Like politics and organised crime, the world of popular music is one in which the most influential figures often operate beneath the surface, beyond the gaze of the general public. These are music's Alastair Campbells, plotting from secret rooms and clandestine recording studios, at the rear of whatever's new and important, elbowing it forward, but simultaneously way out in front.
Todd Rundgren is the king of these behind-the-scenes sorcerers. His CV for the years 1969 to 1980 reads like a shadow history of pop according to Zelig: the amount of cataclysmic activity seems hard to attribute to an ordinary, sleep-dependent human-being. Within weeks of quitting his hard-rocking Anglophile band, The Nazz, a twenty-two-year-old Rundgren was predating David Bowie's androgynous alien sex-fiend image by two years with what Esquire magazine called "the best wardrobe in rock 'n' roll". By 1973, he'd completed his fourth solo album, revolutionised the use of the synthesizer, written his own triple-length Pet Sounds, twiddled the knobs on the album which many argue gave birth to punk (The New York Dolls' eponymous debut LP), and formed a prog-rock group on the side (the frequently-ridiculed Utopia).
"I would plaster my working hours with music," he recalls. "That's all I did. I made music. I also made it in a hurry. There just seemed to be so many possibilities. Why dwell on any of them?"
By day, he was one of the world's best-paid producers. By night, he made home-brewed, technologically advanced double albums. "I'd listen to each record until I was sick of it, until I could find its weakest element. Some people would look at it as egotism, but I was so afraid of looking back in 10 years and thinking: 'God, did I do that?'" It was his own foolproof way of reinventing himself, ensuring that he never stood still.
If you're not in the mood for one Todd Rundgren, another, more appealing one is never far away: the hyperactive wizard; the lounge geek, the power-pop pin-up; the twiddler; the blue-eyed balladeer. On Something / Anything?, the 1972 double album which reached number eight in our recent Alternative Best Albums Ever poll, you get the best bits of all five, and what The Rough Guide To Rock accurately describes as "one of the greatest distillations of popular music ever recorded". Like the Rolling Stones' Exile On Main St, it is one of those rare albums where not just the songs, but the context of their creation, comes through - there's a special sense of being "let in".
Something/Anything? was Rundgren's biggest-selling album, but, after going through the arduous playback procedure, he started to see the songs as formulaic. "I was writing about relationships out of habit, relationships that had ended years ago," he remembers. He began to experiment with the drug Retalin, appeared on live TV dressed as a man-eating peacock and made A Wizard, A True Star, his chaotic, multi-layered "stream of consciousness" album. "From that point on, it was me exploring me, rather than the music. Each record became a snapshot of my own development."
Pigeonholing Rundgren went from difficult to downright impossible. If he was a futuristic computer wiz-kid, how come he dealt in old-fashioned counterculture ideals? If he was a prog-rocker, how come he hung around with Patti Smith and produced The New York Dolls? If he was a technophile, how come he recorded at home?
Does he ever feel overwhelmed, looking back at his split personalities? "I think other people feel more overwhelmed by it. But it was never the result of schizophrenia; more of an evolution, really. These days I feel more overwhelmed by taking care of my family in a world that's constantly changing - that's the reason I don't do three double-albums in two years any more."
The vast, chameleon-like nature of Rundgren's music dictates that many of his fans are obsessives: Rundgren's scrambled psyche is a thing that takes a special kind of devotion to absorb. In 1980, when Mark Chapman was picked up by the NYPD after shooting John Lennon, he was wearing a promotional T-shirt advertising Rundgren's 1978 album The Hermit Of Mink Hollow. It has been suggested that Chapman had decided to take a much-hyped war of words between Lennon and Rundgren out of the letters pages of the music press and into his own hands.
"Because I'm so interested in exploring the nature of consciousness, it didn't strike me as that peculiar," says a defiantly un-spooked Todd. "I mean, taking your obsession to the point of assassination is a little much, but I'd been obsessed with meeting The Beatles too; I just didn't want to do it with a gun in my hand."
Does he regret the dispute with Lennon? "No. At that time, he'd gone from being this trailblazer to a phase of pure, derivative, imitative self-indulgence. All that Elvis crap. I was questioning his status as a revolutionary. He'd been talking about changing the world, and now he was just going out and abusing waitresses and making a complete asshole of himself."
If Rundgren seems un-fazed by pop's most notorious killer, it's because he's always been interested in the symbiotic relationship between fan and star. He's been known to collect autographs from the crowd at his gigs, and the inner sleeve of 1974's Todd album contained a portrait of Rundgren constructed entirely from fans' names. Ever the futurist, he now distributes his music exclusively via the Internet, allowing subscribers to his TR-1 website to hear songs in various stages of completion.
"There's a certain insiderism and tyranny to the way record labels and radio stations are run," he laments, "and that's why the Internet looks so appealing. I think the new catchphrase for the music industry has got to be service, not product. It's become too ingrained with this idea that music is about a disc, and further and further away from the idea of performance. Let's get fan loyalty back. Let's give people freedom of choice. Let's make all the music available on a server and develop a system that tracks how often it gets listened to."
Electronic innovator, influential sonic architect, natural precursor to Prince's glam wildcat, computer-age wizard - Todd Rundgren is still out there, ahead of the game. If any man's lectures on the future of music are worth paying attention to, his certainly are.
• Todd Rundgren's first five albums are re-realeased this week on Castle. A greatest hits album, Go Ahead. Ignore Me, is also out on Castle
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