Sound recording and reproduction

Sound recording and reproduction

Sound recording and reproduction is an electrical or mechanical inscription and re-creation of sound waves, such as spoken voice, singing, instrumental music, or sound effects. The two main classes of sound recording technology are analog recording and digital recording. Acoustic analog recording is achieved by a small microphone diaphragm that can detect changes in atmospheric pressure (acoustic sound waves) and record them as a graphic representation of the sound waves on a medium such as a phonograph (in which a stylus senses grooves on a record). In magnetic tape recording, the sound waves vibrate the microphone diaphragm and are converted into a varying electric current, which is then converted to a varying magnetic field by an electromagnet, which makes a representation of the sound as magnetized areas on a plastic tape with a magnetic coating on it. Analog sound reproduction is the reverse process, with a bigger loudspeaker diaphragm causing changes to atmospheric pressure to form acoustic sound waves. Electronically generated sound waves may also be recorded directly from devices such as an electric guitar pickup or a synthesizer, without the use of acoustics in the recording process other than the need for musicians to hear how well they are playing during recording sessions.

Digital recording and reproduction converts the analog sound signal picked up by the microphone to a digital form by a process of digitization, allowing it to be stored and transmitted by a wider variety of media. Digital recording stores audio as a series of binary numbers representing samples of the amplitude of the audio signal at equal time intervals, at a sample rate high enough to convey all sounds capable of being heard. Digital recordings are considered higher quality than analog recordings not necessarily because they have higher fidelity (wider frequency response or dynamic range), but because the digital format can prevent much loss of quality found in analog recording due to noise and electromagnetic interference in playback, and mechanical deterioration or damage to the storage medium. A digital audio signal must be reconverted to analog form during playback before it is applied to a loudspeaker or earphones.



The first devices for recording and reproducing sound were mechanical in nature and could not record arbitrary sounds such as the human voice. The automatic reproduction of music can be traced back as far as the 9th century, when the Banū Mūsā brothers invented "the earliest known mechanical musical instrument", in this case a hydropowered organ which played interchangeable cylinders automatically. According to Charles B. Fowler, this "cylinder with raised pins on the surface remained the basic device to produce and reproduce music mechanically until the second half of the nineteenth century."[1][unreliable source?] The Banu Musa brothers also invented an automatic flute player which appears to have been the first programmable machine.[2] In 1206, Al-Jazari invented a programmable musical automaton featuring humanoid musicians and drummers which could be made to play different rhythms and drum patterns if the pegs were moved around.[3] According to Charles B. Fowler, the automata were a robot band which performed "more than fifty facial and body actions during each musical selection."[1]

In the 14th century, Flanders introduced a mechanical bell-ringer controlled by a rotating cylinder. Similar designs appeared in barrel organs (15th century), musical clocks (1598), barrel pianos (1805), and musical boxes (1815).

All of these machines could play stored music, but they could not play arbitrary sounds, could not record a live performance, and were limited by the physical size of the medium. In 1796, a Swiss watchmaker named Antoine Favre described his idea for what we now call the cylinder musical box. This can be considered an early method of recording a melody, although it does not record an arbitrary sound and does not record automatically. "Playback" however is automatic. The fairground organ, developed in 1892, used a similar system of accordion-folded punched cardboard books.

The player piano, first demonstrated in 1876, used a punched paper scroll that could store an arbitrarily long piece of music. The most sophisticated of the piano rolls were "hand-played", meaning that the roll represented the actual performance of an individual, not just a transcription of the sheet music. This technology to record a live performance onto a piano roll was not developed until 1904. Piano rolls have been in continuous mass production since around 1898.[citation needed] A 1908 U.S. Supreme Court copyright case noted that, in 1902 alone, there were between 70,000 and 75,000 player pianos manufactured, and between 1,000,000 and 1,500,000 piano rolls produced.[4] The use of piano rolls began to decline in the 1920s although one type is still being made today.

The first device that could record sound mechanically (but could not play it back) was the phonautograph, developed in 1857 by Parisian inventor Édouard-Léon Scott de Martinville. The earliest known recordings of the human voice were phonautograms also made in 1857. These earliest known recordings include a dramatic reading in French of Shakespeare's Othello and music played on a guitar and trumpet.[verification needed] The recordings consist of groups of wavy lines scratched by a stylus onto fragile paper that was blackened by the soot from an oil lamp.[5] One of his phonautograms of Au Clair de la Lune, a French folk song, was digitally converted to sound in 2008.[5]


Phonograph cylinder

Frances Densmore recording Blackfoot chief Mountain Chief on a cylinder phonograph for the Bureau of American Ethnology (1916)

The first practical sound recording and reproduction device was the mechanical phonograph cylinder, invented by Thomas Edison in 1877 and patented in 1878.[6] The invention soon spread across the globe and over the next two decades the commercial recording, distribution and sale of sound recordings became a growing new international industry, with the most popular titles selling millions of units by the early 1900s. The development of mass-production techniques enabled cylinder recordings to become a major new consumer item in industrial countries and the cylinder was the main consumer format from the late 1880s until around 1910.

Disc phonograph

The next major technical development was the invention of the gramophone disc, generally credited to Emile Berliner and commercially introduced in the United States in 1889. Discs were easier to manufacture, transport and store, and they had the additional benefit of being louder (marginally) than cylinders, which by necessity, were single-sided. Sales of the Gramophone record overtook the cylinder ca. 1910, and by the end of World War I the disc had become the dominant commercial recording format. Edison, who was the main producer of cylinders, created the Edison Disc Record in an attempt to regain his market. In various permutations, the audio disc format became the primary medium for consumer sound recordings until the end of the 20th century, and the double-sided 78 rpm shellac disc was the standard consumer music format from the early 1910s to the late 1950s.

Although there was no universally accepted speed, and various companies offered discs that played at several different speeds, the major recording companies eventually settled on a de facto industry standard of nominally 78 revolutions per minute, though the actual speed differed between America and the rest of the world. The specified speed was 78.26 rpm in America and 77.92 rpm throughout the rest of the world, the difference in speeds a result of the difference in cycle frequencies of the AC power driving the synchronous motor and available gearing ratios.[7] The nominal speed of the disc format gave rise to its common nickname, the "seventy-eight" (though not until other speeds had become available). Discs were made of shellac or similar brittle plastic-like materials, played with needles made from a variety of materials including mild steel, thorn and even sapphire. Discs had a distinctly limited playing life which was heavily dependent on how they were reproduced.

The earlier, purely acoustic methods of recording had limited sensitivity and frequency range. Mid-frequency range notes could be recorded but very low and very high frequencies could not. Instruments such as the violin transferred poorly to disc; however this was partially solved by retrofitting a conical horn to the sound box of the violin. The horn was no longer required once electrical recording was developed.

The Vinyl microgroove was invented by a Hungarian engineer Peter Carl Goldmark. The vinyl microgroove record was introduced in the late 1940s, and the two main vinyl formats — the 7-inch single turning at 45 rpm and the 12-inch LP (long-playing) record turning at 3313 rpm — had totally replaced the 78 rpm shellac (sometimes vinyl) disc by the end of the 1950s. Vinyl offered improved performance, both in stamping and in playback, and came to be generally played with polished diamond styli, and when played properly (precise tracking weight, etc.) offered longer life. Vinyl records were, over-optimistically, advertised as "unbreakable". They were not, but were much less brittle and breakable than shellac. Nearly all were tinted black, but some were colored, as red, swirled, translucent, etc.

Electrical recording

RCA-44, a classic ribbon microphone

Sound recording began as a mechanical process and remained so until the early 1920s (with the exception of the 1899 Telegraphone) when a string of groundbreaking inventions in the field of electronics revolutionised sound recording and the young recording industry. These included sound transducers such as microphones and loudspeakers, and various electronic devices such as the mixing desk, designed for the amplification and modification of electrical sound signals.

After the Edison phonograph itself, arguably the most significant advances in sound recording were the electronic systems invented by two American scientists between 1900 and 1924. In 1906 Lee De Forest invented the "Audion" triode vacuum-tube, electronic valve, which could greatly amplify weak electrical signals (one early use was to amplify long distance telephone in 1915), which became the basis of all subsequent electrical sound systems until the invention of the transistor. The valve was quickly followed by the invention of the Regenerative circuit, Super-Regenerative circuit and the Superheterodyne receiver circuit, all of which were invented and patented by the young electronics genius Edwin Armstrong between 1914 and 1922. Armstrong's inventions made higher fidelity electrical sound recording and reproduction a practical reality, facilitating the development of the electronic amplifier and many other devices; after 1925 these systems had become standard in the recording and radio industry.

While Armstrong published studies about the fundamental operation of the triode vacuum tube before World War I, inventors like Orlando R. Marsh and his Marsh Laboratories, as well as scientists at Bell Telephone Laboratories, achieved their own understanding about the triode and were utilizing the Audion as a repeater in weak telephone circuits. By 1925 it was possible to place a long distance telephone call with these repeaters between New York and San Francisco in 20 minutes, both parties being clearly heard. With this technical prowess, Joseph P. Maxfield and Henry C. Harrison from Bell Telephone Laboratories were skilled in using mechanical analogs of electrical circuits and applied these principles to sound recording and reproduction.[8] They were ready to demonstrate their results by 1924 using the Wente condenser microphone and the vacuum tube amplifier to drive the "rubber line" wax recorder to cut a master audio disc.[9]

Meanwhile, radio continued to develop. Armstrong's groundbreaking inventions (including FM radio) also made possible the broadcasting of long-range, high-quality radio transmissions of voice and music. The importance of Armstrong's Superheterodyne circuit cannot be over-estimated — it is the central component of almost all analog amplification and both analog and digital radio-frequency transmitter and receiver devices to this day.

Beginning during World War One, experiments were undertaken in the United States and Great Britain to reproduce among other things, the sound of a Submarine (u-boat) for training purposes. The acoustical recordings of that time proved entirely unable to reproduce the sounds, and other methods were actively sought. Radio had developed independently to this point, and now Bell Laboritories sought a marriage of the two disparate technologies, greater than the two separately. The first experiments were not very promising, but by 1920 greater sound fidelity was achieved using the electrical system than had ever been realized acoustically. One early recording made without fanfare or announcement was the dedication of the Tomb of the Unknown Soldier at Arlington Cemetery.

By early 1924 such dramatic progress had been made, that Bell Labs arranged a demonstration for the leading recording companies, the Victor Talking Machine Company, and the Columbia Phonograph Co. (Edison was left out due to their decreasing market share and a stubborn Thomas Edison). Columbia, always in financial straits, could not afford it, and Victor, essentially leaderless since the mental collapse of founder Eldridge Johnson, left the demonstration without comment. English Columbia, by then a separate company, got hold of a test pressing made by Pathé from these sessions, and realized the immediate and urgent need to have the new system. Bell was only offering its method to United States companies, and to circumvent this, Managing Director Louis Sterling of English Columbia, bought his once parent company, and signed up for electrical recording. Although they were contemplating a deal, Victor Talking Machine was apprised of the new Columbia deal, so they too quickly signed. Columbia made its first released electrical recordings on February 25, 1925, with Victor following a few weeks later. The two then agreed privately to "be quiet" until November 1925, by which time enough electrical repertory would be available.

Other recording formats

In the 1920s, the early talkies featured the new sound-on-film technology which used photoelectric cells to record and reproduce sound signals that were optically recorded directly onto the movie film. The introduction of talking movies, spearheaded by The Jazz Singer in 1927 (though it used a sound on disk technique, not a photoelectric one), saw the rapid demise of live cinema musicians and orchestras. They were replaced with pre-recorded soundtracks, causing the loss of many jobs.[10] The American Federation of Musicians took out ads in newspapers, protesting the replacement of real musicians with mechanical playing devices, especially in theatres.[11][12]

This period also saw several other historic developments including the introduction of the first practical magnetic sound recording system, the magnetic wire recorder, which was based on the work of Danish inventor Valdemar Poulsen. Magnetic wire recorders were effective, but the sound quality was poor, so between the wars they were primarily used for voice recording and marketed as business dictating machines. In the 1930s radio pioneer Guglielmo Marconi developed a system of magnetic sound recording using steel tape. This was the same material used to make razor blades, and not surprisingly the fearsome Marconi-Stille recorders were considered so dangerous that technicians had to operate them from another room for safety. Because of the high recording speeds required, they used enormous reels about one metre in diameter, and the thin tape frequently broke, sending jagged lengths of razor steel flying around the studio.

The K1 Magnetophon was the first practical tape recorder, developed by AEG in Germany in 1935. The other major invention in sound recording in this period was the optical sound-on-film system, also generally credited to Lee De Forest. Although famous early "Talkies" like The Jazz Singer used a sound-on-disc system, the film industry rapidly adopted the optical sound-on-film system and it revolutionised the movie industry in the 1930s, ushering in the era of 'talking pictures'. Optical sound-on-film, based on the photoelectric cell, became the standard film audio system throughout the world and remains so for theatrical release prints despite attempts in the 1950s to substitute magnetic recording methods. Currently all release prints on 35mm film include an analogue optical soundtrack (usually stereo with Dolby SR noise reduction). In addition an optically recorded digital soundtrack in Dolby Digital and/or Sony SDDS form is likely to be present. Optically recorded timecode is also commonly found in order to synchronise CDROMs containing a DTS soundtrack.

Magnetic tape

Other important inventions of this period were magnetic tape and the tape recorder (Telegraphone). Paper-based tape was first used but was soon superseded by polyester and acetate backing due to dust drop and hiss. Acetate was more brittle than polyester and snapped easily. This technology, the basis for almost all commercial recording from the 1950s to the 1980s, was invented by German audio engineers in the 1930s, who also discovered the technique of AC biasing, which dramatically improved the frequency response of tape recordings. Tape recording was perfected just after the war by American audio engineer John T. Mullin with the help of Crosby Enterprises (Bing Crosby), whose pioneering recorders were based on captured German recorders, and the Ampex company produced the first commercially available tape recorders in the late 1940s.

A typical Compact Cassette

Magnetic tape brought about sweeping changes in both radio and the recording industry. Sound could be recorded, erased and re-recorded on the same tape many times, sounds could be duplicated from tape to tape with only minor loss of quality, and recordings could now be very precisely edited by physically cutting the tape and rejoining it. Within a few years of the introduction of the first commercial tape recorder—the Ampex 200 model, launched in 1948—American musician-inventor Les Paul had invented the first multitrack tape recorder, ushering in another technical revolution in the recording industry. Tape made possible the first sound recordings totally created by electronic means, opening the way for the bold sonic experiments of the Musique Concrète school and avant garde composers like Karlheinz Stockhausen, which in turn led to the innovative pop music recordings of artists such as Frank Zappa, The Beatles and The Beach Boys.

Magnetic tape allowed the radio industry for the first time to pre-record many sections of program content such as advertising, which formerly had to be presented live, and it also enabled the creation and duplication of complex, high-fidelity, long-duration recordings of entire programs. Also, for the first time, broadcasters, regulators and other interested parties were able to undertake comprehensive logging of radio broadcasts. Innovations like multitracking and tape echo enabled radio programs and advertisements to be pre-produced to a level of complexity and sophistication that was previously unattainable and the combined impact of these new techniques led to significant changes to the pacing and production style of program content, thanks to the innovations like the endless-loop broadcast cartridge.

Stereo and hi-fi

In 1881, it was noted during experiments in transmitting sound from the Paris Opera that it was possible to follow the movement of singers on the stage if earpieces connected to different microphones were held to the two ears. This discovery was commercialized in 1890 with the Théâtrophone system, which operated for over forty years until 1932.

In 1931 Alan Blumlein, a British electronics engineer working for EMI, designed a way to make the sound of an actor in a film follow their movement across the screen. In December 1931 he submitted a patent including the idea, and in 1933 this became UK patent number 394,325.[13] Over the next two years, Blumlein developed stereo microphones and a stereo disc-cutting head, and recorded a number of short films with stereo soundtracks.

Magnetic tape enabled the development of the first practical commercial sound systems that could record and reproduce high-fidelity stereophonic sound. The experiments with stereo during the 1930s and 1940s were hampered by problems with synchronization. A major breakthrough in practical stereo sound was made by Bell Laboratories, who in 1937 demonstrated a practical system of two-channel stereo, using dual optical sound tracks on film. Major movie studios quickly developed three-track and four-track sound systems, and the first stereo sound recording for a commercial film was made by Judy Garland for the MGM movie Listen, Darling in 1938.

The first movie commercially released with a stereo soundtrack was Walt Disney's Fantasia, released in 1940. The original 1941 release of this production used the "Fantasound" sound system. This system employed a separate film for the sound, which ran in synchronism with the film carrying the picture. On this sound film were four double-width optical soundtracks, three of which carried left, center and right audio while the fourth was a "control" track on which were recorded three tones which controlled the playback volume of the three audio channels. Because of the complex equipment required to present it, it was shown as a roadshow, but only in the United States. Regular releases of the film were on standard mono optical 35 mm stock until 1956 when the film was released with a stereo soundtrack using the "Cinemascope" four-track magnetic sound system.

German audio engineers working on magnetic tape are reported to have developed stereo recording by 1943, but it was not until the introduction of the first commercial two-track tape recorders by Ampex in the late 1940s that stereo tape recording became commercially feasible. However, despite the availability of multitrack tape, stereo did not become the standard system for commercial music recording for some years and it remained a specialist market during the 1950s. This changed after the late 1957 introduction of the "Westrex stereo phonograph disc", which used the groove format developed earlier by Blumlein. Decca Records in England came out with FFRR (Full Frequency Range Recording) in the 1940s which became internationally accepted and a worldwide standard for higher quality recordings on vinyl records. The Ernest Ansermet recording of Igor Stravinsky's Petrushka was key in the development of full frequency range records and alerting the listening public to high fidelity in 1946.[14]

Most pop singles were mixed into monophonic sound until the mid 1960s, and it was common for major pop releases to be issued in both mono and stereo until the early 1970s. Many Sixties pop albums now available only in stereo were originally intended to be released only in mono, and the so-called "stereo" version of these albums were created by simply separating the two tracks of the master tape. In the mid Sixties, as stereo became more popular, many mono recordings (such as The Beach Boys' Pet Sounds) were remastered using the so-called "fake stereo" method, which spread the sound across the stereo field by directing higher-frequency sound into one channel and lower-frequency sounds into the other.

1950s to 1980s

Magnetic tape transformed the recording industry, and by the late-1950s the vast majority of commercial recordings were being mastered on tape. The electronics revolution that followed the invention of the transistor brought other radical changes, the most important of which was the introduction of the world's first "personal music device", the miniaturized transistor radio, which became a major consumer luxury item in the 1960s, transforming radio broadcasting from a static group experience into a mobile, personal listening activity. An early multitrack recording made using magnetic tape was "How High the Moon" by Les Paul, on which Paul played eight overdubbed guitar tracks. In the 1960s Brian Wilson of The Beach Boys, Frank Zappa and The Beatles (with producer George Martin) were among the first popular artists to explore the possibilities of multitrack recording techniques and effects on their landmark albums Pet Sounds, Freak Out! and Sgt. Pepper's Lonely Hearts Club Band.

The next important innovation was small cartridge based tape systems of which the compact cassette, introduced by the Philips electronics company in 1964 is the best known. It eventually entirely replaced the competing formats, the larger 8-track tape (used primarily in cars) and the fairly similar 'Deutsche Cassette' developed by the German company Grundig. This latter system was not particularly common in Europe and practically unheard of in America. The compact cassette became a major consumer audio format and advances in microelectronics eventually allowed the development of the Sony Walkman, introduced in the 1970s, which was the first personal music player and gave a major boost to the mass distribution of music recordings. Cassettes became the first successful consumer recording/re-recording medium. The gramophone record was a pre-recorded playback only medium, and reel-to-reel audio tape recording magnetic tape was too difficult for most consumers and far less portable.

A key advance in audio fidelity came with the Dolby A noise reduction system, invented by Ray Dolby and introduced in 1966. A competing system dbx, invented by David Blackmer, found most success in professional audio. A simpler variant of Dolby's noise reduction system, known as Dolby B greatly improved the sound of cassette tape recordings by reducing the practical effect of the recorded hiss inherent in the narrow tape used. It, and variants, also eventually found wide application in the recording and film industries. Dolby B was crucial to the popularisation and commercial success of the compact cassette as a domestic recording and playback medium, and became a part of the booming "hi-fi" market of the 1970s and beyond. The compact cassette also benefited enormously from developments in the tape material itself as materials with wider frequency responses and lower inherent noise were developed, often based on cobalt and/or chrome oxides as the magnetic material instead of the more usual iron oxide.

The multitrack audio cartridge had been in wide use in the radio industry, from the late 1950s to the 1980s, but in the 1960s the pre-recorded 8-track cartridge was launched as a consumer audio format by Bill Lear of the Lear Jet aircraft company (and although its correct name was the 'Lear Jet Cartridge', it was seldom referred to as such). Aimed particularly at the automotive market, they were the first practical, affordable car hi-fi systems, and could produce superior sound quality to the compact cassette. However the smaller size and greater durability — augmented by the ability to create home-recorded music "compilations" since 8-track recorders were rare — saw the cassette become the dominant consumer format for portable audio devices in the 1970s and 1980s.

There had been experiments with multi-channel sound for many years — usually for special musical or cultural events — but the first commercial application of the concept came in the early 1970s with the introduction of Quadraphonic sound. This spin-off development from multitrack recording used four tracks (instead of the two used in stereo) and four speakers to create a 360-degree audio field around the listener. Following the release of the first consumer 4-channel hi-fi systems, a number of popular albums were released in one of the competing four-channel formats; among the best known are Mike Oldfield's Tubular Bells and Pink Floyd's The Dark Side of the Moon. Quadraphonic sound was not a commercial success, partly because of competing and somewhat incompatible four-channel sound systems (e.g., CBS, JVC, Dynaco and others all had systems) and generally poor quality, even when played as intended on the correct equipment, of the released music. It eventually faded out in the late 1970s, although this early venture paved the way for the eventual introduction of domestic Surround Sound systems in home theatre use, which have gained enormous popularity since the introduction of the DVD. This widespread adoption has occurred despite the confusion introduced by the multitude of available surround sound standards.

Audio components

The replacement of the thermionic valve (vacuum tube) by the smaller, cooler and less power-hungry transistor also accelerated the sale of consumer high-fidelity "hi-fi" sound systems from the 1960s onward. In the 1950s most record players were monophonic and had relatively low sound quality; few consumers could afford high-quality stereophonic sound systems. In the 1960s, American manufacturers introduced a new generation of "modular" hi-fi components — separate turntables, pre-amplifiers, amplifiers, both combined as integrated amplifiers, tape recorders, and other ancillary equipment like the graphic equaliser, which could be connected together to create a complete home sound system. These developments were rapidly taken up by Japanese electronics companies, which soon flooded the world market with relatively cheap, high-quality components. By the 1980s, corporations like Sony had become world leaders in the music recording and playback industry.

Digital recording

Graphical representation of a sound wave in analog (red) and 4-bit digital (black).

The invention of digital sound recording and later the compact disc in 1982 brought significant improvements in the durability of consumer recordings. The CD initiated another massive wave of change in the consumer music industry, with vinyl records effectively relegated to a small niche market by the mid-1990s. However, the introduction of digital systems was initially fiercely resisted by the record industry which feared wholesale piracy on a medium which was able to produce perfect copies of original released recordings. However, the industry had to bow to the inevitable, but not without using various protection system (principally Serial Copy Management System, or SCMS).

A digital sound recorder from Sony

The most recent and revolutionary developments have been in digital recording, with the development of various uncompressed and compressed digital audio file formats, processors capable and fast enough to convert the digital data to sound in real time, and inexpensive mass storage. This generated a new type of portable digital audio player. The minidisc player, using ATRAC compression on small, cheap, re-writeable discs was introduced in the 1990s but became obsolescent as solid-state non-volatile flash memory dropped in price. As technologies which increase the amount of data that can be stored on a single medium, such as Super Audio CD, DVD-A, Blu-ray Disc and HD DVD become available, longer programs of higher quality fit onto a single disc. Sound files are readily downloaded from the Internet and other sources, and copied onto computers and digital audio players. Digital audio technology is used in all areas of audio, from casual use of music files of moderate quality to the most demanding professional applications. New applications such as internet radio and podcasting have appeared.

Technological developments in recording and editing have transformed the record, movie and television industries in recent decades. Audio editing became practicable with the invention of magnetic tape recording, but digital audio and cheap mass storage allows computers to edit audio files quickly, easily, and cheaply. Today, the process of making a recording is separated into tracking, mixing and mastering. Multitrack recording makes it possible to capture signals from several microphones, or from different 'takes' to tape or disc, with maximized headroom and quality, allowing previously unavailable flexibility in the mixing and mastering stages for editing, level balancing, compressing and limiting, adding effects such as reverberation, equalisation, flanging, and much more.

Digital recording and processing software

There are many different digital audio recording and processing programs running under several computer operating systems for all purposes, from professional through serious amateur to casual user.

A comprehensive list of digital recording applications is available on the digital audio workstation page.

Digital dictation software for recording and transcribing speech has different requirements; intelligibility and flexible playback facilities are priorities, while a wide frequency range and high audio quality are not.

Voice to note

Voice-to-note refers to the capability of personal computers to be able to recognize notes that are sung, hummed, or whistled into a microphone. The pitch and duration of the notes are then calculated and converted into MIDI music files.[citation needed]

Legal status


Since 1934, sound recordings are treated differently from musical works under copyright law.[15] Copyright, Designs and Patents Act 1988 defines a sound recording to mean (a) a recording of sounds, from which the sounds may be reproduced, or (b) a recording of the whole or any part of a literary, dramatic or musical work, from which sounds reproducing the work or part may be produced, regardless of the medium on which the recording is made or the method by which the sounds are reproduced or produced. It thus covers vinyl records, tapes, compact discs, digital audiotapes, and MP3s which embody recordings.


  1. ^ a b Fowler, Charles B. (October 1967), "The Museum of Music: A History of Mechanical Instruments", Music Educators Journal (MENC_ The National Association for Music Education) 54 (2): 45–49, doi:10.2307/3391092, 
  2. ^ Koetsier, Teun (2001). "On the prehistory of programmable machines: musical automata, looms, calculators". Mechanism and Machine Theory (Elsevier) 36 (5): 589-603. .
  3. ^ Professor Noel Sharkey, A 13th Century Programmable Robot, University of Sheffield.
  4. ^ White-Smith Music Pub. Co. v. Apollo Co.209 U.S. 1 (1908)
  5. ^ a b Ron Cohen (May 29, 2009). Science News. 
  6. ^ Publication Images
  7. ^ Isom, Warren Rex (October/November 1977). "Before the Fine Groove and Stereo Record and Other Innovations .....". Journal of the Audio Engineering Society 25 (10/11). Archived from the original on May 9, 2008. Retrieved December 14, 2008. 
  8. ^ Maxfield, J. P. and H. C. Harrison. Methods of high quality recording and reproduction of speech based on telephone research. Bell System Technical Journal, July 1926, 493–523.
  9. ^ Powell, James R., Jr. The Audiophile's Guide to 78 rpm, Transcription, and Microgroove Recordings. Gramophone Adventures, Portage, MI; ISBN 0-9634921-2-8
  10. ^ American Federation of Musicians. Cf. History — 1927, 1928. "1927 — With the release of the first 'talkie', The Jazz Singer, orchestras in movie theaters were displaced. The AFM had its first encounter with wholesale unemployment brought about by technology. Within three years, 22,000 theater jobs for musicians who accompanied silent movies were lost, while only a few hundred jobs for musicians performing on soundtracks were created. 1928 — While continuing to protest the loss of jobs due to the use of 'canned music' with motion pictures, the AFM set minimum wage scales for Vitaphone, Movietone and phonograph record work. Because synchronizing music with pictures for the movies was particularly difficult, the AFM was able to set high prices for this work."
  11. ^ Canned Music on Trial, 1929 advertisement by the American Federation of Musicians — The statement from this 1929 advertisement in the Pittsburgh Press, a newspaper, said, in part:

    [picture of a can with a label saying 'Canned Music — Big Noise Brand — Guaranteed to produce no intellectual or emotional reaction whatever' ]
    Canned Music On Trial. This is the case of Art versus Mechanical Music in theatres. The defendant stands accused in front of the American people of attempted corruption of musical appreciation and discouragement of musical education. Theatres in many cities are offering synchronised mechanical music as a substitute for Real Music. If the theatre-going public accepts this vitiation of its entertainment program a deplorable decline in the Art of Music is inevitable. Musical authorities know that the soul of the Art is lost in mechanisation. It cannot be otherwise because the quality of music is dependent on the mood of the artist, upon the human contact, without which the essence of intellectual stimulation and emotional rapture is lost.
    Is Music Worth Saving? No great volume of evidence is required to answer this question. Music is a well-nigh universally beloved art. From the beginning of history, men have turned to musical expression to lighten the burdens of life, to make them happier. Aborigines, lowest in the scale of savagery, chant their song to tribal gods and play upon pipes and shark-skin drums. Musical development has kept pace with good taste and ethics throughout the ages, and has influenced the gentler nature of man more powerfully perhaps than any other factor. Has it remained for the Great Age of Science to snub the Art by setting up in its place a pale and feeble shadow of itself?
    American Federation of Musicians (Comprising 140,000 musicians in the United States and Canada), Joseph N. Weber, President. Broadway, New York City."

  12. ^ Cf. Coleman, Mark (2003) Chapter 2, "War on Canned Music".
  13. ^ GB patent 394325, Alan Dower Blumlein, "Improvements in and relating to Sound-transmission, Sound-recording and Sound-reproducing Systems.", issued 1933-06-14, assigned to Alan Dower Blumlein and Musical Industries, Limited 
  14. ^ "Decca Developed FFRR Frequency Series" — History of Vinyl
  15. ^ Gramaphone Company v. Stephen Cawardine

Further reading


External links

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