Electricity, you might have noticed, is all the rage, and all music today, to a greater or lesser extent, is electronic. That performance you heard last night at Wigmore Hall of Schubert’s C major String Quintet likely built on a relationship with the piece that began on disc, where recording engineers had made conscious decisions about where to place microphones. That pop song rippling discreetly in the background of a chain cafe as you settle down with your copy of Gramophone to read this article reminds you of how the sound of popular music was utterly changed by the emergence of the electric guitar in the mid-1950s; gone was the neat acoustic balance of crooner against big band as in came a carefully staged mix of electric guitars, electric bass and drums. Electricity changed our experience of music and the German philosopher Walter Benjamin, in his 1936 essay The Work of Art in the Age of Mechanical Reproduction, worried that, because of recording, art was now in danger of prostituting its authentic soul; ‘its presence in time and space, its unique existence at the place where it happens to be’ was under threat.

But what of electronic music that aimed to go further than merely messing with our perception of music as it already existed? This article is concerned with a deeper definition of electronic music – electronics pulsating through the imaginations of Edgard Varèse, John Cage, Karlheinz Stockhausen and Pierre Henry, composers whose desire to invent a whole new vocabulary of sound changed indelibly the relationship between composers and their material, audiences and music, music and recording. Unexpected allegiances emerge. Only one degree of separation takes you from Ferruccio Busoni to Frank Zappa; the John Cage and Cornelius Cardew- inspired British electronic music composer Brian Eno uses his ideas of electronically transformed sound to embed abstract soundscapes inside Bowie’s 1977 pop classic Heroes; Richard Skelton, a composer in his forties who has immersed himself in the fell lands of Northern England, deploys the latest digital technology to capture dark visions of landscape, rebooting a tradition that stretches back to Birtwistle and Vaughan Williams. Meanwhile electronic composers like Klara Lewis, Robert Curgenven, Valerio Tricoli, Francisco López and the anonymous enigma that is Eleh continue to create music that ingeniously redefines concepts of harmony and structure.

For a long while, electronic music existed only as an inkling about what could be achieved rather than presentations of actually realised music. The works now canonised as the first electronic classics – Cage’s Imaginary Landscape No 1, Pierre Henry and Pierre Schaeffer’s Symphonie pour un homme seul, Varèse’s Déserts and Poème électronique and Stockhausen’s Gesang der Jünglinge – would emerge during the 1940s and ’50s, the way prepared by decades’ worth of speculative theory and imaginative fantasy.

Ferruccio Busoni’s book, Sketch of a New Aesthetic of Music, was published in 1907, as Mahler was working on his mighty Eighth Symphony and Schoenberg was beginning to piece together his tonality-busting Second String Quartet, and reveals its author to be music’s all-seeing, all prophesying Nostradamus. Before Schoenberg had committed his first fully-fledged atonal notes to manuscript paper, Busoni was already dismissing as a false dichotomy the hot-headed debate that would ensue between tonal hardliners and atonal militants. To use atonality as a critique of tonality was to miss the point entirely, he asserted. Harmony had become a slave to equal temperament, his argument continued, and could only be refreshed by subdividing the octave into third- (not semi-) tones, which raised immediate questions about the ubiquitous status of conventional instruments and music notation. Such instruments were ‘fettered by a hundred limitations’, and Busoni proposed that new technologies were required to override limitations of tuning, timbre and range. ‘I think in the great new music, machines will be necessary’, he wrote. ‘The full flowering of music at present is frustrated by our instruments.’

Varèse met Busoni when he relocated to Berlin in 1906. In his previous life in Paris, he had studied (with decidedly mixed results) with D’Indy, Roussel, Widor and Massenet, and befriended Debussy, who would prove supportive, but nobody quite stirred his imagination like Busoni. When, in 1966, Varèse published an article he called The Liberation of Sound, which collated statements made over the previous 30 years, the tone remained unmistakably Busoni-esque. Talk of liberation from ‘the arbitrary paralysing tempered system’ was straight out of Busoni’s Sketch; and Varèse also pressed the importance of using electronic means to subdivide the octave into ‘the formation of any desired scale’ and conjure into being dynamics, cross-rhythms and extreme registers of low and high which were ‘far beyond the present human-powered orchestra’. He was also interested in ‘a sense of sound projection in space by the emission of sound in any part or in many parts of the hall as may be required by the score’, and of lines related in mathematical proportions too intricate for human performers to count. For all the potency of his ideas, Busoni’s music remained defiantly old-school. But Varèse turned concept into sound – and perhaps the value of Busoni’s ideas were precisely that they remained theoretical, handing Varèse raw data upon which he could work.

Listening to Varèse’s Poème électronique some 60 years after its unveiling – inside the Philips Pavilion designed by the Modernist architect Le Corbusier at the 1958 Brussels World’s Fair, alongside electronic music by Iannis Xenakis – you become aware of how skilfully Varèse distilled a lifetime of thought about electronic music inside a compressed, disciplined eight-minute structure. On CD one essential is lost; Varèse engineered the piece for a network of speakers that bounced sound around the building, transforming his musical structure into sound that actively journeyed around the space. Rumbling undercurrents of percussion and piano put you in mind of his pioneering 1931 percussion ensemble piece Ionisation; but Varèse devises a context that has nothing to do with the expectations of the concert hall, or of the natural grain of how acoustic instruments breathe, attack or sustain. In the studio Varèse used technology to dive inside objets trouvés; the sound of an aircraft taking off, and of human voices, had their melodic contours stretched and kneaded into other shapes and temperaments. Sounds are brutally cut. Brief silences allow the music to inhale. Blasts of pure electronic sine waves – the most basic electronic humming vibration – puncture the surface. Elaborate overlays of multiple sound sources overwhelm the senses. More hectic silence. Then a single piercing yelp escapes from the sound mass – a gesture that undresses the music, revealing its naked essence.

The sadness surrounding Poème électronique is that Varèse was already 75 when the invitation came to create the piece. Alongside the wedges of collaged tape music inserted inside his 1954 orchestral piece Déserts, this would be the only electronic music Varèse completed. Speculating around what might have been achieved had he been handed earlier opportunities proves an irresistible tease, although his legacy inserts itself in unlikely places: Frank Zappa’s 1966 debut album Freak Out! contains a tribute to Varèse, then wraps up its loose ends with a raucous, chopped-up, overlaid collage of borrowed recorded music against everyday sounds. A whole 17 years earlier than Poème électronique – in 1941 – John Cage wrote to Varèse, praising a recent article about electronic music. ‘I hope your work is established in some laboratory. It certainly should be’, he wrote. ‘The general lack of audacity, desire to explore, on the part of heads of companies having laboratories is increasingly un-understandable.’

Cage’s letter was part of a campaign to raise funds for the foundation of a centre of experimental music – and of electronic music in particular – in the United States. ‘Only through the use of electrical means’, Cage reasoned, ‘may important advances in the exploration of sound be made’; and later, ‘American music will be enlivened and enriched by such exploration and use of new musical materials. These can best be brought about through the cooperation of scientists with a real appreciation of music, and composers with an understanding and appreciation of science’.

The idealism Cage espouses – the notion that an alliance of composers and scientists would liberate music from stuffy classical orthodoxies and herald a brave new world of music – is a recurring trope throughout the evolution of electronic music. An interview I did with Karlheinz Stockhausen in 2000 elicited this intriguing thought about what electronics bring to the party that acoustic instruments can’t: ‘I have always tried to look for music behind the acoustic environment that we live in – the real music is often hidden behind the surface of life.’ These words resonated in sympathy with sentiments expressed in my 2009 interview with another trailblazer of electronic music, French composer and musique concrète pioneer Pierre Henry. The title of Henry’s 1997 composition Intérieur/Extérieur became the focus of our discussion, as Henry explained that the ‘intérieur’ of a sound can only be revealed by recording its ‘extérieur’, then using the studio to freeze-frame or slow sound down to the point where a composer can reach inside and rearrange its harmonic particles.

The music of Cage, Stockhausen and Henry represents three radically different mid-20th-century ways of perceiving electronic music, but each composer agreed about the need to define a distinct poetic sensibility, fantasy world even, around this emerging aesthetic. The generosity of vision that had led Busoni towards his Sketch of a New Aesthetic of Music would soon be hijacked by the less benevolent Filippo Tommaso Marinetti, whose 1909 Manifesto of Futurism spoke of sounds of the future – but also rehearsed ideas of de-humanisation that would reappear in The Fascist Manifesto he co-authored in 1914, with Europe tipping towards catastrophe. Cage’s letters show a painful awareness of those earlier connotations, while Stockhausen and Henry, who both experienced wartime Europe first-hand, acted to reclaim electronics as a fresh point of departure.

Stockhausen’s Gesang der Jünglinge (1955-56) remains one of the great humane statements of post-war music, the piece you play to anyone who peddles untruths about all Modernism being cold, clinical and obsessed only with its own materials. Words from the Book of Daniel, sung by a young boy, are dispersed across five separate speakers and, as Stockhausen breaks the words down into single syllables and phonemes, or builds the voice into a lusty choral mass, the music begins to feel joyous and ecstatic. The message is clear: in the Book of Daniel, Nebuchadnezzar throws three Jews into a fiery furnace from which they emerge unharmed and intoning praise to God. Stockhausen uses electronics to heighten that idea; the technology might be new-fashioned, but the celebration of the human voice, and all it could symbolise in post-war Europe, is deeply rooted and fundamental.

Gesang der Jünglinge is regularly cited as electronic music’s first masterwork, but Symphonie pour un homme seul (‘Symphony for a Man Alone’) by Pierre Henry, working in collaboration with the electronic music theorist Pierre Schaeffer, was completed in 1950 and demonstrated that whimsy could also be part of the electronic arsenal. The piece has an absurdist, playful quality that puts you in mind of Jacques Tati or the French mime tradition. We visit this ‘Man Alone’ in a sequence of vignettes, each telling us about a particular mood or emotional state. Immediately a divergence of technical approach opens up between Stockhausen and Henry. Stockhausen takes a single source, analyses it, and filters it into a spectrum of tones from which to compose. Henry’s music is interested in the discontinuity of many different sound sources, recordings of doors slamming, trains hurtling through tunnels and speech patterns creating a jagged web of association. His music also raises the prospect that the slam of a door can, musically, enjoy the same status as an immaculately executed line on a cello: ‘To make music I have to make a game out of it’, he told me. ‘I don’t “play” music, more like I play with my sounds and it’s exhilarating because this world of sound dances inside me.’

Henry struck a note of regret as he complained that the emergence of digital technology, of computers and sampling, handed composers preset sounds whereas, back in the day, his music lived or died by the quality of the sounds for which he searched. Is this critique fair? After the war, the establishment of electronic music studios in Cologne, Paris, Milan and New York scratched the itch for fresh discovery, but objections are often voiced that electronic music squandered its edge when it was sucked into academic institutions at an accelerating rate during the 1960s. But when the American composer Morton Subotnick released his album Silver Apples of the Moon in 1968, it was a moment of reckoning. Gone were tape splices and expensive studio time. Subotnick’s music was typical of music conceived on a synthesiser which offered instant access to electronic sound via the touch of a keyboard.

As synthesiser technology developed, electronic music became democratised, versatile and portable. Eighty years after Walter Benjamin expressed his concerns that recording robbed music of its presence in time and space, technology has developed in ways he could never have imagined. Richard Skelton – obsessively stalking the moors, recording his own instrumental improvisations which are mixed with sounds of the environment, and then crafted into imposing structures – plays absorbing games with time, place and space. His transformation of natural sounds heightens their natural curvature and weather-beaten grandeur; they become more than sonic postcards of the place ‘it happens to be’. The emotional interior of these exterior sounds is revealed in some of the most beautiful music being created today.

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