Is TV the new radio? A lot of indie bands think so, thanks to the exposure they've received on one hit youth series. Jim Carroll takes a look at the OC phenomenon.

For Indie bands and underground acts, it's like winning the lottery. Your CD is sent away to an address in Hollywood, California to join hundreds of other hopefuls in boxes and sacks on an office floor. One day, a woman called Alexandra listens to your music. She nods her head and taps her feet. She likes what she hears and says to herself: "Hey, I think we could use this."

Within a couple of months, your music appears in one of those scenes on The OC where Seth and Summer are hanging out. Viewers like what they hear and begin to forage on iTunes for more of your stuff or go to their local store to pick up your CD.

The tune appears on one of the show's best-selling compilations, leading to more interest. The audience for your live show grows and you're clocking a lot of new, younger faces in the crowd who can only have heard about the band from one place.

Welcome to The OC, dude: you've become another indie rock act who can track their new-found success with a certain demographic back to the OC bounce.

For the likes of Death Cab for Cutie, Modest Mouse, The Shins, Jem, Interpol, Rooney and many others, use of their music on The OC has proven to be a turning point in their careers. Thanks to a teen TV show, bands are receiving the kind of instant exposure they just can't get from radio or touring.

From the off, OC creator Josh Schwartz wanted music - and particularly the music he liked, leftfield indie rock - to play a big part in his Beverly Hills 90210/Melrose Place-style show about beautiful people yakking about their problems in a sunny location. But even he couldn't have foreseen the impact a slot on the show would have for some of the bands featured. Certainly Death Cab for Cutie owe a lot to The OC bounce: sales of their Transatlanticism album soared in the wake of their OC slot and led to a new major label deal.

Alexandra Patsavas is the show's music supervisor. She decides who makes the cut and, as such, probably wields more power than any radio DJ. A self-confessed indie rock geek, her route to the OC began when she promoted shows by Smashing Pumpkins, Camper Van Beethoven and Jane's Addiction while studying at the University of Illinois. She cut her music-supervision teeth working with B-movie king Roger Corman and on such TV shows as Fastlane, Boston Public, Without a Trace and Roswell, before Josh Schwartz got in touch.

Patsavas is inclined to agree with the notion that TV is the new radio when it comes to breaking new bands. "I think it's because music supervisors on TV shows don't have the same constraints that radio programmers have," she says. "We can reach into catalogues or use demos or find just one song from a band that fits a specific scene.

"Because we have far less restrictions on what we use, we have a much larger pool to select from. We have the choice and the chance to spotlight music every week and be incredibly current and try a lot of things out."

Recent episodes have featured everyone from LCD Soundsystem, Chemical Brothers and Bell X1 (songs from Music in Mouth featuring in two key scenes) to Bloc Party, Juana Molina and Lou Barlow. All are artists who would never receive the same level of prime-time exposure from US radio stations.

Yet Patsavas stresses that it's the scene, not the soundtrack, that comes first. "Yes, we have really focused on what music works for the show, but it has to serve the pictures and the characters. It's about the episode as a whole and what's happening in the scene. We mix it up quite a bit. We might use Sufjan Stevens in one situation and Mark Lanegan for another."

So, there's no magic formula when it comes to selecting which tune will work?

"It's all very intangible," says Patsavas. "The song might have an interesting guitar riff or a very descriptive lyric or a great intro. We look for so many different things because so many different kinds of musical moments need to be expressed in the show. Bands from Stars and Louis XIV to Bright Eyes and Beck all find their way to The OC for different reasons."

The music on the show is a natural fit, she says, because it's "the kind of music the producers on the show listen to in their own time". Of course, as a different generation of directors and music co-ordinators start calling the shots and picking music they like, more and more indie rock can be expected on the small screen.

Record labels naturally see this as a good thing, as much for the appearance fees which their acts receive as the increased album and ticket sales as a result of the exposure. While Patsavas doesn't track how acts benefit from appearing on the show, she does point to how cooperative labels are in terms of access and clearances to their acts.

"As we've focused on music more and more, record labels and musicians have become more and more supportive and enthusiastic about what we do. If more bands on independent labels reach a larger audience because of the show, that's a good thing."

While other shows have tried to use music as a selling point (see panel), it's The OC which continues to provide the magic touch for indie rock.

Because of this, there's no end in sight to the hundreds of CDs making their way to Patsavas. She's looking out for one in particular. "I'm very much looking forward to hearing some new Snow Patrol." No doubt, that's good news for them and their label.

The OC is broadcast on TG4 on Mondays at 9pm and at various times on E4