-inch, but 12-inch and 7-inch and even smaller were made —— the so-called "little wonders".^[52]

Common formats

Diameter	Revolutions per minute	Duration
12 in (30 cm)	33 1⁄3 rpm	45 min Long Play (LP)
	45 rpm	12-inch single, Maxi Single
10 in (25 cm)	33 1⁄3 rpm	Long Play (LP)
	78 rpm	3 minutes
7 in (17.5 cm)	45 rpm	Single
	45 rpm	Single with Extended Play (EP)

Notes:

• Before the mid-1950s the  33 ¹⁄₃ rpm LP was most commonly found in a 10-inch (25 cm) format. The 10-inch format disappeared from United States stores around 1957, but remained common in some markets until the mid-1960s. The 10-inch vinyl format was resurrected in the 1970s for marketing some popular recordings as collectible, and these are occasionally seen today.
• The first disk recordings were invented by Emile Berliner and were pressed as 7 inch approx. 78 rpm recordings between 1887 and 1899. They are rarely found today.
• Columbia pressed many 7 inch  33 ¹⁄₃ rpm vinyl singles in 1949 but were dropped in early 1950 due to the popularity of the RCA 45.^[53]

Less common formats

In March 1949, as RCA released the 45, Columbia released several hundred 7 inch  33 ¹⁄₃ rpm small spindle hole singles. This format was soon dropped as it became clear that the RCA 45 was the single of choice and the Columbia 12 inch LP would be the "album" of choice.^[54] The first release of the 45 came in seven colors: black 47-xxxx popular series, yellow 47-xxxx juvenile series, green (teal) 48-xxxx country series, deep red 49-xxxx classical series, bright red (cerise) 50-xxxx blues/spiritual series, light blue 51-xxxx international series, dark blue 52-xxxx light classics. All colors were soon dropped in favor of black because of production problems. However, yellow and deep red were continued until about 1952.^[55] The first 45 rpm record created for sale was "PeeWee the Piccolo" RCA 47-0147 pressed in yellow translucent vinyl at the Sherman Avenue plant, Indianapolis on December 7, 1948, by R. O. Price, plant manager.^[56]

In the 1970s, the government of Bhutan produced now-collectible postage stamps on playable vinyl mini-discs.^[57]

Structure

The normal commercial disc is engraved with two sound-bearing concentric spiral grooves, one on each side, running from the outside edge towards the center. The last part of the spiral meets an earlier part to form a circle. The sound is encoded by fine variations in the edges of the groove that cause a stylus (needle) placed in it to vibrate at acoustic frequencies when the disc is rotated at the correct speed. Generally, the outer and inner parts of the groove bear no intended sound (an exception is Split Enz's Mental Notes).

Increasingly from the early 20th century,^[58] and almost exclusively since the 1920s, both sides of the record have been used to carry the grooves. Occasional records have been issued since then with a recording on only one side. In the 1980s Columbia records briefly issued a series of less expensive one-sided 45 rpm singles.

The majority of non-78 rpm records are pressed on black vinyl. The coloring material used to blacken the transparent PVC plastic mix is carbon black, which increases the strength of the disc and makes it opaque. Polystyrene is often used for 7-inch records.

Some records are pressed on colored vinyl or with paper pictures embedded in them ("picture discs"). Certain 45 rpm RCA or RCA Victor Red Seal records used red translucent vinyl for extra "Red Seal" effect. During the 1980s there was a trend for releasing singles on colored vinyl—sometimes with large inserts that could be used as posters. This trend has been revived recently with 7-inch singles.

Since its inception in 1948, vinyl record standards for the United States follow the guidelines of the Recording Industry Association of America (RIAA).^[59] The inch dimensions are nominal, not precise diameters. The actual dimension of a 12-inch record is 302 mm (11.89 in), for a 10-inch it is 250 mm (9.84 in), and for a 7-inch it is 175 mm (6.89 in).

Records made in other countries are standardized by different organizations, but are very similar in size. The record diameters are typically nominally 300 mm, 250 mm and 175 mm.

There is an area about 3 mm (0.12 in) wide at the outer edge of the disk, called the lead-in or run-in, where the groove is widely spaced and silent. The stylus is lowered onto the lead-in, without damaging the recorded section of the groove.

Between tracks on the recorded section of an LP record there is usually a short gap of around 1 mm (0.04 in) where the groove is widely spaced. This space is clearly visible, making it easy to find a particular track.

Towards the center, at the end of the groove, there is another wide-pitched section known as the lead-out. At the very end of this section the groove joins itself to form a complete circle, called the lock groove; when the stylus reaches this point, it circles repeatedly until lifted from the record. On some recordings (for example Sgt. Pepper's Lonely Hearts Club Band by The Beatles, Super Trouper by ABBA and Atom Heart Mother by Pink Floyd), the sound continues on the lock groove, which gives a strange repeating effect. Automatic turntables rely on the position or angular velocity of the arm, as it reaches the wider spacing in the groove, to trigger a mechanism that lifts the arm off the record. Precisely because of this mechanism, most automatic turntables are incapable of playing any audio in the lock groove, since they will lift the arm before it reaches that groove.

The catalog number and stamper ID is written or stamped in the space between the groove in the lead-out on the master disc, resulting in visible recessed writing on the final version of a record. Sometimes the cutting engineer might add handwritten comments or their signature, if they are particularly pleased with the quality of the cut. These are generally referred to as "run-out etchings".

When auto-changing turntables were commonplace, records were typically pressed with a raised (or ridged) outer edge and a raised label area, allowing records to be stacked onto each other without the delicate grooves coming into contact, reducing the risk of damage. Auto-changers included a mechanism to support a stack of several records above the turntable itself, dropping them one at a time onto the active turntable to be played in order. Many longer sound recordings, such as complete operas, were interleaved across several 10-inch or 12-inch discs for use with auto-changing mechanisms, so that the first disk of a three-disk recording would carry sides 1 and 6 of the program, while the second disk would carry sides 2 and 5, and the third, sides 3 and 4, allowing sides 1, 2, and 3 to be played automatically; then the whole stack reversed to play sides 4, 5, and 6.

Vinyl quality

The sound quality and durability of vinyl records is highly dependent on the quality of the vinyl. During the early 1970s, as a cost-cutting move, much of the industry began reducing the thickness and quality of vinyl used in mass-market manufacturing. The technique was marketed by RCA Victor as the Dynaflex (125 g) process, but was considered inferior by most record collectors.^[60] Most vinyl records are pressed from a mix of 70% virgin and 30% recycled vinyl.

New or "virgin" heavy/heavyweight (180–220 g) vinyl is commonly used for modern audiophile vinyl releases in all genres. Many collectors prefer to have heavyweight vinyl albums, which have been reported to have better sound than normal vinyl because of their higher tolerance against deformation caused by normal play.^[61] 180 g vinyl is more expensive to produce only because it uses more vinyl. Manufacturing processes are identical regardless of weight. In fact, pressing lightweight records requires more care. An exception is the propensity of 200 g pressings to be slightly more prone to non-fill, when the vinyl biscuit does not sufficiently fill a deep groove during pressing (percussion or vocal amplitude changes are the usual locations of these artifacts). This flaw causes a grinding or scratching sound at the non-fill point.

Since most vinyl records contain up to 30% recycled vinyl, impurities can accumulate in the record and cause even a brand-new record to have audio artifacts such as clicks and pops. Virgin vinyl means that the album is not from recycled plastic, and will theoretically be devoid of these impurities. In practice, this depends on the manufacturer's quality control.

The "orange peel" effect on vinyl records is caused by worn molds. Rather than having the proper mirror-like finish, the surface of the record will have a texture that looks like orange peel. This introduces noise into the record, particularly in the lower frequency range. With direct metal mastering (DMM), the master disc is cut on a copper-coated disc, which can also have a minor "orange peel" effect on the disc itself. As this "orange peel" originates in the master rather than being introduced in the pressing stage, there is no ill effect as there is no physical distortion of the groove.

Original master discs are created by lathe-cutting: a lathe is used to cut a modulated groove into a blank record. The blank records for cutting used to be cooked up, as needed, by the cutting engineer, using what Robert K. Morrison describes as a "metallic soap", containing lead litharge, ozokerite, barium sulfate, montan wax, stearin and paraffin, among other ingredients. Cut "wax" sound discs would be placed in a vacuum chamber and gold-sputtered to make them electrically conductive for use as mandrels in an electroforming bath, where pressing stamper parts were made. Later, the French company Pyral invented a ready-made blank disc having a thin nitro-cellulose lacquer coating (approximately 7 mils thickness on both sides) that was applied to an aluminum substrate. Lacquer cuts result in an immediately playable, or processable, master record. If vinyl pressings are wanted, the still-unplayed sound disc is used as a mandrel for electroforming nickel records that are used for manufacturing pressing stampers. The electroformed nickel records are mechanically separated from their respective mandrels. This is done with relative ease because no actual "plating" of the mandrel occurs in the type of electrodeposition known as electroforming, unlike with electroplating, in which the adhesion of the new phase of metal is chemical and relatively permanent. The one-molecule-thick coating of silver (that was sprayed onto the processed lacquer sound disc in order to make its surface electrically conductive) reverse-plates onto the nickel record's face. This negative impression disc (having ridges in place of grooves) is known as a nickel master, "matrix" or "father". The "father" is then used as a mandrel to electroform a positive disc known as a "mother". Many mothers can be grown on a single "father" before ridges deteriorate beyond effective use. The "mothers" are then used as mandrels for electroforming more negative discs known as "sons". Each "mother" can be used to make many "sons" before deteriorating. The "sons" are then converted into "stampers" by center-punching a spindle hole (which was lost from the lacquer sound disc during initial electroforming of the "father"), and by custom-forming the target pressing profile. This allows them to be placed in the dies of the target (make and model) record press and, by center-roughing, to facilitate the adhesion of the label, which gets stuck onto the vinyl pressing without any glue. In this way, several million vinyl discs can be produced from a single lacquer sound disc. When only a few hundred discs are required, instead of electroforming a "son" (for each side), the "father" is removed of its silver and converted into a stamper. Production by this latter method, known as the "two-step-process" (as it does not entail creation of "sons" but does involve creation of "mothers", which are used for test playing and kept as "safeties" for electroforming future "sons") is limited to a few hundred vinyl pressings. The pressing count can increase if the stamper holds out and the quality of the vinyl is high. The "sons" made during a "three-step" electroforming make better stampers since they don't require silver removal (which reduces some high fidelity because of etching erasing part of the smallest groove modulations) and also because they have a stronger metal structure than "fathers".

Limitations

Shellac

Shellac 78s are brittle, and must be handled carefully. In the event of a 78 breaking, the pieces might remain loosely connected by the label and still be playable if the label holds them together, although there is a loud "pop" with each pass over the crack, and breaking of the stylus is likely.

Breakage was very common in the shellac era. In the 1934 John O'Hara novel, Appointment in Samarra, the protagonist "broke one of his most favorites, Whiteman's Lady of the Evening ... He wanted to cry but could not." A poignant moment in J. D. Salinger's 1951 novel The Catcher in the Rye occurs after the adolescent protagonist buys a record for his younger sister but drops it and "it broke into pieces ... I damn-near cried, it made me feel so terrible." A sequence where a school teacher's collection of 78 rpm jazz records is smashed by a group of rebellious students is a key moment in the film Blackboard Jungle.

Another problem with shellac was that the size of the disks tended to be larger because it was limited to 80–100 groove walls per inch before the risk of groove collapse became too high, whereas vinyl could have up to 260 groove walls per inch.^[62][63]

By the time World War II began, major labels were experimenting with laminated records. As stated above, and in several record advertisements of the period, the materials that make for a quiet surface (shellacque) are notoriously weak and brittle. Conversely the materials that make for a strong disc (cardboard and other fiber products) are not those known for allowing a quiet noise-free surface.

Vinyl

Vinyl records do not break easily, but the soft material is easily scratched. Vinyl readily acquires a static charge, attracting dust that is difficult to remove completely. Dust and scratches cause audio clicks and pops. In extreme cases, they can cause the needle to skip over a series of grooves, or worse yet, cause the needle to skip backwards, creating a "locked groove" that repeats over and over. This is the origin of the phrase "like a broken record" or "like a scratched record", which is often used to describe a person or thing that continually repeats itself.^[64] Locked grooves are not uncommon and were even heard occasionally in radio broadcasts.

Vinyl records can be warped by heat, improper storage, exposure to sunlight, or manufacturing defects such as excessively tight plastic shrinkwrap on the album cover. A small degree of warp was common, and allowing for it was part of the art of turntable and tonearm design. "wow" (once-per-revolution pitch variation) could result from warp, or from a spindle hole that was not precisely centered. Standard practice for LPs was to place the LP in a paper or plastic inner cover. This, if placed within the outer cardboard cover so that the opening was entirely within the outer cover, was said to reduce ingress of dust onto the record surface. Singles, with rare exceptions, had simple paper covers with no inner cover.

A further limitation of the gramophone record is that fidelity steadily declines as playback progresses; there is more vinyl per second available for fine reproduction of high frequencies at the large-diameter beginning of the groove than exist at the smaller-diameters close to the end of the side. At the start of a groove on an LP there are 510 mm of vinyl per second traveling past the stylus while the ending of the groove gives 200–210 mm of vinyl per second — less than half the linear resolution.^[65] Distortion towards the end of the side is likely to become more apparent as record wear increases.

Another problem arises because of the geometry of the tonearm. Master recordings are cut on a recording lathe where a sapphire stylus moves radially across the blank, suspended on a straight track and driven by a lead screw. Most turntables use a pivoting tonearm, introducing side forces and pitch and azimuth errors, and thus distortion in the playback signal. Various mechanisms were devised in attempts to compensate, with varying degrees of success. See more at phonograph.

There is controversy about the relative quality of CD sound and LP sound when the latter is heard under the very best conditions (see Analog vs. Digital sound argument). It is notable, however, that one technical advantage with vinyl compared to the optical CD is that if correctly handled and stored, the vinyl record will be playable for centuries, which is somewhat longer than the optical CD.

Frequency response and noise

In 1925, electric recording extended the recorded frequency range from acoustic recording (168–2,000 Hz) by 2.5 octaves to 100–5,000 Hz. Even so, these early electronically recorded records used the exponential-horn phonograph (see Orthophonic Victrola) for reproduction.

CD-4 LPs contain two sub-carriers, one in the left groove wall and one in the right groove wall. These sub-carriers use special FM-PM-SSBFM (Frequency Modulation-Phase Modulation-Single Sideband Frequency Modulation) and have signal frequencies that extend to 45 kHz. CD-4 sub-carriers could be played with any type stylus as long as the pickup cartridge had CD-4 frequency response. The recommended stylus for CD-4 as well as regular stereo records was a line contact or Shibata type.

Gramophone sound includes rumble, which is low-frequency (below about 30 Hz) mechanical noise generated by the motor bearings and picked up by the stylus. Equipment of modest quality is relatively unaffected by these issues, as the amplifier and speaker will not reproduce such low frequencies, but high-fidelity turntable assemblies need careful design to minimize audible rumble.

Room vibrations will also be picked up if the connections from pedestal to turntable and from turntable to pickup arm are not well isolated.

Tonearm skating forces and other perturbations are also picked up by the stylus. This is a form of frequency multiplexing as the control signal (restoring force) used to keep the stylus in the groove is carried by the same mechanism as the sound itself. Subsonic frequencies below about 20 Hz in the audio signal are dominated by tracking effects, which is one form of unwanted rumble ("tracking noise") and merges with audible frequencies in the deep bass range up to about 100 Hz. High fidelity sound equipment can reproduce tracking noise and rumble. During a quiet passage, woofer speaker cones can sometimes be seen to vibrate with the subsonic tracking of the stylus, at frequencies as low as just above 0.5 Hz (the frequency at which a  33 ¹⁄₃ rpm record turns on the turntable;  ⁵⁄₉ Hz exactly on an ideal turntable). Another reason for very low frequency material can be a warped disk: its undulations produce frequencies of only a few hertz and present day amplifiers have large power bandwidths. For this reason, many stereo receivers contained a switchable subsonic filter. Some subsonic content is directly out of phase in each channel. If played back on a mono subwoofer system, the noise will cancel, significantly reducing the amount of rumble that is reproduced.

High frequency hiss is generated as the stylus rubs against the vinyl, and dirt and dust on the vinyl produces popping and ticking sounds. The latter can be reduced somewhat by cleaning the record prior to playback.

Equalization

Due to recording mastering and manufacturing limitations, both high and low frequencies were removed from the first recorded signals by various formulae. With low frequencies, the stylus must swing a long way from side to side, requiring the groove to be wide, taking up more space and limiting the playing time of the record. At high frequencies, hiss, pops, and ticks are significant. These problems can be reduced by using equalization to an agreed standard. During recording the amplitude of low frequencies is reduced, thus reducing the groove width required, and the amplitude at high frequencies is increased. The playback equipment boosts bass and cuts treble so as to restore the tonal balance in the original signal; this also reduces the high frequency noise. Thus more music will fit on the record, and noise is reduced.

The current standard is called RIAA equalization. It was agreed upon in 1952 and implemented in the United States in 1955; it was not widely used in other countries until the 1970s. Prior to that, especially from 1940, some 100 different formulae were used by the record manufacturers.

History of equalization

In 1926 Joseph P. Maxwell and Henry C. Harrison from Bell Telephone Laboratories disclosed that the recording pattern of the Western Electric "rubber line" magnetic disc cutter had a constant velocity characteristic. This meant that as frequency increased in the treble, recording amplitude decreased. Conversely, in the bass as frequency decreased, recording amplitude increased. Therefore, it was necessary to attenuate the bass frequencies below about 250 Hz, the bass turnover point, in the amplified microphone signal fed to the recording head. Otherwise, bass modulation became excessive and overcutting took place into the next record groove. When played back electrically with a magnetic pickup having a smooth response in the bass region, a complementary boost in amplitude at the bass turnover point was necessary. G. H. Miller in 1934 reported that when complementary boost at the turnover point was used in radio broadcasts of records, the reproduction was more realistic and many of the musical instruments stood out in their true form.

West in 1930 and later P. G. A. H. Voigt (1940) showed that the early Wente-style condenser microphones contributed to a 4 to 6 dB midrange brilliance or pre-emphasis in the recording chain. This meant that the electrical recording characteristics of Western Electric licensees such as Columbia Records and Victor Talking Machine Company in the 1925 era had a higher amplitude in the midrange region. Brilliance such as this compensated for dullness in many early magnetic pickups having drooping midrange and treble response. As a result, this practice was the empirical beginning of using pre-emphasis above 1,000 Hz in 78 rpm and  33 ¹⁄₃ rpm records.

Over the years a variety of record equalization practices emerged and there was no industry standard. For example, in Europe recordings for years required playback with a bass turnover setting of 250–300 Hz and a treble roll-off at 10,000 Hz ranging from 0 to −5 dB or more. In the US there were more varied practices and a tendency to use higher bass turnover frequencies such as 500 Hz as well as a greater treble rolloff like −8.5 dB and even more to record generally higher modulation levels on the record.

Evidence from the early technical literature concerning electrical recording suggests that it wasn't until the 1942–1949 period that there were serious efforts to standardize recording characteristics within an industry. Heretofore, electrical recording technology from company to company was considered a proprietary art all the way back to the 1925 Western Electric licensed method used by Columbia and Victor. For example, what Brunswick-Balke-Collender (Brunswick Corporation) did was different from the practices of Victor.

Broadcasters were faced with having to adapt daily to the varied recording characteristics of many sources: various makers of "home recordings" readily available to the public, European recordings, lateral-cut transcriptions, and vertical-cut transcriptions. Efforts were started in 1942 to standardize within the National Association of Broadcasters (NAB), later known as the National Association of Radio and Television Broadcasters (NARTB). The NAB, among other items, issued recording standards in 1949 for laterally and vertically cut records, principally transcriptions. A number of 78 rpm record producers as well as early LP makers also cut their records to the NAB/NARTB lateral standard.

The lateral cut NAB curve was remarkably similar to the NBC Orthacoustic curve that evolved from practices within the National Broadcasting Company since the mid-1930s. Empirically, and not by any formula, it was learned that the bass end of the audio spectrum below 100 Hz could be boosted somewhat to override system hum and turntable rumble noises. Likewise at the treble end beginning at 1,000 Hz, if audio frequencies were boosted by 16 dB at 10,000 Hz the delicate sibilant sounds of speech and high overtones of musical instruments could survive the noise level of cellulose acetate, lacquer/aluminum, and vinyl disc media. When the record was played back using a complementary inverse curve, signal-to-noise ratio was improved and the programming sounded more lifelike.

When the Columbia LP was released in June 1948, the developers subsequently published technical information about the  33 ¹⁄₃ rpm microgroove long playing record. Columbia disclosed a recording characteristic showing that it was like the NAB curve in the treble, but had more bass boost or pre-emphasis below 200 Hz. The authors disclosed electrical network characteristics for the Columbia LP curve. This was the first such curve based on formulae.

In 1951, at the beginning of the post-World War II high fidelity (hi-fi) popularity, the Audio Engineering Society (AES) developed a standard playback curve. This was intended for use by hi-fi amplifier manufacturers. If records were engineered to sound good on hi-fi amplifiers using the AES curve, this would be a worthy goal towards standardization. This curve was defined by the time constants of audio filters and had a bass turnover of 400 Hz and a 10,000 Hz rolloff of −12 dB.

RCA Victor and Columbia were in a market war concerning which recorded format was going to win: the Columbia LP versus the RCA Victor 45 rpm disc (released in February 1949). Besides also being a battle of disc size and record speed, there was a technical difference in the recording characteristics. RCA Victor was using "new orthophonic," whereas Columbia was using the LP curve.

Ultimately, the New Orthophonic curve was disclosed in a publication by R.C. Moyer of RCA Victor in 1953. He traced RCA Victor characteristics back to the Western Electric "rubber line" recorder in 1925 up to the early 1950s laying claim to long-held recording practices and reasons for major changes in the intervening years. The RCA Victor New Orthophonic curve was within the tolerances for the NAB/NARTB, Columbia LP, and AES curves. It eventually became the technical predecessor to the RIAA curve.

As the RIAA curve was essentially an American standard, it had little impact outside the USA until the late 1970s when European recording labels began to adopt the RIAA equalization. It was even later when some Asian recording labels adopted the RIAA standard. In 1989, many Eastern European recording labels and Russian recording labels such as Melodiya were still using their own CCIR equalization. Hence the RIAA curve did not truly become a global standard until the late 1980s.

Further, even after officially agreeing to implement the RIAA equalization curve, many recording labels continued to use their own proprietary equalization even well into the 1970s. Columbia is one such prominent example in the USA, as are Decca, Teldec and Deutsche Grammophon in Europe.^[66]

Sound fidelity

Overall sound fidelity of records produced acoustically using horns instead of microphones had a distant, hollow tone quality. Some voices and instruments recorded better than others; Enrico Caruso, a famous tenor, was one popular recording artist of the acoustic era whose voice was well matched to the recording horn. It has been asked, "Did Caruso make the phonograph, or did the phonograph make Caruso?"

Delicate sounds and fine overtones were mostly lost, because it took a lot of sound energy to vibrate the recording horn diaphragm and cutting mechanism. There were acoustic limitations due to mechanical resonances in both the recording and playback system. Some pictures of acoustic recording sessions show horns wrapped with tape to help mute these resonances. Even an acoustic recording played back electrically on modern equipment sounds like it was recorded through a horn, notwithstanding a reduction in distortion because of the modern playback. Toward the end of the acoustic era, there were many fine examples of recordings made with horns.

Electric recording which developed during the time that early radio was becoming popular (1925) benefited from the microphones and amplifiers used in radio studios. The early electric recordings were reminiscent tonally of acoustic recordings, except there was more recorded bass and treble as well as delicate sounds and overtones cut on the records. This was in spite of some carbon microphones used, which had resonances that colored the recorded tone. The double button carbon microphone with stretched diaphragm was a marked improvement. Alternatively, the Wente style condenser microphone used with the Western Electric licensed recording method had a brilliant midrange and was prone to overloading from sibilants in speech, but generally it gave more accurate reproduction than carbon microphones.

It was not unusual for electric recordings to be played back on acoustic phonographs. The Victor Orthophonic phonograph was a prime example where such playback was expected. In the Orthophonic, which benefited from telephone research, the mechanical pickup head was redesigned with lower resonance than the traditional mica type. Also, a folded horn with an exponential taper was constructed inside the cabinet to provide better impedance matching to the air. As a result, playback of an Orthophonic record sounded like it was coming from a radio.

Eventually, when it was more common for electric recordings to be played back electrically in the 1930s and 1940s, the overall tone was much like listening to a radio of the era. Magnetic pickups became more common and were better designed as time went on, making it possible to improve the damping of spurious resonances. Crystal pickups were also introduced as lower cost alternatives. The dynamic or moving coil microphone was introduced around 1930 and the velocity or ribbon microphone in 1932. Both of these high quality microphones became widespread in motion picture, radio, recording, and public address applications.

Over time, fidelity, dynamic and noise levels improved to the point that it was harder to tell the difference between a live performance in the studio and the recorded version. This was especially true after the invention of the variable reluctance magnetic pickup cartridge by General Electric in the 1940s when high quality cuts were played on well-designed audio systems. The Capehart radio/phonographs of the era with large diameter electrodynamic loudspeakers, though not ideal, demonstrated this quite well with "home recordings" readily available in the music stores for the public to buy.

There were important quality advances in recordings specifically made for radio broadcast. In the early 1930s Bell Telephone Laboratories and Western Electric announced the total reinvention of disc recording: the Western Electric Wide Range System, "The New Voice of Action". The intent of the new Western Electric system was to improve the overall quality of disc recording and playback. The recording speed was  33 ¹⁄₃ rpm, originally used in the Western Electric/ERPI movie audio disc system implemented in the early Warner Brothers' Vitaphone "talkies" of 1927.

The newly invented Western Electric moving coil or dynamic microphone was part of the Wide Range System. It had a flatter audio response than the old style Wente condenser type and didn't require electronics installed in the microphone housing. Signals fed to the cutting head were pre-emphasized in the treble region to help override noise in playback. Groove cuts in the vertical plane were employed rather than the usual lateral cuts. The chief advantage claimed was more grooves per inch that could be crowded together, resulting in longer playback time. Additionally, the problem of inner groove distortion, which plagued lateral cuts, could be avoided with the vertical cut system. Wax masters were made by flowing heated wax over a hot metal disc thus avoiding the microscopic irregularities of cast blocks of wax and the necessity of planing and polishing.

Vinyl pressings were made with stampers from master cuts that were electroplated in vacuo by means of gold sputtering. Audio response was claimed out to 8,000 Hz, later 13,000 Hz, using light weight pickups employing jeweled styli. Amplifiers and cutters both using negative feedback were employed thereby improving the range of frequencies cut and lowering distortion levels. Radio transcription producers such as World Broadcasting System and Associated Music Publishers (AMP) were the dominant licensees of the Western Electric wide range system and towards the end of the 1930s were responsible for two-thirds of the total radio transcription business. These recordings use a bass turnover of 300 Hz and a 10,000 Hz rolloff of −8.5 dB.

Developmentally, much of the technology of the long playing record, successfully released by Columbia in 1948, came from wide range radio transcription practices. The use of vinyl pressings, increased length of programming, and general improvement in audio quality over 78 rpm records were the major selling points.

The complete technical disclosure of the Columbia LP by Peter C. Goldmark, Rene' Snepvangers and William S. Bachman in 1949 made it possible for a great variety of record companies to get into the business of making long playing records. The business grew quickly and interest spread in high fidelity sound and the do-it-yourself market for pickups, turntables, amplifier kits, loudspeaker enclosure plans, and AM/FM radio tuners. The LP record for longer works, 45 rpm for pop music, and FM radio became high fidelity program sources in demand. Radio listeners heard recordings broadcast and this in turn generated more record sales. The industry flourished.

Evolutionary steps

Technology used in making recordings also developed and prospered. There were ten major evolutionary steps that improved LP production and quality during a period of approximately forty years.

1. Electrical transcriptions and 78s were first used as sources to master LP lacquer/aluminium cuts in 1948. This was before magnetic tape was commonly employed for mastering. Variable pitch groove spacing helped enable greater recorded dynamic levels. The heated stylus improved the cutting of high frequencies. Gold sputtering in vacuo became increasingly used to make high quality matrices from the cuts to stamp vinyl records.
2. Decca in Britain utilised high-quality wide range condenser microphones for the Full Frequency Range Recording (FFRR) system c. 1949. Wax mastering was employed to produce Decca/London LPs. This created considerable interest in the United States, and served to raise the customer's overall expectations of quality in microgroove records.
3. Tape recording with condenser microphones became a long used standard operating procedure in mastering lacquer/aluminium cuts. This improved the overall pickup of high quality sound and enabled tape editing. Over the years there were variations in the kinds of tape recorders used, such as the width and number of tracks employed, including 35 mm magnetic film technology.
4. Production of stereo tape masters and the stereo LP in 1958 brought significant improvements in recording technology.
5. Limitations in the disc cutting part of the process later generated the idea that half-speed mastering would improve quality (in which the source tape is played at half-speed and the lacquer/aluminium disc cut at  16 ²⁄₃ rpm rather than  33 ¹⁄₃ rpm).
6. Some 12 inch LPs were cut at 45 rpm claiming better quality sound, but this practice was short-lived.
7. Efforts were made in the 1970s to record as many as four audio channels on an LP (quadraphonic) by means of matrix and modulated carrier methods. This development was neither a widespread success nor long lasting.
8. Efforts were also made to simplify the chain of equipment in the recording process and return to live recording directly to the disc master.
9. Noise reduction systems were also used in tape mastering of some LPs, as well as in the LP itself.
10. As video recorder technology improved it became possible to modify them and use analogue to digital converters (codecs) for digital sound recording. This brought greater dynamic range to tape mastering, combined with low noise and distortion, and freedom from drop outs as well as pre- and post-echo. The digital recording was played back providing a high quality analogue signal to master the lacquer/aluminium cut.

Shortcomings

At the time of the introduction of the compact disc (CD) in 1982, the stereo LP pressed in vinyl was at the high point of its development. Still, it continued to suffer from a variety of limitations:

• The stereo image was not made up of fully discrete Left and Right channels; each channel's signal coming out of the cartridge contained a small amount of the signal from the other channel, with more crosstalk at higher frequencies. High-quality disc cutting equipment was capable of making a master disc with 30–40 dB of stereo separation at 1000 Hz, but the playback cartridges had lesser performance of about 20 to 30 dB of separation at 1000 Hz, with separation decreasing as frequency increased, such that at 12 kHz the separation was about 10–15 dB.^[67] A common modern view is that stereo isolation must be higher than this to achieve a proper stereo soundstage. However, in the 1950s the BBC determined in a series of tests that only 20–25 dB is required for the impression of full stereo separation.^[68]

	LP pre echo The empty space before the start of the music has been amplified +15dB to reveal the pre-echo.
Problems playing this file? See media help.

• Thin, closely spaced spiral grooves that allow for increased playing time on a  33 ¹⁄₃ rpm microgroove LP lead to a tinny pre-echo warning of upcoming loud sounds. The cutting stylus unavoidably transfers some of the subsequent groove wall's impulse signal into the previous groove wall. It is discernible by some listeners throughout certain recordings, but a quiet passage followed by a loud sound will allow anyone to hear a faint pre-echo of the loud sound occurring 1.8 seconds ahead of time.^[69] This problem can also appear as "post"-echo, with a tinny ghost of the sound arriving 1.8 seconds after its main impulse.
• Factory problems involving incomplete flow of hot vinyl within the stamper can fail to accurately recreate a small section of one side of the groove, a problem called non-fill. It usually appears on the first item on a side if present at all. Non-fill makes itself known as a tearing, grating or ripping sound.
• A static electric charge can build up on the surface of the spinning record and discharge into the stylus, making a loud "pop". In very dry climates, this can happen several times per minute. Subsequent plays of the same record do not have pops in the same places in the music as the static buildup isn't tied to variations in the groove.
• An off-center stamping will apply a slow 0.56 Hz modulation to the playback, affecting pitch due to the modulating speed that the groove runs under the stylus. The effect becomes gradually more acute during playback as the stylus moves closer to the center of the record. It also affects tonality because the stylus is pressed alternately against one groove wall and then the other, making the frequency response change in each channel. This problem is often called "wow", though turntable and motor problems can also cause pitch-only "wow".
• Tracking force of the stylus is not always the same from beginning to end of the groove. Stereo balance can shift as the recording progresses.
• Outside electrical interference may be amplified by the magnetic cartridge. Common household wallplate SCR dimmers sharing AC lines may put noise into the playback, as can poorly shielded electronics and strong radio transmitters.
• Loud sounds in the environment may be transmitted mechanically from the turntable's sympathetic vibration into the stylus. Heavy footfalls can bounce the needle out of the groove.
• Because of a slight slope in the lead-in groove, it is possible for the stylus to skip ahead several grooves when settling into position at the start of the recording.
• The LP is delicate. Any accidental fumbling with the stylus or dropping of the record onto a sharp corner can scratch the record permanently, creating a series of "ticks" and "pops" heard at each subsequent playback. Heavier accidents can cause the stylus to break through the groove wall as it plays, creating a permanent skip that will cause the stylus to either skip ahead to the next groove or skip back to the previous groove. A skip going to the previous groove is called a broken record; the same section of 1.8 seconds of LP (1.3 if 45 rpm) music will repeat over and over until the stylus is lifted off the record. It is also possible to put a slight pressure on the headshell causing the stylus to stay in the desired groove, without having a playback break. This requires some skill, but is of great use when, for instance, digitizing a recording, as no information is skipped.

LP versus CD

Audiophiles have differed over the relative merits of the LP versus the CD since the digital disc was introduced. Vinyl records are still prized for their reproduction of analog recordings. The LP's drawbacks, however, include surface noise, tracking error, pitch variations and greater sensitivity to handling. Modern anti-aliasing filters and oversampling systems used in digital recordings have reduced problems observed with early CD players.

There is a theory that vinyl records can audibly represent higher frequencies than compact discs. According to Red Book specifications, the compact disc has a frequency response of 20 Hz up to 22,050 Hz, and most CD players measure flat within a fraction of a decibel from at least 20 Hz to 20 kHz at full output. Turntable rumble obscures the low-end limit of vinyl but the upper end can be, with some cartridges, reasonably flat within a few decibels to 30 kHz, with gentle roll-off. Carrier signals of Quad LPs popular in the 1970s were at 30 kHz to be out of the range of human hearing. The average human auditory system is sensitive to frequencies from 20 Hz to a maximum of around 20,000 Hz.^[70] The upper and lower frequency limits of human hearing vary per person.

Production

For the first several decades of disc record manufacturing, sound was recorded directly on to the "master disc" at the recording studio. From about 1950 on (earlier for some large record companies, later for some small ones) it became usual to have the performance first recorded on audio tape, which could then be processed and/or edited, and then dubbed on to the master disc. A record cutter would engrave the grooves into the master disc. Early versions of these master discs were soft wax, and later a harder lacquer was used. The mastering process was originally something of an art as the operator had to manually allow for the changes in sound which affected how wide the space for the groove needed to be on each rotation.

Preservation

As the playing of gramophone records causes gradual degradation of the recording, they are best preserved by transferring them onto other media and playing the records as rarely as possible. They need to be stored on edge, and do best under environmental conditions that most humans would find comfortable. The medium needs to be kept clean, but alcohol should only be used on PVC or optical media, not on 78s.^[71] The equipment for playback of certain formats (e.g., 16 and 78 rpm) is manufactured only in small quantities, leading to increased difficulty in finding equipment to play the recordings.

Where old disc recordings are considered to be of artistic or historic interest, from before the era of tape or where no tape master exists, archivists play back the disc on suitable equipment and record the result, typically onto a digital format, which can be copied and manipulated to remove analog flaws without any further damage to the source recording. For example, Nimbus Records uses a specially built horn record player^[72] to transfer 78s. Anyone can do this using a standard record player with a suitable pickup, a phono-preamp (pre-amplifier) and a typical personal computer. However, for accurate transfer, professional archivists carefully choose the correct stylus shape and diameter, tracking weight, equalisation curve and other playback parameters and use high-quality analogue-to-digital converters.^[73]

As an alternative to playback with a stylus, a recording can be read optically, processed with software that calculates the velocity that the stylus would be moving in the mapped grooves and converted to a digital recording format. This does no further damage to the disc and generally produces a better sound than normal playback. This technique also has the potential to allow for reconstruction of broken or otherwise damaged discs.^[74]

Current status

Groove recordings, first designed in the final quarter of the 19th century, held a predominant position for nearly a century—withstanding competition from reel-to-reel tape, the 8-track cartridge, and the compact cassette. In 1988, the compact disc surpassed the gramophone record in unit sales. Vinyl records experienced a sudden decline in popularity between 1988 and 1991,^[75] when the major label distributors restricted their return policies, which retailers had been relying on to maintain and swap out stocks of relatively unpopular titles. First the distributors began charging retailers more for new product if they returned unsold vinyl, and then they stopped providing any credit at all for returns. Retailers, fearing they would be stuck with anything they ordered, only ordered proven, popular titles that they knew would sell, and devoted more shelf space to CDs and cassettes. Record companies also deleted many vinyl titles from production and distribution, further undermining the availability of the format and leading to the closure of pressing plants. This rapid decline in the availability of records accelerated the format's decline in popularity, and is seen by some as a deliberate ploy to make consumers switch to CDs, which were more profitable for the record companies.^{[76][77][78][79]}

In spite of their flaws, such as the lack of portability, records still have enthusiastic supporters. Vinyl records continue to be manufactured and sold today,^[80] especially by independent rock bands and labels, although record sales are considered to be a niche market composed of audiophiles, collectors, and DJs. Old records and out-of-print recordings in particular are in much demand by collectors the world over. (See Record collecting.) Many popular new albums are given releases on vinyl records and older albums are also given reissues, sometimes on audiophile-grade vinyl.

In the United Kingdom, the popularity of indie rock caused sales of new vinyl records (particularly 7 inch singles) to increase significantly in 2006,^[81][82] briefly reversing the downward trend seen during the 1990s.

In the United States, annual vinyl sales increased by 85.8% between 2006 and 2007,^[83] and by 89% between 2007 and 2008.^[84]

Many electronic dance music and hip hop releases today are still preferred on vinyl; however, digital copies are still widely available. This is because for disc jockeys ("DJs"), vinyl has an advantage over the CD: direct manipulation of the medium. DJ techniques such as slip-cueing, beatmatching, and scratching originated on turntables. With CDs or compact audio cassettes one normally has only indirect manipulation options, e.g., the play, stop, and pause buttons. With a record one can place the stylus a few grooves farther in or out, accelerate or decelerate the turntable, or even reverse its direction, provided the stylus, record player, and record itself are built to withstand it. However, many CDJ and DJ advances, such as DJ software and time-encoded vinyl, now have these capabilities and more.

Figures released in the United States in early 2009 showed that sales of vinyl albums nearly doubled in 2008, with 1.88 million sold — up from just under 1 million in 2007.^[85] In 2009, 3.5 million units sold in the United States, including 3.2 million albums, the highest number since 1998.^[86][87]

Sales have continued to rise into the 2010s, with around 2.8 million sold in 2010, which is the most sales since record keeping began in 1991, when vinyl had been overshadowed by Compact Cassettes and compact discs.^[88]

In 2014 artist Jack White sold 40,000 copies of his second solo release, Lazaretto, on vinyl. The sales of the record beat the largest sales in one week on vinyl since 1991. The sales record was previously held by Pearl Jam's, Vitalogy, which sold 34,000 copies in one week in 1994. In 2014, the sale of vinyl records was the only physical music medium with increasing sales with relation to the previous year. Sales of other mediums including individual digital tracks, digital albums and compact discs have fallen, the latter having the greatest drop-in-sales rate.^[89]

In 2011, the Entertainment Retailers Association in the United Kingdom found that consumers were willing to pay on average £16.30 (€19.37/$25.81) for a single vinyl record, as opposed to £7.82 (€9.30/$12.38) for a CD and £6.80 (€8.09/$10.76) for a digital download.^[90] In the United States, new vinyl releases often have a larger profit margin (individual item) than do releases on CD or digital downloads (in many cases), as the latter formats quickly go down in price.

In 2015 was the sales of vinyl records up 32% to $416 million, their highest level since 1988.^[91] Meassured in number was 31.5 million vinyl records sold in 2015, and the number has increased annually ever since 2006.^[92]

Countries	2007		2008		2009		2010		2011		2012
Global Trade Value US$ (SP & LP)	$55m		$66m		$73m		$89m		$116m[93]
Australia (SP/LP)	10,000	17,996[94]	10,000	19,608[95]	10,000	53,766[96]	13,677	39,644[97]	13,637	44,876[97]	21,623	77,934[98]
Germany (SP&LP)	400,000[99]		700,000[89]		1,200,000[89]		635,000 (LPs only)		700,000 (LPs only)[100][101]		1,000,000 (LPs only)
Finland (SP&LP)	10,301[102]		13,688[103]		15,747[104]		27,515[105]		54,970[106]		47,811[107]
Hungary (LP)	2,974[108]		2,923[109]		3,763[110]		1,879[111]		8,873[112]		9,819[113]
Japan (SP&LP)	–		–		103,000		105,000[114]		–
Netherlands (LP)	–		–		51,000		60,400		81,000[115]
Spain (LP)	–		40,000		106,000[116]		97,000		141,000[117]		135,000[118]
Sweden (LP)	11,000[119]		22,000[119]		36,000[119]		70,671[119]		108,883[119]		173,124[119]
United Kingdom (SP/LP)	1,843,000	205,000	740,000	209,000	332,000	219,000	219,000	234,000	186,000	337,000[120]	–	389,000[121]
United States (LP)	988,000		1,880,000[122]		2,500,000[123]		2,800,000[124]		3,900,000[125]		4,600,000[126]
Australian single figures for 2007, 2008 and 2009 are estimated. In reality German figures are considered to be "a lot higher" due to smaller shops and online communities in Germany not using scanner cash registers.[127] One German record pressing company stated that they alone produce 2 million LPs each year.[128] In reality American figures are considered to be much higher, with one record store owner, in a New York Times article, estimating that Nielson SoundScan only tracks "about 15 percent" of total sales due to bar codes, concluding that sales could now be as high as 20 million.[129][130][131] In  Sweden, vinyl sales in 2010 were up 92% from 2009 figures,[132] and in 2011 up a further 52% from 2010 figures.[133] In 2012 vinyl sales increased with 59% from 2011 figures.[134] In  New Zealand, independent record stores in Auckland were reporting a five-fold increase in vinyl sales from 2007 to 2011.[135] In  France, the SNEP said that LP sales were 200,000 in 2008, however independent record labels said that overall sales were probably 1 million.[136] In  United States, 67% of all vinyl album sales in 2012 were sold at independent music stores.[137] Vinyl revenues were at the lowest point in its history in 2006, with a total trade value of $36 million. The 2011 figure of $116 million is higher than the 2000 figure of $109 million, but is still less than the 1997, 1998 and 1999 figures, which were all between $150 and $170 million.[93]

2012 vinyl LP charts

#[121]	US Top 10		UK Top 10
No.	Album	Artist	Album	Artist
1	Blunderbuss	Jack White	Coexist	The XX
2	Abbey Road	The Beatles	Ziggy Stardust	David Bowie
3	Babel	Mumford & Sons	Blunderbuss	Jack White
4	El Camino	The Black Keys	21	Adele
5	Sigh No More	Mumford & Sons	Lonerism	Tame Impala
6	Bloom	Beach House	Tempest	Bob Dylan
7	For Emma Forever Ago	Bon Iver	Bloom	Beach House
8	Boys & Girls	Alabama Shakes	An Awesome Wave	Alt-J
9	21	Adele	Go-Go Boots	Drive-By Truckers
10	Bon Iver	Bon Iver	The Wall	Pink Floyd

See also

• LP album
• The New Face of Vinyl: Youth's Digital Devolution (photo documentary)
• Phonograph cylinder
• Record Store Day
• Sound recording and reproduction
• Unusual types of gramophone records
• Capacitance Electronic Disc (CED)

References

Explanatory notes

Citations

Bibliography

Further reading

• Avery, Kim (April 22, 2017) Let's Get Physical: The Vinyl Resurrection

External links

Wikimedia Commons has media related to Vinyl records.

• Playback equalization for 78rpm shellacs and early LPs (EQ curves, index of record labels): Audacity Wiki
• The manufacturing and production of shellac records. Educational video, 1942.
• Reproduction of 78 rpm records including equalization data for different makes of 78s and LPs.
• The Secret Society of Lathe Trolls, a site devoted to all aspects of the making of Gramophone records.
• How to digitize gramophone records: Audacity Tutorial
• Actual list of vinyl pressing plants: vinyl-pressing-plants.com