When I was asked to do this, it was an immediate and enthusiastic yes. From early on I've been a big fan of Joanna's. It's great music and great storytelling with an amazing sense of narrative. She has such a compelling voice; it's what you notice first. It's so singular, so much her own.

One of the things about great artists is that they don't sound like anybody else. Elvis sounds like Elvis; Joanna sounds like Joanna. Even though that's the first thing someone would notice, now it's the last thing I notice. I'm interested in noticing where the melody falls. I'm interested in learning these songs.

You do hear people describe her in terms of this medieval Renaissance folk music, but it's not that so much as it's just somebody who's got something important to say. She's worked it out in a way that's very personal, and because of that and because of the construction of her songs—which are sizable; they're real statements—it's fun and it's brilliant. The players in the orchestra are really going to have a wonderful time.

The orchestra itself is unusual—if you were to visit the players' MySpace pages you'd see their influences ranging from Fado to Slayer. Because the orchestra is hand-picked and has been playing together on all these great projects—Brokeback Mountain, Eternal Sunshine, really fantastic movie scores—when they come together for a project like this, it comes together really quickly. And of course we've all heard [Ys] and it's spectacular.

This is not driven [like a typical rock orchestra project]. I believe this was driven first of all by Joanna's interest in [composer] Van Dyke Parks. That's why the music turned out like it did. There's a history of large symphony orchestras and rock bands that goes way back—like Eric Clapton at Royal Albert Hall. This has nothing to do with that.

David Sabee will conduct the chamber orchestra accompanying Joanna Newsom's performance.