From composing sountracks for films such as Magnolia and Eternal Sunshine of the Spotless Mind to producing albums for the likes of Kanye West and Fiona Apple, Jon Brion is the hippest backroom wizard around. Jim Carroll meets him in New York.

JON BRION'S back-pages are starry ones. Besides a clutch of quirky soundtracks for such films as Punch-Drunk Love, Eternal Sunshine of the Spotless Mind and Magnolia, you'll find Brion's name attached to all manner of albums as producer or songwriter. Aimee Mann, Fiona Apple and, most recently, Kanye West may be the marquee names, but Brion has also worked with Brad Mehldau, Rufus Wainwright, Badly Drawn Boy and a concert hall of others. If you want your music to benefit from a sumptuous, theatrical orchestral pop sound, there's really only one fellow to call.

Tonight, though, Brion simply wants to be a song-and-dance man. At New York's Canal Rooms, his live set weaves a wayward way through covers (paying his respects to David Bowie, Prince and The Yeah Yeah Yeahs, amongst others), soundtrack out-takes and songs penned or co-penned by Brion himself. It's a hugely entertaining and engaging affair as it veers hither and thither across the musical universe.

Brion has been doing a similar show at the Largo club in Los Angeles every Friday night for the last eight or nine years, with regular guest appearances from the likes of Michael Stipe and Elvis Costello. There's a strong sense that these live outings are as much Brion's way of letting off steam after another long week in the studio as an opportunity to try out new tunes and ideas.

"As long as people keep showing up and paying attention, I will keep doing the shows," he says. "I've chosen to do something where both my work and my life are integrated and both are happening simultaneous every hour I'm awake."

While it may be his tag as soundtrack composer of choice which is largely responsible for pulling in the crowds, Brion's musical roots extend far beyond the big screen. Growing up in New Jersey with a father who directed concert bands and a mother who sang in jazz groups, music was destined to be Brion's calling.

A move to Boston in 1987 was a big step in this regard. There, he played solo gigs, formed a band called World's Fair and toured with Aimee Mann's Til Tuesday. When the calls from Los Angeles started to come, offering him studio gigs, he decided to relocate there.

Even as Brion formed The Grays with ex-Jellyfish guitarist Jason Falkner, he found himself more and more in demand on the other side of the studio. Throughout the 1990s, Brion seemed to be permanently behind the mixing desk, building an enviable reputation for his work and compiling a stellar client list.

"Any work you get is because people have heard other work you've done," he says. "And the only reason they hire you is they want to co-opt some of what you do, because they think it'll make what they do better. And I mean that about everything that I do, like doing sessions, doing a movie soundtrack, producing a record or co-writing a song."

He likes to make sure acts know what they're getting when they hire him. "I'm not in any way anti-success for myself or the people I'm associated with, but I'm not going to make musical decisions based on what's going to make people more commercially successful. I see this every day in the studio and it's just a drag to be around. Those people who just want to have a homogenous record and who want to make sure it's the current, chart-like thing around can go somewhere else."

He says he's now at the stage where he can pick and choose the projects he wants to work on: "The people I'm attracted to are already smart and trying to figure out how to communicate with people. They want to make something different. If I think they're good, if I think they have something to offer, if I think they're individuals, then I'm interested in doing something with them."

This seems especially true of film directors. "The kind of people who approach me don't want the standard soundtrack to begin with, so working with Paul Anderson or Michel Gondry or Charlie Kaufman is a pleasure. Even the hard parts of the work are a pleasure because you are involved in something good. It's very easy to collaborate with people who are talented because even if it's tough, you're happy to defer to them."

When it comes to scoring films, Brion's method differs sharply from his peers. "The average film composer who works all the time is so tired of dealing with the politics that they have their own home studios that they work in and they don't want people coming by. In general, I'm sitting with the directors and we're watching the films together and I'm composing while we're sitting there. If I was working with somebody and I didn't actually like their movie, I'd have such a horrible time."

There have been times when Brion has thrown caution to the winds and done the unexpected. His hook-up with Kanye West for the Chicago rapper/producer's Late Registration album is one such instance.

West, a fan of Fiona Apple's music and the soundtrack to Eternal Sunshine, arranged to meet Brion through über-producer Rick Rubin. The pair clicked and they put the bones of Gold Digger together on their first afternoon in the studio.

Brion says the project was an eye-opener. "I mean, I'd never made a hip-hop record in my life before, but it was completely apparent that Kanye was open to investigating new ideas. When he hears something he likes, he knows it and he makes quick, intuitive decisions. I'd watch him take a rough track that I had worked on and completely stand it on its head in 10 minutes - mind-boggling stuff."

For Brion, the goal when he starts producing is the same as it ever was: to make music to remember.

"What stays in my head are those records I've loved throughout my life. You get a record you love and it's the record you play for a whole era of your life. You know there will be four or five months of your life where you listen to it almost every day. I've had so many records like that, and that's the thing I try to remember when I'm making records.

"I want to make something that feels like a complete world, so you can live in it."