The main reason why Brian Eno has reached 60 without having been tackled by a biographer is that it's hard to get him all in focus. As David Sheppard points out early on in this honourable, authorised attempt to do justice to a mind-bogglingly restless and prolific subject, “writing about Eno can sometimes feel like folding down a skyscraper into a suitcase”.

Unlike most successful rock musicians, who tend to devote their later careers to cashing in on their earlier successes, Eno has spent the 35 years since he gave up playing synthesiser for Roxy Music in a ferment of experimental activity and theoretical blurting. Many of his musical moves have received plenty of attention. He is renowned as the inventor of a genre he named “ambient” (electronically textured background music) and he has been championed by U2, the most famous of the many acts whose albums he has produced. “We didn't go to art school, like so many bands, we went to Brian,” Bono memorably commented. Coldplay are the latest rock giants to have hired Eno to sprinkle some arty fairy dust on their studio work.

But music is only one string in his curious bow. For the past 20 years, Eno has pursued a parallel career as an exhibiting artist, specialising in luminous installations that deploy unusual light sources such as televisions. His other interests range from perfume (he has lectured on the topic, as well as creating his own) to a recently discovered passion for party politics: he is an eloquent supporter of the Lib- Dems and their anti-war stance.

And this is only the stuff he chooses to make public. Much of what Eno gets up to, such as the male-voice choir he leads every week in his London studio, and the horticultural experiments he conducts in the garden of his Oxfordshire manor house, are done mainly for his own amusement. Not that he is ever, apparently, motivated by much else.

One of the interesting revelations in Sheppard's book, disclosed by Eno's long-term wife, Anthea Norman-Taylor, is that he chooses never to know how much he is being paid for any job commission on the grounds that it might influence the amount of time and attention he pays to it. Sheppard aptly compares Eno to a man in his garden shed “sporadically emerging to show the world what he's been building in there”.

For those more interested in the man than his multifarious projects, the most surprising discovery here, given his cerebral image, will probably be Eno's fascination with sex. This supplied his early inspiration. The son of a postman father and a Catholic Belgian mother, Eno grew up in rural Suffolk, reading Pears Encyclopedia and National Geographic, which he would scour for photographs of unclothed tribeswomen. Convinced that he was “terribly ugly” and that he would “never be able to get girls”, he adopted a stratagem that was to serve him well in his career. “I began cultivating certain eccentricities, figuring that perhaps then girls would like me.”

About the most eccentric thing a teenage boy could do in a sleepy East Anglian town like Woodbridge in the early 1960s was to play in a pop group. Unaccomplished on any instrument, he began messing around with a reel-to-reel tape recorder. Eno's talent for attention-grabbing stunts was honed at Ipswich art school, where he was taught by Roy Ascott, an avant-garde theoretician with little interest in traditional methods. Having already initiated a young guitarist called Pete Townshend into the ideas of Gustav Metzger the auto-destructive German sculptor, Ascott was just the man to stoke Eno's interest in John Cage, the modernist composer famous for his arrestingly silent piece, 4 Minutes, 33 Seconds.

Inflamed by such ear-catching weirdness, Eno swiftly turned it to musical - and amorous - use. After a brief marriage and the birth of his first daughter Hannah, he left his wife and set off for psychedelic London. Here he joined Roxy Music, put on a feather boa and make-up, and proceeded to feast on the groupies who flocked to their gigs. According to his room-mate on an early Roxy tour, who remembers being kept awake most nights by the keyboard player's prolonged and noisy couplings, Eno would take Polaroid photos of his conquests and proudly lay them all out on the floor at the end of the tour. He wrote a song, The Fat Lady of Limbourg, in memory of one.

There was loads more guilt-free casual sex to be had once Eno's solo career took off. On a holiday to Thailand in 1979, he was recognised by the German owner of a girlie bar who invited him to stay for two weeks, all incidentals paid. When Eno moved to New York in 1980, he did so, he said, because “its beautiful women are at the cutting edge of culture just by the way they move, the way they look”. Among the many striking things Eno has to say about his unusual libidinous preferences, two stand out: his claim to be “terribly attracted to women with ocular damage,” and his cryptic assertion that “the bottom is the large brain”.

With his uninhibited fondness for sex and intriguing cultural hypotheses, Eno comes across in On a Faraway Beach as an archetypal man of the 1970s. This is the aspect that most engages Sheppard. A rock journalist of the Mojo magazine, history-first school, he spends more than 350 pages telling the story up until 1981 (lingering over the Roxy era, and Eno's working relationship with David Bowie and Talking Heads) then dispatches the next 27 years in 100 pages, relegating Eno's lengthy sabbatical in St Petersburg in 1994 to a couple of paragraphs.

Sheppard is not uncritical of Eno's airy theorising, quoting various friends who echo Roxy's manager David Enthoven's view that “Eno is the best second-hand car salesman I've ever met. He could sell you anything.” But it's the quirkily plausible public figure that preoccupies the author to the point where he has little to say about Eno's private life in middle age, the complicated marriage to Anthea, and their two teenage daughters. Then again, as Sheppard argues, Eno probably deserves an ‘Eno-cyclopedia Britannica,' all to himself. In that case, much of this book would serve nicely as the first volume.

On Some Faraway Beach by David Sheppard
Orion £20 pp451 Buy from Books First £18.00 with free delivery

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