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Analogue disc record

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Manufacturers put records inside protective and decorative cardboard jackets and an inner paper sleeve to protect the grooves from dust and scratches.  The 12-inch (30 cm) LP vinyl album <em>[[Heaven and HellEnlarge

Manufacturers put records inside protective and decorative cardboard jackets and an inner paper sleeve to protect the grooves from dust and scratches. The 12-inch (30 cm) LP vinyl album [[Heaven and Hell

by Black Sabbath is an example, showing the South Korean version of the 33⅓ rpm record from 1980 or 1983.]]

An analogue disc record is a type of sound recording medium, commonly called a gramophone record in British English or a phonograph record in American English. Analogue disc recording was the main technology used for storing recorded sound in the 20th century. Before the advent of digital recording, the term 'analogue' was never applied, all recordings being analogue.

Whilst a 78rpm record is brittle and relatively easily broken, both the LP record and the 45 rpm single records are made from vinyl plastic which is flexible and unbreakable in normal use. 78s come in a variety of sizes, the most common being 10 inch (25cm) and 12 inch (30cm) diameter, and these were originally sold in either paper or card covers, generally with a circular cutout allowing the record label to be seen. LPs usually come in a paper sleeve within a colour printed card jacket which also provides a track listing. 45 rpm singles and EPs (Extended Play) are of 7 inch (17.5cm) diameter, the earlier copies being sold in paper covers. Grooves on a 78rpm are much coarser than the LP and 45.

Other common names included record, disc, black disc and (more informally) platter or sides. 12-inch (30.5 cm)33⅓ rpm vinyl discs were often called long-playing records, albums, or LPs (the latter being a trademark of Columbia Records, adopted into common parlance). The term vinyl or vinyl record began to be used in the 1980s, particularly when drawing distinctions between records and compact discs (CDs), though it should be noted that before the 1950s most disc records were made of materials other than vinyl.

An analogue disc record is a flat disc with inscribed spiral grooves, in which the playback process begins with the direct mechanical motion of a stylus riding within the groove as the disc rotates.

Table of contents
1 Introduction
2 Early history
3 Post-war formats
4 The analogue record mastering and pressing process
5 Disc limitations
6 The "War of the Speeds"
7 Record changers and albums
8 The analogue record in the era of digital technology
9 See also
10 Further reading

Introduction

The analogue disc record is an audio storage medium, most commonly used for preserving music. A gramophone record almost always consists of a disc engraved with a single concentric spiral groove on each side of the disc, in which a stylus or needle runs, from the outside edge towards the centre. (A small number of early phonograph systems and radio transcription discs started the groove from the inside rather than the edge of the disc, and a small number of novelty records were manufactured with multiple separate grooves.) The record spins at a certain fixed speed, while the needle is held on a mobile arm, which gradually moves toward the centre of the record as it follows the spiral. Since the late 1910s, both sides of the record have usually been used for playing surfaces.

By the early 1990s digital media such as the compact disc surpassed the analogue disc in popularity, but analogue discs continue to be made (although in very limited quantities) into the 21st century, particularly for DJs doing live remixes.

Early history

Recording on disc as opposed to phonograph cylinder had been contemplated and experimented with by such inventors as Charles Cros, Thomas Edison, and Chichester Bell, but the first to actually develop usable disc record technology was Emil Berliner, a German working in Washington, DC, in 1884. He got patents in Berlin and Washington, DC for the record and the gramophone in 1887.

Berliner recordEnlarge

Berliner record

plays at about 55 rpm.]]

The first disc recordings for phonographs or gramophones were commercially marketed in 1895. They gradually overtook the earlier phonograph cylinder as the dominant medium of recorded sound by the 1910s, as they were more economical to produce, less fragile, and easier to store.

Early analogue disc records were originally made of various materials including hard rubber. In the early 20th century earlier materials were largely replaced by a rather brittle formula known as "shellac", actually a mixture of shellac resin and cotton or other fiber. The mass production of shellac records began in 1898 in Hanover, Germany. Shellac records were the most common until about 1950. Earliest speeds of rotation varied widely, but by 1910 records rotating at or about 78 or 80 times in one minute became standard, with 78 rpm becoming the standard in the late 1920s. This gave a common name for such records as 78s (or "seventy-eights"). This term did not come into use until after World War II when a need developed to distinguish the 78 from other newer disc record formats. Earlier they were just called records, or when there was a need to distinguish them from cylinders, disc records. Standard records was also used, although the same term had also been used earlier for two-minute cylinders.

In the 1890s the early recording formats of discs were usually seven inches (18cm) in diameter. By 1910 the 10-inch (25 cm) record was by far the most popular standard, holding about three minutes of music or entertainment on a side. 12-inch records were also commercially sold, mostly of classical music or operatic selections, with five minutes of music per side.

Such records were usually sold separately, but sometimes in collections held in paper sleeves in a cardboard or leather book, similar to a photograph album, and called record albums. Also, empty record albums were sold that customers could use to store their disc records in.

Many records from the mid-1950s and later sported this LP logo indicating their slower speed of 33⅓ [[rpm
.]]

Post-war formats

After World War II, the "78" was replaced by two competing formats: the 33⅓ rpm (often just referred to as to 33 rpm), and the 45 rpm. The 33⅓ rpm LP (for "long play") format was developed by Columbia Records and marketed in 1948. RCA Victor had developed the 45 rpm format years earlier but had not marketed it until 1949, in response to Columbia. Both types of new disc used narrower grooves, intended to be played with a smaller stylus, than the old "78s", so the new records were sometimes called Microgroove. All of these companies agreed to a common recording standard for improving quality called RIAA equalization.

The older 78 format continued to be mass produced along side the newer formats into the 1950s (and in a few countries, such as India, into the 1960s).

About the same time the most common substance for making disc records became vinyl. All speeds of records were made in various sizes, mainly 7, 10 and 12 inches (18,20.5 and 30.5 cm aprox.) diameter; the 7-inch being most common for the 45rpm, the 10-inch for the 78 (and the first few years of 33⅓ production), and the 12-inch for the 33 from the mid 1950s on.

45 rpm records, like this one from 1955, often held a <em>single</em> - one especially popular tune from a particular artist - with a <em>flip side</em>, a bonus for ownersEnlarge

45 rpm records, like this one from 1955, often held a single - one especially popular tune from a particular artist - with a flip side, a bonus for owners

Disc records were extremely popular in their heyday, despite their well-known weaknesses. Throughout most of their period of popularity audio quality was below the best technically possible, but disc records were cheap to manufacture, and easy for the buyer to store and play back.

In addition to the formats mentioned, numerous less common formats were also produced, often as gimmicks. See: Unusual types of analogue disc record

The analogue record mastering and pressing process

Recording the disc

For the first several decades of disc record manufacturing, sound was recorded directly on to the master disc (also called the matrix, sometimes just the master) 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 on these master discs were soft wax, later on a harder lacquer was used.

Mass producing records

The soft master would then usually be electroplated with a metal, commonly a nickel alloy. When this metal was removed from the master, it would be a negative master (in some companies' terminology, this was called the master; note difference from master disc above). In the earliest days the negative master was used as a mold to press records sold to the public, but as demand for mass production of records grew, another step was added to the process.

The negative master mold is used to create metal positive discs, each called a mother or matrix. These mothers would then in turn be used to make more negatives, each called a stamper. The stampers would be used as the molds for the discs sold to the public. The advantages of this system over the earlier more direct system included ability to make more records more quickly by having multiple stampers pressing records at the same time, more records could be pressed from each record since much used molds would eventually wear out, and spare mothers as back ups.

Disc limitations

Shellac 78s were extremely brittle and would break into several pieces if dropped. This was a very common accident and even the most careful owners usually lost some records to breakage.

Vinyl records were less subject to breakage. However, the vinyl material was an effective insulator and very prone to acquiring a static charge and attracting dust, which was very difficult to remove completely. The soft material was easily scratched. Dust and scratches caused audio clicks and pops. In extreme cases, they could cause the needle to skip over a series of grooves, causing the player to skip over a segment of the audio track; or, worse yet, cause the needle to skip backwards, creating a "locked groove" that would repeat the same portion of track over and over again. Locked grooves were not uncommon and were even heard occasionally in broadcasts. Locked grooves formed the subject of jokes ("Machines never make a mistake... make a mistake... make a mistake...") and became a common metaphor (a repetitious complainer might be accused of being "a broken record").

Vinyl records were easily warped out of shape by heat, improper storage, or manufacturing defects such as excessively tight plastic shrink wrap on the album. 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.

Audiophiles would take great care of their records, often playing them on expensive equipment to get the best sound and impart the least wear to the disc. However, even with the best of care, keen ears could often detect slight surface noise and audio degradation after two to five playings of a vinyl record. Repeated use degraded the audio quality further.

As a practical matter, records provided more than adequate sound quality when treated with care and replaced after a reasonable number of playings. They were the music source of choice for radio stations for decades, and the switch to digital music libraries by radio stations has not produced a noticeable improvement in sound quality. Casual ears cannot detect a difference in quality between a CD and a clean new LP played on good equipment, and some aficionados believe that under the very best conditions LP sound is superior to CD. The limitations of recording and mastering techniques had a greater impact on sound quality than the limitations of the record itself, at least until the 1980s.

Records were easy and inexpensive to manufacture, so they could be mass-produced. Also, with the advent of long-playing records, the album cover became more than just packaging and protection, and album cover art became an important part of the music marketing and consuming experience.

ColumbiaEnlarge

Columbia

and RCA duked it out in the center of the record. Some turntables included spindle size adapters, but other turntables required snap-in inserts like this one to adapt RCA's larger 45 rpm spindle size to the smaller spindle size available on nearly all turntables. An incorrectly centered record makes a warbling sound.]]

The "War of the Speeds"

Columbia introduced the 33⅓ rpm LP (long playing) record in 1948. In what has since become an all-too-familiar scenario, their biggest competitor, RCA, deliberately introduced an incompatible format as a competitive marketing maneuver. In addition to having different speeds (33⅓ vs 45), the systems used different record sizes (12" and 10" vs 7") and a different-sized hole in the center. RCA apparently hoped that consumers would like a system that offered about the same amount of recorded material per disc as the traditional 78s, in a lightweight, compact, higher-fidelity format. Their main consumer offering was a compact, inexpensive 45 changer which had no speakers or amplifier, but was intended to plug into the audio jacks of the then-common console radios and televisions.

RCA's sales declined and in 1950 they capitulated and began using the Columbia format.

By then, phonograph manufacturers had figured out how to cope with the nuisance. Backward compatibility with 78-rpm was important, and if you had to include a two-speed mechanism it wasn't that much more costly to include three. The technical characteristics of 33's and 45's were similar enough to allow use of the same cartridge, stylus, and electronics. By the 1950s most consumer phonographs offered three speeds (78, 45, 33); a single cartridge with a flipover stylus (a single shaft with appropriate stylus for 78's on one side and for microgroove records on the other); and a variety of awkward spindle-size adapters.

Record changers and albums

78-rpm records of popular music were commonly 10" (25.4 cm)in diameter with a single song on each side. Classical music was commonly recorded on multiple 12" disks. Sets of disks — classical works, collections of popular music, and Broadway shows — were frequently packaged in what were literally albums. These were stiff cardboard boxes containing a bound set of four to six tough paper envelopes, each holding a disc. These envelopes could be turned like pages of a book. During the 1950s, most popular music was sold in the form of a single 10" 78-rpm record or a single 7" 45-rpm record. Popular music was also sold in the form of collections — eight songs by Frank Sinatra on a 10" LP, or twelve on a 12" LP. These single LPs corresponded an entire album of 78s and were therefore referred to as albums.

The limited playing time of 78 rpm records led to the development of record changers, which allowed stacks of several records to be loaded on a spindle and automatically played in sequence. The purely mechanical mechanisms were ingenious, and most of them were capable of automatically measuring the size of each record as it dropped and positioning the tone arm in the lead-in groove, so that stacks of 7", 10", or 12" records could be played automatically. This also led to the invention of the jukebox.

Record changers were provided in most mid-priced consumer phonographs of the 1950s through 1970s. Audiophiles disdained them because of the compromised fidelity resulting from changes in tone arm angle with the height of the stack, and concerns about changers' seemingly rough treatment of discs (particularly slight but cumulative damage to the spindle hole). Changers became rarer in the 1980s.

The numbering of the sides of the discs in albums and boxed sets of LPs is explained by the fact that they were designed to be played on changers. After the discs were stacked and one side of each disc played, the stack would be turned over together as a unit and replaced on the changer. Thus, to be heard in the proper sequence, the discs of a four-disc set would contain, respectively, "sides" 1 & 8, 2 & 7, 3 & 6, and 4 & 5.

The analogue record in the era of digital technology

Starting in the 1980s, vinyl records were gradually replaced in mainstream music consumer markets with the compact disc (CD). Vinyl records continue to be manufactured and sold today, although it is considered to be a niche market comprised of audiophiles, collectors, and disc jockeys (DJs). Punk and hardcore bands also often produce their albums and singles on vinyl.

Many audiophiles dispute the superiority of CDs. The lack of hiss or background crackling is not an inherent quality of CDs, but is dependent on the quality of the original recording. Also the quality and clarity of the sound is very much dependent on the quality of the reproduction equipment, for example the DAC (digital to analog converter).

Some feel that there are inherent limitations with the 44.1kHz sampling rate used for CDs, which may not be a high enough sampling rate to capture subtle phase differences of the psychoacoustic placement of sound in the stereo image. CD recording is limited to the little more than the frequency range of human-audible sounds, and many feel that this makes CD-recorded sound ÑÑcoldÒÒ: the theory behind being that non-audible sounds add to analogue recording a ÑÑwarmthÒÒ lacking in CDs. To try to solve this specific problem various solutions have been proposed, like CD players that try to digitally extrapolate non-audible sounds from the recording, and switching to DVD-Audio with its wider frequency range.

More esoteric audiophiles may also state, that instead of just "reproducing" the sound as a CD would, the analogue disc record is able to capture the "real" sound and continue its natural distribution when the record is played.

The background noise one hears on a vinyl record has been compared to the patina of an oil painting -- a part of the work, not an imperfection to be eliminated; moreover, it has been claimed that some pre-CD recordings were made with this patina in mind. To further cloud the issue, some pop music released on CD has had crackles and hiss added artificially, for effect. See Lo-fi. Laser turntables which vacuum clean the vinyl surface before reading it are said to give CD-like clean sound reproducing while preserving all the warmth of analog recording, but they are at the moment extremely expensive for home use.

One argument in favour of vinyl albums is that older recordings were made specifically for vinyl, with equipment specifically calibrated to produce a good-sounding LP. Then, when CDs were introduced, the albums were hastily remastered, and the CD does sound inferior. This is not a fault of the digital medium itself, but rather that the recording was not made to take full advantage of it. Recently, many albums from the pre-CD era (around 1990 or so tends to be the cutoff for when CDs became "the standard" to which recordings were targetted) have been carefully remastered, and sound as good as the original LPs.

See also

Further reading