Phonograph
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Edison cylinder phonograph ca. 1899The phonograph, or gramophone, was the most common device for playing recorded sound from the 1870s through the 1980s.
Contents [hide]
1 Terminology
2 History
2.1 The phonautograph
2.2 Phonograph theory
2.3 The first phonograph
3 British and American, and Australian language usage differences
4 Disc versus cylinder as a recording medium
5 The dominance of the disc phonograph
6 Turntable technology
6.1 Turntable construction
6.2 Turntable drive systems
7 Pickup systems
7.1 Ceramic pickups
7.2 Magnetic cartridges
8 Styli
9 Arm systems
9.1 Vertical playback systems
10 The phonograph in the 21st century
11 See also
12 External links
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Terminology
Usage of these terms is somewhat different in American English and English outside North America; see usage note below. In more modern usage, this device is often called a turntable, record player, or record changer. In the late 19th and early 20th century, the alternative term talking machine was sometimes used. The phonograph was the first device for recording and replaying sound.
The term phonograph meaning "sound writer", is derived from the Greek words ÏÏνη (meaning 'sound' or 'voice' and transliterated as phone) and γÏαÏη (meaning 'writing' and transliterated as graphe). Similar related terms gramophone and graphophone have similar root meanings. The coinage, particularly the use of the "-graph" root, may have been influenced by the then-existing words "phonographic" and "phonography," which referred to a system of phonetic shorthand; in 1852 the New York Times carried an advertisement for "Professor Webster's phonographic class," and in 1859 the New York State Teachers' Association tabled a motion to "employ a phonographic recorder" to record its meetings.
Arguably, any device used to record sound or reproduce recorded sound could be called a type of "phonograph", but in common practice it has come to mean historic technologies of sound recording.
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History
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The phonautograph
The earliest known invention of a phonographic recording device was the phonautograph, invented by Edouard-Leon Scott and patented on March 25, 1857. It could transcribe sound to a visible medium, but had no means to play back the sound after it was recorded. The device consisted of a horn that focused sound waves onto a membrane to which a hog's bristle was attached, causing the bristle to move and enabling it to inscribe a visual medium. Initially, the phonautograph made recordings onto a lamp-blackened glass plate. A later version used a medium of lamp-blackened paper on a drum or cylinder—an arrangement to which Thomas Edison's later invention would bear striking resemblance. Other versions would draw a line representing the sound wave on to a roll of paper. The phonautograph was a laboratory curiosity for the study of acoustics. It was used to determine the vibrations per second for a musical pitch and to study sound and speech; it was not widely understood until after the development of the phonograph that the waveform recorded by the phonautograph was a record of the sound wave that needed only a playback mechanism to reproduce the sound.
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Phonograph theory
Charles Cros, a French scientist, produced a theory (April 18, 1877) concerning a phonograph. Cros's work was only a theory, though, and he did not manufacture a model.
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The first phonograph
Patent drawing for Edison's phonograph, May 18, 1880.Thomas Alva Edison announced his invention of the first phonograph, a device for recording and replaying sound, on November 21, 1877 and he demonstrated the device for the first time on November 29 (he patented it on February 19, 1878; US Pat. No. 200,521). Edison's early phonographs recorded onto a phonograph cylinder using an up-down (vertical) motion of the stylus. Edison's early patents show that he also considered the idea that sound could be recorded as a spiral onto a disc, but Edison concentrated his efforts on cylinders, since the groove on the outside of a rotating cylinder provides a constant velocity to the stylus in the groove, which Edison considered more "scientifically correct". Edison's patent specified that the audio recording was embossed, and it was not until 1889 that engraved recordings were patented by Chichester Bell and Charles Sumner Tainter. They named their version the Graphophone.
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British and American, and Australian language usage differences
In British English "gramophone" came to refer to any sound reproducing machine using disc records, as disc records were popularized in the UK by the Gramophone Company. The term "phonograph" is usually restricted to devices playing cylinder records. The term "gramophone" would generally be taken to refer to a wind-up machine, and from the 1960's onwards the more common term would be "record player" or "stereo" for a complete system (most systems were stereophonic by the mid-1960's), and "turntable" for an individual component of a system that played not only records but included other sources.
In American English, "phonograph" was the most common generic term for any early sound reproducing machine, until the second half of the 20th century, when it became archaic and "record player" became the universal term for disk record machines. Emile Berliner's Gramophone was considered a type of phonograph. "Gramophone" was a brand name, and as such in the same category as "Victrola," "Zon-o-phone," "Graphophone" and "Graphonola" referring to specific brands of sound reproducing machines. Similarly, in German, "das Grammophon" (literally "the Gramophone") was the most common generic term for any sound reproducer using grooved records, hence the brand name Deutsche Grammophon.
In the Australian Vernacular, record player was the generic term; turntable was a more technical term; gramophone was restricted to the old mechanical (i.e., wind-up) players; and phonograph was used as in British English. In the compact disc era, the somewhat inaccurate retronym "black record player" became popular.
The brand "Gramophone" was not used in the USA after 1901, and the word fell out of use there. In contemporary American usage "phonograph" most usually refers to disc record machines or turntables, the most common type of analogue recording from the 1910s on. The word has survived in America based on its nickname form, "Grammy", in the Grammy Awards.
Strictly speaking, the gramophone is the machine reproducing sound from an engraved archive, whereas a phonograph is a machine that captures sound onto an engraved archive, i.e., a lathe.
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Disc versus cylinder as a recording medium
Disc recording is inherently neither better nor worse than cylinder recording in potential audio fidelity.
Recordings made on a cylinder remain at a constant linear velocity for the entirety of the recording, while those made on a disc have a higher linear velocity at the outer portion of the groove compared to the inner portion.
Edison's patented recording method recorded with vertical modulations in a groove. Berliner utilized a laterally modulated groove.
Though Edison's recording technology was better than Berliner's, there were commercial advantages to a disc system:
The disc could be easily mass produced by molding and stamping, and required less storage space for a collection of recordings.
The heavy cast-iron turntable acted as a flywheel and helped to maintain a consistent rotational velocity. The cylinder machine, lacking this greater rotational inertia, was susceptible to musical pitch fluctuations, and required more mechanical adjustment and maintenance to avoid this impairment.
Berliner successfully argued that his technology was different enough from Edison's that he did not need to pay royalties on it, which reduced his business expenses.
Through experimentation, in 1892 Berliner began commercial production of his disc records, and "gramophones" or "talking-machines". His "gramophone record" was the first disc record to be offered to the public. They were five inches (12.7 cm) in diameter and recorded on one side only. Seven-inch (17.5 cm) records followed in 1895. By 1901, ten-inch (25.0 cm) records being sold by the Victor Talking Machine Company, and Berliner had sold his interests. By 1908, double sided disc recorded records became demanded by the public, and cylinders fell into disfavor. Edison felt the commercial pressure for disc records, and by 1912, though reluctant at first, his movement to disc records was in full swing.
From the mid-1890s until the early 1920s both phonograph cylinder and disc recordings and machines to play them on were widely mass marketed and sold. The disc system gradually became more popular due to its cheaper price and better marketing by disc record companies. Edison ceased cylinder manufacture in the fall of 1929, and the history of disc and cylinder rivalry was concluded.
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The dominance of the disc phonograph
Berliner's lateral disc record was the ancestor of the 78 rpm, 45 rpm, 33â
rpm, and all other analogue disc records popular for use in sound recording through the 20th century. See gramophone record.
Christmas 1925 brought improved radio technology and radio sales, bringing many phonograph dealers to financial ruin. With efforts at improved audio fidelity, the big record companies succeeded in keeping business booming through the end of the decade, but the record sales plummeted during the Great Depression, with many companies merging or going out of business. Booms in record sales returned after World War II.
A phonograph circa 1979The turntable remained a common element of home audio systems well after the introduction of other media such as audio tape and even the early years of the compact disc. They were not uncommon in home audio systems into the early 1990s.
By the turn of the 21st century, the turntable had become a niche product. Nevertheless, turntables and records continue to be manufactured and sold as of 2006, albeit in very small quantities when compared to the disc phonograph's heyday.
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Turntable technology
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Turntable construction
Inexpensive record players typically used a flanged steel stamping for the turntable structure. A rubber disc would be secured to the top of the stamping to provide traction for the record, as well as a small amount of vibration isolation. The spindle bearing usually consisted of a bronze bushing. The flange on the stamping provided a convenient place to drive the turntable by means of an idler wheel (see below). While light and cheap to manufacture, these mechanisms had low inertia, making motor speed instabilities more pronounced.
For the serious listener, turntables made from heavy aluminum castings were offered. Typically, they were machined on a lathe and balanced, operating with negligible vibration. Like the stamped steel turntables, they, too, were topped with rubber. Due to the increased mass, they usually employed ball bearings or roller bearings in the spindle for low friction. While some used idler wheel drive, most were intended for belt or direct drive. The high mass and inertia of such turntables helped keep the speed constant, even if the motor exhibited cogging effects.
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Turntable drive systems
Most turntables employ an idler-wheel drive, belt drive or direct drive system to rotate the turntable platter:
Idler-wheel drive system
Earlier designs used a rubberized idler-wheel drive system. However, wear and decomposition of the wheel, as well as the direct mechanical coupling to a vibrating motor, introduced low-frequency noise ("rumble") and speed variations ("wow and flutter") into the sound. These systems generally used a synchronous motor which ran at a speed synchronized to the frequency of the AC power supply. Portable record players typically used an inexpensive shaded-pole motor. At the end of the motor shaft there was a stepped driving capstan; to obtain different speeds, the rubber idler wheel was moved to contact different steps of this capstan. The idler was pinched against the bottom or inside edge of the platter to drive it.
Until the 1980s, the idler-wheel drive was the most common on turntables, except for higher-end audiophile models.
Belt drive system
Belt drives brought improved motor and platter isolation compared to idler-wheel designs. Motor noise heard as low-frequency rumble was much reduced. Many belt-drive turntables having multiple speeds used a simple mechanical system to change speeds, using a mechanism to move the belt between different-sized pulleys on the motor shaft. For electronic speed control, it is difficult to design multiple-speed synchronous motors; consequently, DC servomotors with electronics providing speed control have gained favor. On the most sophisticated designs, optical sensors on the platter are used to ensure the speed of the platter remains stable. Many platters have a continuous series of strobe markings machined or printed around their edge to provide optical pulses to these speed-control systems. Viewing these markings in artificial light at mains frequency produces a stroboscopic effect, which can be used by the operator to verify rotational speed. DC servomotors rotate in steps rather than continuously. This is referred to as 'cogging', and can add noise during playback. Helical armature motors can be used to overcome this. Problems with belt instability and deterioration have largely been solved by use of modern elastic polymers.
Direct drive system
Direct drive turntables drive the platter directly without utilizing intermediate wheels, belts, or gears as part of a drive train. The platter functions as a motor armature. This requires good engineering, with advanced electronics for acceleration and speed control. Matsushita's Technics division introduced the first commercially successful direct drive platter, model SP10, in 1969. The Technics SL-1200 turntable, introduced in 1972, is one of the most successful direct drive turntables ever produced. Its rapid acceleration up to speed, quartz locked speed control, electric braking system and its reliability made it a favourite with radio stations and disc jockeys across the world. It became particularly popular with the disc jockeys who used it for beatmixing because it has a variable pitch control (first a knob and then a slider on the Mk 2), allowing variations of the rotational speed above and below the usual 33 and 45 rpm settings. The SL-1200 turntable (in Mk 2 and Mk 5 guises) is still in production as of 2006 - a remarkable achievement in an increasingly digital world.
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Pickup systems
cartridge[edit]
Ceramic pickups
Another major component is the pickup or cartridge. Early electronic phonographs used a piezo-electric quartz crystal for pickup, where the mechanical movement of the stylus in the groove generates a proportional electrical voltage by creating stress within the crystal. Crystal pickups are relatively robust, and yield a good level of signal which requires only a modest amount of amplification. A crystal's output tends not to be very linear, that is, it introduces unwanted distortion. It is difficult to make a crystal pickup suitable for stereo reproduction, as the stiff coupling between the crystal and the stylus prevents close tracking of the needle to the groove modulations. This tends to increase wear on the record, and introduces distortion.
The next development was the ceramic cartridge, which was also a piezoelectric transducer like the crystal, but because it was more sensitive, could be made with greater compliance (the ability to ride the undulations of the groove without distorting or jumping out of the groove). This also allowed ceramic stereo cartridges to be made. The ceramic cartridge became standard in most phonographs, except for the better high-fidelity (or "hi-fi") systems.
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Magnetic cartridges
In high-fidelity systems, crystal and ceramic pickups have been replaced by the magnetic cartridge, using either a moving magnet or moving coil. In the moving magnet system, the stylus carries a tiny permanent magnet, which is positioned between two sets of fixed coils (in a stereophonic cartridge). As the magnet vibrates in response to the stylus following the record groove, it induces a tiny current in the coils. This current is fed to an amplifier which boosts the signal, and then to a loudspeaker. Because the magnet is so light, and is not coupled mechanically to the coils, the stylus follows the groove far more gently and faithfully, requiring less tracking force (the downward pressure on the stylus). Moving coil systems are generally more expensive and are preferred by some audiophiles. Here the coils are attached to the stylus, and move within the field of a permanent magnet. Magnetic cartridges provide a much lower output than a crystal or ceramic pickup, in the range of a few millivolts, thus requiring a preamplifier stage, as well as additional equalization to correct the response of the cartridge over the audio frequency range. Moving-coil cartridges generate an even smaller signal, of a few hundred microvolts, and require additional preamplification. Electrical noise induced by power lines or other EMI are attenuated by various methods, including electromagnetic shielding in the signal cables connecting the pickup to the amplifier.
Historically, most stereo high-fidelity component systems (preamplifiers or receivers) that accepted input from a phonograph turntable had separate inputs for both ceramic and magnetic cartridges (typically labeled "CER" and "MAG"). Most systems today, if they accept input from a turntable at all, are configured for use only with magnetic cartridges; ceramic cartridges are for all practical purposes completely obsolete.
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Styli
The stylus typically has either a hemispherical (known as "conical") diamond tip for playing monophonic recordings or for or rugged use, or an elliptical diamond tip for playing stereo or binaural records. Specially-profiled tips (such as "line contact" tips) are intended to track the record groove even more accurately than an elliptical tip, but styli with such tips are expensive.
Most cartridges have an aluminum cantilever, the arm that connects the the stylus to the magnet or pickup coils; some very expensive models have ruby, boron, or carbon fiber cantilevers chosen for their exceptional stiffness.
DJs use the more rugged conical styli due to the frequent reversals of direction involved in scratching and back-cueing - these activities also require a very rugged cantilever. Magnetic cartridge manufacturers usually provide a specialised range of styli for DJ use.
Phonograph recordings are made with high frequencies boosted. This reduces background noise, including clicks or pops, and also conserves the amount of physical space needed for each groove, by reducing the size of the larger low-frequency undulations. During playback the high frequencies are rescaled to their original level. This is accomplished in the amplifier with a "PHONO" input that incorporates standardized RIAA equalization circuitry.
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Arm systems
adjustable counterweightBasic arm design has changed relatively little. S-Type tonearms can be found on even the 1925 Victor Orthophonic phonograph. Originally, even though the tonearm was light for earlier electric pickups, the full weight rested on the record. Right through to the crystal pickup, this was required to create sufficient tracking force to follow the grooves adequately with relatively stiff styli. Naturally, record wear was not given much consideration. With the advent of the better technologies, including more powerful rare-earth magnetic cartridges, far lighter tracking forces became possible, and a balanced arm came into use. Most use a counterweight to offset the weight of the arm. A calibrated dial on the weight provides for quick change of stylus pressure. Stylus pressures of 1 to 2 grams are currently the standard for high-fidelity turntables, while pressures of up to 5 grams are common for DJ use.
Tonearms are prone to two types of tracking errors that can affect the sound. As the tonearm tracks the groove, the stylus drags tangent to the disc surface and resistance along the arm combines to create a horizontal skating force towards the center of the disc. Modern arms provide an antiskating mechanism, using springs, hanging weights or magnets, to offset this force, so as to make the net horizontal force near zero. The second error occurs as the arm sweeps in an arc across the disc, causing the angle between the cartridge head and groove to change slightly. A change in angle, albeit small, may have an audible detrimental effect by creating a differential force on the groove walls. Making the arm longer to reduce this angle is a partial solution, but less than ideal, because the arm would need to be of infinite length to reduce angular errors to zero. Some arms (such as the Garrard "Zero" series) have been manufactured with a parallelogram arrangement which pivots the cartridge head on the arm to maintain a constant angle.
Typical phonograph tonearmIf the arm is not pivoted, but instead travels horizontally along a radius of the disc, there is no skating force and no cartridge angle error. The arm is driven along a linear track using an electronic servomechanism to position it properly. Bang & Olufsen developed the first practical system with its model Beogram 4000 in 1972. Early Edison phonographs had utilized similar spring-powered drives to carry the stylus across the record at a pre-determined rate. In practice, the linear tracking system is not widely used today due to its complexity and attendant expense. However, some of the most sophisticated systems do employ this technique. It is nearly ideal, as the stylus replicates the motion of the recording lathe when the master recording was cut.
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Vertical playback systems
In the early 1980s, an upright (front loading) record playing music centre appeared, in which the record was placed in a door which hinged downwards to accept it. The door retracted automatically and the record was spun in the vertical plane. A pair of linear-tracking arms traversed the disk, one on each side, so that both sides could be played without stopping. The system was mechanically and electronically complex. It worked, but the system was aimed at the mass market and had only mediocre sound quality. The large size of the hinged door made it vulnerable to damage, and the retraction motor was barely able to lift its weight, especially after some years of use. ELPJ has recently revived this design with its laser turntable.
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The phonograph in the 21st century
Turntables continue to be manufactured and sold into the 21st century, although in small numbers. Whilst there are many audiophiles who still prefer vinyl records played on record players compared to digital music sources such as compact disc for their perceived fidelity, these represent an enthusiastic minority of listeners. The quality of the available record players, tonearms, and cartridges has continued to improve, despite the diminishing market.
Phonograph turntables at a radio station, 2003
Updates to the 1970s era Technics SL-1200, have remained an industry standard for DJs to the present day. Turntables and vinyl records remain popular in mixing (mostly dance-oriented) forms of electronic music, where they allow great latitude for physical manipulation of the music by the DJ.
In hip hop music, the turntable is used as a musical instrument. Manipulation of a record as part of the music rather than for normal playback or mixing, is called turntablism. The basis of turntablism and its best known technique is scratching, pioneered by Grand Wizard Theodore. It was not until Herbie Hancock's "Rockit" in 1983 that the turntablism movement was recognized in popular music outside of a hip hop context. See list of turntablists for more influential turntablist artists.
The laser turntable, which uses a laser as the pickup instead of a stylus in physical contact with the disk, was conceived of in the late 1980s, although early prototypes were not of usable audio quality. Practical laser turntables are now being manufactured by ELPJ. They are favoured by record libraries and some audiophiles since they eliminate physical wear completely. The turntable remains the preferred sound source in some high end audio systems.
Experimentation is in progress in retrieving the audio from old records by scanning the disc and analysing the scanned image, rather than using any sort of turntable, by Ofer Springer at the Hebrew University of Jerusalem.
Many audiophiles believe that a turntable in conjunction with a high-quality tonearm and phonograph cartridge produce better sound than a CD player. This is based on a subjective evaluation of recorded music and not necessarily on technical measurements of turntables versus CD players. Notable turntables (and this is not an extensive list) include the Linn LP-12, the Sota Cosmos, the Immedia RPM-2, the VPI TNT and the SME Model 30. Although mostly replaced by the Compact Disc in the early 1980's, record albums have increased in production recently and are available through numerous sources. Many audiophiles belive that all-analog recordings, made using a traditional tape recorder, have a more natural sound than digital recordings. Again, this is based on empirical observation and not necessarily on technical specifications. Most high-quality turntables use an elastic belt to drive the rotating platter from an electric motor; although, the Rockport Sirius uses a linear induction motor with no physical connection to the platter. Many turntables, such as the Rega Planar series, use a fixed plinth with the motor and bearing attached to the same flat surface, usually constructed of wood, metal or acrylic. Other turntables use a suspended chasis with the bearing is attached to a separate plinth from the motor, suspended by a spring or other elastic connection (such as a series of O-rings). Bearings generally use an oil film to lubricate a metal ball connected to the platter by a spindle. More esoteric designs use an air bearing, where the spindle is supported by a high pressure flow of air. The evaluation of the "best" turntable design is very subjective and often based more on listening experience than on technical measurement; although, many would argue with that. Audiophile quality turntables start at a few hundred dollars and range upwards of $100,000 depending on the complexity and quality of design. Many non-audiophiles believe that one gets dimishing returns with an increase in price, where a tuntable costing $1000 would not sound twice as good as a turntable costing $500. However, many audiophiles believe the exact opposite, that sound quality more than doubles with a doubling of price. Again, the observations are very subjective.