Electronic music has existed, in various forms, for more than a century. Between the time that recording sounds was first made possible and the computer technology of today, a vast amount of change has occurred. Technology has been developed for creating sounds, for recording sounds, composing, and for altering sounds. Some technology involved electronics, but some important conceptual changes that did not depend on electronics still had a profound impact on the advent of electronic music. The experimentation with technology was occurring in many countries simultaneously, sometimes for different purposes. Throughout the last century, musicians, artists, scientists, inventors, and businessmen each had interest in the progress of technology, and cross-pollination was and continues to be quite common. For this reason, part of the history necessarily includes advances in other fields. The first quarter of the 20th Century was often referred to as the Mechanical Age, which overlapped and shifted into the Electronic Age. The last quarter of the 20th Century marked the beginning of the revolutionary Computer Age, in the throes of which we now find ourselves.

As musicians, it is notable that some of the finest musicians and most highly acclaimed institutions are largely responsible for the progress made in the field of electronic music. This is not an isolated crowd; rather, it includes celebrities such as Stokowski, Boulez, Stockhausen, and institutions including Columbia University, Princeton University, and Stanford University, as well as many highly active and advanced studios in Europe. The beginnings of true electronic music were received with such profound appreciation. Time Magazine and the Today show featured the experimental composers and their works, an indication that they were well-received by conventional musicians.

The people involved in electronic music today still come from many different directions, and not solely from conventional classical, or art music academia. This fact may be part of the reason that classically trained performers have less awareness of electronic music than would be warranted considering its history. These classical performers tend to still be taught pre-20th Century and early 20th Century music, and the latter half of the century is largely ignored. As one can deduce from a brief look at the history of electronic music, the progress represents a natural course, a continuum, of progress of classical music. Many believe as flutist Patricia Spencer does, that the exploration of electronic instruments represents "the development of a new instrument." [17]  Its inclusion in the current pedagogy is quite appropriate; in fact, one would be ill advised to exclude teaching this music, seeing as it represents the current trend and profoundly affects the future of classical music. Proponents of electronic music today understand the importance of knowing the history, as exemplified in this statement by flutist Elizabeth McNutt, "A knowledge of the history brings greater understanding, and we are more forgiving." [18]  Mario Davidovsky, one of the most important living figures involved in electronic music, describes the effect electronic music had on his acoustic writing: "and then when I would return to write chamber music and orchestral music, I was incredibly influenced by all these new ideas of how sound could behave." He also understands this music to have a large impact on all contemporary composers: "We can say that 20th Century music has been greatly influenced by electronic music, whether the composers were using electronic instruments or not." [19] 

The history I am presenting includes advances in music technology in general, some significant works and composers, and does not focus on flute music in particular. Interestingly, the composers of the pieces analyzed in my dissertation have their own place in this history, which brings the history through the generations to the present day.

An important beginning to the history of electronic music is the ability to record sounds, which was not possible until 1867. It was then that Leon Scott deMartinville first recorded sound outlines onto cylinders coated with carbon (lampblack). This important discovery was the precursor to the phonograph. Just a decade later, in 1878, Thomas A. Edison patented the phonograph, which uses cylinders as demonstrated first in deMartinville's device. Although cylinders continued to be used long after this, it was soon after the phonograph came into use that Emile Berliner developed the phonograph disc, in 1897. Also in this year, Berliner developed the telephone transmitter. [20] 

In Copenhagen in 1898, Valdemar Poulsen patented the first magnetic recording machine, which used wire as the recording medium. This device was named the "Telegraphone." It caused a sensation in 1900 when it was exhibited at the Exposition Universelle in Paris. Over the next couple of decades, many experimental devices were invented, some of which became obscure as the technology surpassed them. One such device was an instrument called the Telharmonium, which was created by Thaddeus Cahill in 1902. The Telharmonium was also known as the Dynamaphone, and was able to produce any combination of notes and overtones, at any dynamic level. This instrument was a predecessor of the famous RCA Synthesizer later installed at CPEMC in the 1950s. The major drawback of the Telharmonium was that it weighed over two hundred tons and was large. It soon fell into obscurity. [21] 

A significant invention, which was later to have a profound effect on electronic music, was Lee DeForest's triode "audion" — this was the first vacuum tube. Invented in 1906, this ultimately led to the amplification of electrical signals, electronic computation, and other endless electronic feats. Just a year later, another significant contribution was made to the advent of experimental music. This was the 1907 publication of Ferruccio Busoni's Sketch for a New Aesthetic of Music, which discussed the use of electrical and other new sound sources in future music. He wrote of the future of music: "Only after a long and careful series of experiments, and a continued training of the ear, can render this unfamiliar material approachable and plastic for the coming generation, and for Art." [22]  Also in the Sketch for a New Aesthetic of Music, Busoni states:

"Music as art, our so-called occidental music, is hardly four hundred years old; its state is one of development, perhaps the very first stage of a development beyond present conception. And we talk of 'classics' and 'hallowed traditions'! And we have talked of them for a long time!

"We have formulated rules, stated principles, laid down laws — we apply laws made for maturity to a child that knows nothing of responsibility! This child-music-it floats on air! It touches not the earth with its feet. It knows no law of gravitation. It is well nigh incorporeal. Its material is transparent. It is sonorous air. It is almost Nature herself. It is free!

"But freedom is something that mankind has never wholly comprehended, never realized to the full. Man can neither recognize nor acknowledge it. He disavows the mission of this child; he hangs weights upon it. This buoyant creature must walk decently, like anyone else. It may scarcely be allowed to leap — when it were its joy to follow the line of the rainbow, and to break sunbeams with the clouds!" [23] 

Through this writing, as well as his personal contact, Busoni was to have a profound effect on many musicians and composers, perhaps most notably his pupil, Edgard Varese. Varese said of his experience:

"Together we used to discuss what direction the music of the future would, or rather, should take and could not take as long as the straitjacket of the tempered system. He deplored that his own keyboard instrument had conditioned our ears to accept only an infinitesimal part of the infinite gradations of sounds in nature. He was very much interested in the electrical instruments we began to hear about, and I remember particularly one he had read of called the Dynamophone. All through his writings one finds over and over again predictions about the music of the future which have since come true. In fact, there is hardly a development that he did not foresee, as for instance in this extraordinary prophecy: 'I almost think that in the new great music, machines will also be necessary and will be assigned a share in it. Perhaps industry, too, will bring forth her share in the artistic ascent.'" [24] 

In Italy, the Futurists were coming at the changing aesthetic from a different angle, but one that also affected the world of classical music. A major thrust of the Futurist philosophy was to value "noise," and to place artistic and expressive value on sounds that had previously not been considered even remotely musical. A quote from their manifesto states that their credo is: "To present the musical soul of the masses, of the great factories, of the railways, of the transatlantic inters, of the battleships, of the automobiles and airplanes. To add to the great central themes of the musical poem the domain of the machine and the victorious kingdom of Electricity." [25]  In 1914, futurist Luigi Russolo held the first "art-of-noises" concert in Milan on April 21. This used his "Intonarumori", described by Russcol as "acoustical noise-instruments, whose sounds (howls, roars, shuffles, gurgles, etc.) were hand-activated and projected by horns and megaphones." [26]  In June, similar concerts are held in Paris.

Another development, which aroused the interest of many composers, occurred in 1919–1920. In Leningrad, Leon Theremin (actually Lev Termen) built and demonstrated his "Etherophone", which was later renamed the Theremin. This led to the first compositions for electronic instruments, as opposed to noisemakers and re-purposed machines. Composers who ultimately utilized the Theremin included Varèse (in his piece Ecuatorial (1934)), Stokowski, and others. In 1929, Joseph Schillinger composed First Airphonic Suite for Theremin and Orchestra, premiered with the Cleveland Orchestra with Leon Theremin as soloist.

The 1920s have been called the apex of the Mechanical Age and the dawning of the Electrical Age. In 1922, in Paris, Darius Milhaud began experiments with "vocal transformation by phonograph speed change." [27]  These continued over the next 5 years (to 1927). This decade brought a wealth of early electronic instruments — along with the Theremin, there is the presentation of the Ondes Martenot, which was designed to reproduce the microtonal sounds found in Hindu music, and the Trautonium. Maurice Martenot invented the Ondes Martenot in 1928, and soon demonstrated it in Paris. Composers using the instrument ultimately include Messiaen, Jolivet, Honegger, Milhaud, Varese, and Koechlin. In 1937, Messiaen wrote Fets des bells eaux for 6 ondes-martinot, and featured the instrument as a soloist in Trois petites liturgies de la Presence Divine. The Trautonium was also invented in 1928, and in 1940, Richard Strauss used Trautonium in his Japanese Festival Music. This new class of instruments, which are microtonal by nature, was adopted by composers slowly at first, but by the early 1930s there is clearly a burst of new works incorporating these and other electronic instruments.

In 1924, Ottorino Respighi composed The Pines of Rome, which calls for the use of a phonograph recording of nightingales. This probably constitutes the first true "electroacoustic" composition/performance; that is, the first combination of acoustic instruments with an electronic device. However, this is actually more along the lines of using of a sound effect, as was occurring in radio or film at the time, and therefore should probably not really be considered a proper electroacoustic composition. The following year, Antheil first composed for mechanical devices, electrical noisemakers, motors and amplifiers in his unfinished opera, Mr. Bloom, as a response to the "art of noises" of Russolo, Marrinetti and the other Futurists. And just one year later in 1926, was the premiere of Antheil's Ballet Mechanique, using car horns, airplane propellers, saws and anvils.

Recording of sounds made a leap in 1927, when American inventor J. A. O'Neill developed a recording device that used magnetically coated ribbon. Surprisingly, however, this failed to take off commercially. Two years later, Laurens Hammond established his company for the manufacture of electronic instruments. He went on to produce the Hammond Organ, which was based on the principals of the Telharmonium, along with other developments including early reverberation units. [28]  In that same year, A. Givelet and P. Coupleux develop an instrument utilizing oscillators controlled by punched paper rolls. This is arguably the first real "synthesizer". Just a few years later (in 1935), another significant development was made in Germany. Allgemeine Elektrizitäts Gesellschaft (AEG) demonstrated the first commercially produced magnetic tape recorder, called the "Magnetophon". The tape itself was invented by Fritz Pfleumer, and manufactured by I.G. Farben AG. Audio tape, which had the advantage of being fairly light as well as having good audio fidelity, ultimately replaced the bulkier wire recorders.

In 1939, John Cage composed Imaginary Landscape no.1 while teaching at The Cornish School in Seattle. The piece calls for muted piano, cymbal, and two variable-speed turntables playing records of test tones. This could be considered the first use of electronically produced sounds as instrumental voices. This differs from Antheil's use of mechanical gadgets, and from Respighi's use of recordings as pure sound effect (bird sounds). Cage composed two more pieces in his Imaginary Landscape series, both in 1942 while in Chicago, which expanded on this pioneering work. He composed March (Imaginary Landscape no. 2) for percussion quintet and amplified coil of wire, and then Imaginary Landscape no. 3 for percussion, tin cans, muted gong, audio frequency oscillators, variable speed turntables, frequency recordings (test tones), buzzer, amplified coil of wire, and marimba amplified with a contact microphone.

The post-war 1940s were a time of much activity, both in Europe (particularly France and Germany), and the United States. In Paris, Paul Boisselet was experimenting with disc and tape procedures. Ultimately, composers in France favored recording and manipulating acoustic sounds, and are the progenitors of Musique Concrete. In the United States, the focus turned more toward the generation of sounds, as well as the generation of compositions through use of computers. In 1946, the ENIAC (the Electronic Numerical Integrator and Computer) was invented, the first true computer.

In 1948, Radiodiffusion-television Francaise (RTF) broadcast composer Pierre Schaeffer's Etude aux Chemin de Fer on October 5th. This was the first "movement" of Cinq etudes de bruits, and marked the beginning of studio realizations and musique concrete. Schaeffer employed a disk-cutting lathe, four turntables, a four-channel mixer, filters, an echo chamber, and a mobile recording unit. Just a year later, in 1949, Schaeffer created a musique concrete piece using flute sounds as the raw material: Variations sur une Flûte Mexicaine (Variations on a Mexican Flute). This piece marked the first use of flute in conjunction with electronics. The piece was broadcast on Paris Radio on November 3. In late January of 1950, it was played at a tape concert at the Paris Conservatory. Not long after this, Pierre Henry began collaborating with Schaeffer, a collaboration that was to have profound and lasting affects on the progression of electronic music. Also associated with Schaeffer, Varese begins work on Déserts for chamber orchestra and tape. The tape parts were created at Pierre Schaeffer's studio, and were later revised at Columbia University.

In 1950, Schaeffer gives the first public (non-broadcast) concert of musique concrete at the Ecole Normale de Musique in Paris. "Schaeffer used a PA system, several turntables, and mixers. The performance did not go well as creating live montages with turntables had never been done before." [29]  Pierre Henry later that same year collaborated with Schaeffer on Symphonie pour un homme seul (1950) the first major work of musique concrete. In Paris in 1951, in what was to become an important worldwide trend, RTF established the first studio for the production of electronic music. Also in 1951, Schaeffer and Henry produced an opera, Orpheus, for concrete sounds and voices.

Meanwhile, back in the United States, sounds were being created electronically and used in composition, as exemplified in a piece by Morton Feldman called Marginal Intersection. This piece is scored for winds, brass, percussion, strings, 2 oscillators, and sound effects of riveting, and is one of those that uses Feldman's "box notation" system. Feldman composed this at the age of twenty-five. The Music for Magnetic Tape Project was then formed by John Cage, Earle Brown, Christian Wolff, David Tudor, and Morton Feldman, and lasted three years until 1954. Cage completed Williams Mix while working with the Music for Magnetic Tape Project.The group had no permanent facility, and had to rely on borrowed time in commercial sound studios.

Also in the U.S., in the same year, significant developments were happening in New York City. Columbia University purchased its first tape recorder — a professional Ampex machine — for the purpose of recording concerts. Vladimir Ussachevsky, who was on the music faculty of Columbia University, was placed in charge of the device, and almost immediately began experimenting with it. Russcol writes: "Soon he was intrigued with the new sonorities he could achieve by recording musical instruments and then superimposing them on one another." [30]  Ussachevsky said later: "I suddenly realized that the tape recorder could be treated as an instrument of sound transformation." [31] 

On May 9 of that year, Ussachevsky presented several demonstrations of tape music/effects that he created at his Composers Forum, in the McMillin Theatre at Columbia University. In an interview, he stated: "...I presented a few examples of my discovery in a public concert in New York together with other compositions I had written for conventional instruments." [32]  Otto Luening, who had attended this concert, remarked: "The equipment at his disposal consisted of an Ampex tape recorder...and a simple box-like device designed by the brilliant young engineer, Peter Mauzey, to create feedback, a form of mechanical reverberation. Other equipment was borrowed or purchased with personal funds." [33] 

Just three months later, in August of 1951, Ussachevsky traveled to Bennington, Vermont at Leuning's invitation to present his experiments. There, the two collaborated on various pieces. Leuning described the event: "Equipped with earphones and a flute, I began developing my first tape-recorder composition. Both of us were fluent improvisors and the medium fired our imaginations." [34]  They played some early pieces informally at a party, where "a number of composers almost solemnly congratulated us saying, 'This is it' ('it' meaning the music of the future)." [35]  Word quickly reached New York City. Oliver Daniel telephoned and invited the pair to "produce a group of short compositions for the October concert sponsored by the American Composers Alliance and Broadcast Music, Inc., under the direction of Leopold Stokowski at the Museum of Modern Art in New York. After some hesitation, we agreed... Henry Cowell placed his home and studio in Woodstock, New York, at our disposal. With the borrowed equipment in the back of Ussachevsky's car, we left Bennington for Woodstock and stayed two weeks. ...In late September, 1952, the travelling laboratory reached Ussachevsky's living room in New York, where we eventually completed the compositions." [36] 

Two months later, on October 28, Vladimir Ussachevsky and Otto Luening presented the first Tape Music concert in the United States. The concert included Luening's Fantasy in Space (1952) — "an impressionistic virtuoso piece" [37] using manipulated recordings of flute — and Low Speed (1952), an "exotic composition that took the flute far below its natural range." [38]  Both pieces were created at the home of Henry Cowell in Woodstock, NY. After several concerts caused a sensation in New York City, Ussachevsky and Luening were invited onto a live broadcast of NBC's Today Show to do an interview demonstration — the first televised electroacoustic performance. Luening described the event: "I improvised some [flute] sequences for the tape recorder. Ussachevsky then and there put them through electronic transformations." [39] 

These short few months were some of the most exciting in music history and technology, and the profundity of it was recognized at the time. It seems doubtful that electroacoustic music ever received such a wide audience again, unless one includes televised concerts by latter day rock and jazz fusion groups. Others were certainly active exploring new technology also. In that same year, 1951, former jazz composer Raymond Scott invented the first sequencer, which consisted of hundred of switches controlling stepping relays, timing solenoids, tone circuits and 16 individual oscillators.

After this point, we see a spate of compositions utilizing the new technology, and a great deal included acoustic as well as electronic sounds. In 1952, Henk Badings composed the Capriccio for violin and two sound tracks, which is one of the earliest known pieces for combined electric and acoustic sounds. That same year, the first piece to use flute as an acoustic instrument along with electronics was composed. This was done by Bruno Maderna, and was entitled Musica su Due Dimensioni (Music in Two Dimensions) for flute, percussion, and electronic sounds on tape. The tape part was later revised in 1958. The following year, Luciano Berio composed his Mimusique n. 1, and Luening and Ussachevsky collaborated again, this time composing Rhapsodic Variations for orchestra and tape. Edgard Varese, in France, received an Ampex tape recorder as an anonymous gift and began work on Déserts, for orchestra and tape, while Stockhausen, in Cologne, completes Studie I.

An important new development was the advent of computers for the purpose of composing music, as opposed to manipulating or creating sounds. Iannis Xenakis began what is called "musique stochastique," or "stochastic music," which is a method of composing that employs computers and mathematical probability systems. Different probability algorithms were used to create a piece under a set of parameters. Xenakis used a computer to aid in calculating the velocity trajectories of glissandi for his orchestral composition Metastasis.

1954 saw the advent of what would now be considered authentic electric plus acoustic compositions — acoustic instrumentation augmented/accompanied by recordings of manipulated and/or electronically generated sound. Three major works were premiered that year: Varese's Déserts, for chamber ensemble and tape sounds, and two works by Leuning and Ussachevsky: Rhapsodic Variations for the Louisville Symphonyand A Poem in Cycles and Bells, both for orchestra and tape. By dint of his beginning work on Déserts the year before, in 1953, the prize for being the first to compose a "proper" electroacoustic piece should probably go to Varese. Because he had been working at Schaeffer's studio, the tape part contains much more concrete sounds than electronic. "A group made up of wind instruments, percussion and piano alternates with mutated sounds of factory noises and ship sirens and motors, coming from two loudspeakers." [40]  Déserts was premiered in Paris in the first stereo broadcast on French Radio. At the German premiere, which was conducted by Bruno Maderna, the tape controls were operated by Karlheinz Stockhausen. [41]  The title Déserts, suggested to Varese not only, "all physical deserts (of sand, sea, snow, of outer space, of empty streets), but also the deserts in the mind of man; not only those stripped aspects of nature that suggest bareness, aloofness, timelessness, but also that remote inner space no telescope can reach, where man is alone, a world of mystery and essential loneliness." [42]  Meanwhile, Stockhausen composed his Elektronische Studie II — the first electronic piece to be notated.

In 1955, more experimental and electronic studios began to appear. Notable were the creation of the Milan Studio de Fonologia RAI, (with Luciano Berio as artistic director), a studio in Tokyo founded by Mayazumi, and the Phillips studio at Eindhoven, Holland, which was later shifted to University of Utrecht Institute of Sonology in 1960.

The impact of computers continued in 1956. Lejaren Hiller and Leonard Isaacson composed Iliac Suite for string quartet, the first complete work of computer-assisted composition using algorithmic composition. "... Hiller postulated that a computer could be taught the rules of a particular style and then called on to compose accordingly." [43]  That same year Stockhausen composed Gesang der Jungelinge, the first major work of the Cologne studio, based on text from the Book of Daniel. An important technological development of that year was the invention of the Clavivox synthesizer by Raymond Scott with subassembly by Robert Moog. Later, Milton Babbit began applying serial techniques to electronic music.

"From 1950 to 1960 the vocabulary of tape music shifted from the fairly pure experimental works which characterized the classic Paris and Cologne schools to more complex and expressive works which explored a wide range of compositional styles. More and more works began to appear by the mid-1950's which addressed the concept of combining taped sounds with live instruments and voices. There was also a tentative interest, and a few attempts, at incorporating taped electronic sounds into theatrical works." [44] 

1957 saw an exciting new development in computer technology. The first use of a computer to generate sound was demonstrated at Bell Telephone Laboratories, New Jersey by Max Mathews, whoused the MUSIC4 program running on an IBM mainframe computer, which used a primitive digital to analog converter. Mathews later left Bell Labs to work at Stanford, which became a major center for electronic and computer music. In 1958, University of Illinois at Champaign/Urbana established the Studio for Experimental Music under the initial direction of Lejaren Hiller. The studio became, and remains, one of the most important centers for electronic music research in the United States.

The public remained interested in the new sounds being created around the world, as can be deduced by the inclusion of Varese' Poeme Electronique, which was played over four hundred loudspeakers at the Phillips Pavilion of the 1958 Brussels World Fair. That same year, Mauricio Kagel, an Argentinean composer, composed Transicion II, the first piece to call for live tape recorder as part of performance. The work was realized in Cologne. Two musicians performed on a piano, one in the traditional manner, the other playing on the strings and wood. Two other performers used tape to unite the presentation of live sounds with the future of pre-recorded materials from later on and its past of recordings made earlier in the performance.

In 1959, one of the most important and influential studios was formed. The Columbia-Princeton Electronic Music Center (CPEMC) was formed by Vladimir Ussachevsky and Otto Luening of Columbia, and Milton Babbitt and Roger Sessions in Princeton with the help of a $175,000 Rockefeller Grant. Other composers involved included Mario Davidovsky, Luciano Berio, Milton Babbitt, Charles Wuorinen, Smiley, and Jacob Druckman. In 1960, CPEMC obtains a RCA Mark II synthesizer, the first major voltage-controlled synthesizer. This is the same year that the integrated circuit was invented.

By this time, a strong community of composers and musicians working with new sounds and instruments was well established, and growing. 1960 witnessed the composition of Luening's Gargoyles for violin and tape as well as the premiere of Stockhausen's Kontakte for electronic sounds, piano, and percussion. This piece existed in two versions — one for 4-channel tape, and the other for tape with human performers. "In Kontakte, Stockhausen abandoned traditional musical form based on linear development and dramatic climax. This new approach, which he termed 'moment form,' resembles the 'cinematic splice' techniques in early twentieth century film." [45] 

The 1960s also saw the development of large mainframe computer synthesis. Max Mathews of Bell Labs perfected MUSIC V, a direct digital synthesis language. Concurrent with this was the development of smaller voltage-controlled synthesizers by Moog and others that made instruments available to most composers, universities and popular musicians. A well-known example of the use of these synthesizers is the Switched-on Bach album by then Walter (now Wendy) Carlos. This time is also the true beginning of live electronic performance. The Synket, a live performance instrument used extensively by composer John Eaton in works such as Concert Piece for Synket and Orchestra (1967), was invented. ONCE Festivals, featuring multimedia theater music, were organized by Robert Ashley and Gordon Mumma in Ann Arbor, MI. Milton Babbit composed his first electronic work using the synthesizer — his Composition for Synthesizer — which he created using the RCA synthesizer at CPEMC. "For Babbitt, the RCA synthesizer was a dream come true for three reasons. First, the ability to pinpoint and control every musical element precisely. Second, the time needed to realize his elaborate serial structures were brought within practical reach. Third, the question was no longer "What are the limits of the human performer?" but rather "What are the limits of human hearing?" [46] 

The collaborations also occurred across oceans and continents. In 1961, Ussachevsky invited Varese to the Columbia-Princeton Studio (CPEMC). Upon arrival, Varese embarked upon a revision of Déserts. He was assisted by Mario Davidovsky and Bulent Arel. [47]  The intense activity occurring at CPEMC and elsewhere inspired the establishment of the San Francisco Tape Music Center in 1963. It was established by Morton Subotnik, and soon incorporated a voltage-controlled synthesizer based around automated sequencing by Donald Buchla, and used in album-length Subotnik pieces such as Silver Apples of the Moon (1967) and The Wild Bull (1968).

Back across the Atlantic, in Czechoslovakia, 1964, the First Seminar of Electronic Music was held at the Radio Broadcast Station in Plzen. Four government-sanctioned electroacoustic music studios were later established in the 1960s under the auspices of extant radio and television stations.

New instruments continued to develop. In 1964, the first fully-developed Moog synthesizer was completed. Robert Moog began public sales the following year (1965). Another popular instrument was the Hammond organ. In 1965, Karlheinz Stockhausen composed Mikrophonie II for choir, Hammond organ, electronics and tape. In 1966, the Beach Boys became the first pop music group to use electronic instruments (using a variation on the Theremin, in the song "I Just Wasn't Made for These Times" on Pet Sounds). The Beatles follow a year later by using concrete techniques on Sgt. Pepper's Lonely Hearts Club Band, directly influenced by recordings of Stockhausen.

1967 was another exciting year for electronic music. Leon Kirschner composed String Quartet No. 3, the first piece with electronics to win the Pulitzer Prize. Also that year, Max Mathews and F. Richard Moore developed GROOVE, a real-time digital control system for analog synthesis, eventually to be used extensively by composers Laurie Spiegel and Emmanuel Ghent in the 1970s. In 1979, Sequential Circuits company introduced the Prophet, the first synthesizer to use microprocessor control.

In 1970, Charles Wuorinen composed Times Encomium, the first Pulitzer Prize winner for an entirely electronic composition. Also in the 1970s, the Mini-Moog was created. This was a small, integrated synthesizer that made analog synthesis easily available and affordable, along with newcomers ARP and Oberheim. This paralleled the development of real-time digital synthesis. Charles Dodge composed Speech Songs (1972) based on early speech synthesis research. Jon Appleton (with Jones and Alonso) invented the Dartmouth Digital Synthesizer, later to become the New England Digital Copt's Synclavier. Barry Vercoe wrote Music 11, a next-generation music synthesis program (later evolving into csound, which is still widely used). IRCAM (Paris) became a major center for computer music research and realization and development of the 4X computer system, featuring then revolutionary real-time digital signal processing. Pierre Boulez's Repons (1981) for 24 musicians and 6 soloists used the 4X to transform and route soloists to a loudspeaker system. "Under the general direction of Pierre Boulez and funded by the French government, IRCAM is a large and active research organization devoted to the scientific study of musical phenomena and to bringing together scientists and musicians to work on common interests." [48] 

In the mid to late 1970s, the British band Throbbing Gristle spawned an entire sub-genre dubbed industrial music. Electroacoustic music and experimental electronic music thus became a widespread musical "underground" outside of academe thanks in part to "taper culture" — a sort of western samizdat in which musicians and composers traded and distributed their works on cassette tapes (much cheaper and more accessible that vinyl). The most respected (and popular) practitioners of "industrial music" were and continue to be knowledgeable of academic composers in the oeuvre and informed by their theoretical works. These would include groups such as the Hafler Trio, Jim O'Rourke, Organum, Sonic Youth, and Illusion of Safety.

Moving into the '80s, Bob Moog announced the MIDI specification in an article in Keyboard Magazine in 1982. Just prior to the release of the DX-7, a group of musicians and music merchants met to standardize an interface by which new instruments could communicate control instructions with other instruments and the prevalent microcomputer. This standard was dubbed MIDI (musical instrument digital interface).

"This technology allows a single keystroke, control wheel motion, pedal movement, or command from a microcomputer (e.g., an Apple Macintosh) to activate every device in the studio remotely and in synchrony, with each device responding according to conditions predetermined by the composer." [49] 

In the 1980s MIDI instruments and software made powerful control of sophisticated instruments easily affordable by many studios and individuals. Acoustic sounds became reintegrated into studios via sampling and sampled-ROM-based instruments. Miller Puckette developed graphic signal-processing software for 4X called MAX (after Max Mathews) and later ports it to Macintosh (with Dave Zicarelli extending it for Opcode) for real-time MIDI control, bringing algorithmic composition availability to most composers with modest computer programming background. At the same time, Sequential Circuits introduced the Prophet 600 — the first MIDI keyboard

Soon thereafter, in 1983, Yamaha introduced the first stand-alone digital synthesizer, the DX-7. It used frequency modulation synthesis (FM synthesis), first experimented with by John Chowning at Stanford during the late '60s, "turning FM synthesis from a software algorithm that ran on mainframes into chips that powered a commercial synthesizer took seven years." [50]  In 1985, the final MIDI specification was published by the MIDI Manufacturers Association. Also in 1985, Digidesign released Sound Designer software for the Macintosh, this being the first consumer-level hard disk recording and editing software. David Jaffe, Julius Smith and Perry Cook (CCRMA studios of Stanford University) prototype physical modeling, a method of synthesis in which physical properties of existing instruments are represented as computer algorithms which can then be manipulated and extended.

Barry Vercoe describes one of his experiences with early computer sounds:

"At IRCAM in Paris in 1982, flutist Larry Beauregard had connected his flute to DiGiugno's 4X audio processor, enabling real-time pitch-following. On Guggenheim at the time, I extended this concept to real-time score-following with automatic synchronized accompaniment, and over the next two years Larry and I gave numerous demonstrations of the computer as a Chamber musician, playing Handel flute sonatas, Boulez's Sonatine for flute and piano and by 1984 my own Synapse II for flute and computer the first piece ever composed expressly for such a setup. A major challenge was finding the right software constructs to support highly sensitive and responsive accompaniment. All of this was pre-MIDI, but the results were impressive even though heavy doses of tempo rubato would continually surprise my Synthetic Performer. In 1985 we solved the tempo rubato problem by incorporating learning from rehearsals (each time you played this way the machine would get better). We were also now tracking violin, since our brilliant young flutist had contracted a fatal cancer. Moreover, this version used a new standard called MIDI, and here I was ably assisted by former student Miller Puckette, whose initial concepts for this task he later expanded into a program called MAX." [51] 

The last decade brought a flurry of new activity. In the 1990s, interactive computer-assisted performance started to become popular. A description of a new real-time development follows:

"Automated Harmonization of Melody in Real Time: An interactive computer system, developed in collaboration with flutist/composer Pedro Eustache, for realtime melodic analysis and harmonic accompaniment. Based on a novel scheme of harmonization devised by Eustache, the software analyzes the tonal melodic function of incoming notes, and instantaneously performs an orchestrated harmonization of the melody. The software was originally designed for performance by Eustache on Yamaha WX7 wind controller, and was used in his composition 'Tetelestai', premiered in Irvine, CA in March 1999." [52] 

Tod Machover (MIT and IRCAM) composed Begin Again Again for "hypercello," an interactive system of sensors measuring physical movements of the cellist. This piece was premiered by Yo-Yo Ma. Max Mathews perfected Radio Baton to compliment his Conductor program for real-time tempo, dynamic and timbre control of a pre-input electronic score. Morton Subotnik released a multimedia CD-ROM All My Hummingbirds Have Alibis. Many used MIDI technology to compose works that included acoustic instruments (such as James Mobberley's Caution to the Winds for piano and tape) pioneered by Mario Davidovsky's Synchronisms series several decades earlier.