Polymers in Recording

Polymers in
Recording

Paper Cylinders

CD's

Welcome to our recording studio. All the musicians who study here at the Polydelphia Conservatory also need to know about recording technology so that they can record their recitals and other performances. Here is a look at the development of recording technology and what polymers were involved.

From Paper to Polycarbonate:
The Evolution of Recording Materials

Gregory J. Brust
The materials used for recording have changed a lot through history. The first successful sound recording was achieved by the Frenchman Leon Scott de Martinville in 1855 on what he called a "phonautograph." The phonautograph recorded sound waves onto a rotating cylinder wrapped with paper blackened by smoke. At the time, there was no way to replay the recording, but it was the first important step towards the developments to come. Through history, there have been many changes in the materials used for sound recording. Each of these changes were accompanied by an improvement in sound quality and ease of use.

In 1877 the first machine capable of recording sounds and playing them back was designed by Thomas Edison. This device was called the "tinfoil phonograph" and consisted of a rotating cylindrical drum which was wrapped in tinfoil. one could record his own voice by speaking or singing into a horn which caused a stylus or needle, to vibrate, etching the vibrations onto the foil. Edison's first recording was of himself reciting "Mary Had a Little Lamb," and although he had expected the recording to successful, was quite surprised to hear his own voice echo the recitation. Tinfoil cylinder's, though simple and inexpensive to to use were easily torn, could only be played a few times, and had a very "tinny" sound. These shortcomings led to the introduction of the next material: wax.

In 1885, Alexander Graham Bell and Charles Tainter patented the "Graphophone," a rival to Edison's phonograph. The key improvement over the Edison model was that the cylinders were made of wax instead of tinfoil. This provided longer, clearer recordings on a slightly more durable medium. This renewed Edison's interest in the phonograph, and he too adopted the wax cylinder. Wax, however, had a few drawbacks also. Wax has a tendency to melt when it gets too hot and it can also support the growth of mold and fungus. No one wants a melted or moldy record, so a new material was presented: celluloid.

Celluloid, an early plastic made from dissolved cellulose (wood), was much lighter and more durable than wax and resistant to fungus. The first celluloid cylinders, Pink Lamberts, were made by Thomas Lambert and were bright pink, hence the name. Edison finally obtained the patent rights and replaced his wax cylinders with the more durable celluloid "Blue Amberols" in 1912. These cylinders were made of bright azure blue celluloid backed with plaster of Paris. Celluloid cylinders had a few problems too The plaster of Paris can sometimes swell, warping the cylinder, and the new cylinders required a heavier diamond-stylus for the best sound. Cylinders were not the only type of records at this time, however.

In 1893, Emile Berliner introduced the "gramophone," a new phonograph which used a disc instead of a cylinder. In 1878, Edison had experimented with discs, but later decided not to use them. Berliner discs were pressed in hard rubber by a zinc master. These discs were much less expensive to produce and mass production was no problem as any number of discs could be pressed from the master, unlike cylinders which had to be engraved individually. The sound quality of Berliners was not impressive, even for the standards of the day, due to of the easily worn rubber. This flaw led to the development of Duranoid, a shellac-based plastic material which was much more resistant to wear than rubber, but quite brittle. Finally, in 1948, Columbia introduced the vinyl record which solved the brittleness problem. Vinyl is a shortened name for poly(vinyl chloride), or PVC. It is very strong and much more flexible than shellac or rubber. During the evolution of the record, another recording format was being born: magnetic recording.

In 1898 the Danish inventor Wademar Poulsen invented the first practical wire recorder. This recorder used a steel wire onto which the sounds were magnetically recorded. Within the next few years, Poulsen demonstrated the use of steel tape recorders which operated on the same principle. The sound quality of these recorders was not as good as that of records of the time, but these recorders were mainly designed for voice recording, and their ease of use made them popular for just that. Because of the brittleness of the thin steel tape and the tendency of the fine steel wire to tangle, other magnetic recording formats were sought.

The first coated magnetic tape was designed by independent inventor Fritz Pflumer in 1928. He patented a system for recording on paper coated with a magnetizable steel powder. Paper can tear quite easily, however, and wire recorders enjoyed a firm hold on the magnetic recording market until 1947 (two years before the introduction of the vinyl record) when Minnesota Mining and Manufacturing (SM) introduced a plastic based tape with an improved iron oxide coating. The plastic tape was made of what is commonly known as polyester. The scientific name for polyester is poly(ethylene terephthalate), which is used for everything from clothing to soda bottles to, apparently, magnetic tape. It is a very strong and flexible plastic making it perfect for recording tape. This tape soon became the industry standard for magnetic recording.

The first consumer prerecorded tape format was reel-to-reel, where the tape with the music was taken from one reel, manually threaded between the heads of the player, and onto a take-up reel. The stereo reel-to-reel tape was developed before the stereo record. However, music titles were limited to the classical and partisan tastes which owners of he players were assumed to have. It was only in the mid 1960's, after the successful marketing of 4-track and 8-track cartridges was rock and roll offered on reel-to-reel tapes.

The first widely used endless-loop cartridge tape was the 4 track. Developed in 1956, it was deemed "unmarketable" and remained unused until the early 1960's, when Earl "Madman" Muntz saw its potential and began producing the Muntz Stereo-Pak, a 4rack tape system for cars. Muntz, an auto dealer, thought that music should be more portable, so that one could listen to the music of his choice on the road. So Muntz refined the existing technology and marketed it as a car accessory to boost his used car sales. Bill Lear, inventor of the Learjet, rode in a car with a Muntz stereo in 1963, and was so impressed with the sound that he signed a deal to distribute Muntz systems. He installed some in his Learjets, but, being a tinkerer, began taking the players apart and found ways of improving them. This is how the 8-track was born.24

Though it was probably Muntz's 4-track which renewed Ford's interest in an in-dash cartridge system, it was the inferior 8 track which finally won favor. The 8-track, introduced in 1966 and originally only sold at such exclusive boutiques as roadside truck stops and auto parts stores, improved upon the 4-track technology by making the musical selections more easily accessed and by decreasing the probability of the tape jamming. However, these improvements brought sound quality down. By putting twice as many tracks on the same width tape, each track must be thinner and the songs can "bleed" over if the tape is misaligned. Other problems, such as tape wear and loud changes between programs led to the final demise of the 8-track, but the compact cassette was there to take its place. Cassettes, also made from coated polyester tape, were actually introduced in 1964 by by Philips, before the 8-track, but were looked upon as being inferior technology because the tape was thinner and moved slower, and therefore, fell out of favor. However, with the invention of Dolby noise reduction in 1969, the cassette's convenience, versatility, and high capacity, the inexpensive cassette found favor with he US consumers. The cassette gained control of the car sound system market, and with Sony's introduction of the Walkman in 1979, the 8-track was quickly forgotten. By 1984, sales of cassettes even exceeded that of records. Yet even cassettes have some flaws, such as some noise distortion and tangling, but compact discs solve even these problems.

Compact discs, or CDs, are made by converting a master recording to a digital format and provide clear, almost perfect resolution which cassettes cannot match. Introduced in 1982, CDs met with a lot of protest from "vinyl purists" claiming the CDs were too sterile. Yet even these voices silenced as CDs took over the recording market.

CDs are made from polycarbonate, an extraordinarily strong, clear plastic. It is the same material which is used to make "bulletproof" or "shatterproof" windows and glasses. The clarity of the plastic leads to the CDs clarity of sound, while the strength allows it to be nearly unbreakable.

Through history, changes in recording media have brought with them improvements in convenience, versatility, and especially, sound quality. Today, two formats coexist: the inexpensive, versatile cassette and the high quality CD. In the future, these traits may be combined in one format which will render them obsolete. Two such formats which are struggling for consumer acceptance are Digital Audio Cassette (DAT) or MiniDisc. Possibly an even better format will evolve. Whatever the outcome, the new media is sure to be an improvement.

Bibliography

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______, "Cylinders:A Beginners Guide,"
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Hinman, Doug and Jason Brabazon. "The Rise and Fall of the 8-Track,"
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Lavine, Abigail. "Earl Muntz, the 4-Track Madman,"
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Michalovic, Mark. "Polycarbonates," The Macrogalleria,
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______, "Polyesters," The Macrogalleria,
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______, "Magnetic Recording Chronology," Dead Recording Media,
http://www.rci.rutgers.edu/~dmorton/mrchrono.html

______, "The Wire Recorder: A Brief History," Dead Recording Media,
http://www.rci.rutgers.edu/~dmorton/wire.html

Rubinstein, Geoffrey. "Audio Recording History and Development," Jones Telecommunications and Multimedia Encyclopedia,
http://www.digitalcentury.com/encyclo/update/audiohd.html

______, "Phonograph," Jones Telecommunications and Multimedia Encyclopedia,
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Schoenherr, Steve. "Recording Technology History,"
http://ac.acusd.edu/History/recording/notes.html

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