THE story lines of “The O.C.” may be getting tawdry, but its music is as edgy as ever – giving unknown bands valuable airtime.

” ‘The O.C.’ has given us the chance to reach millions,” says Alex Greenwald, the frontman of Phantom Power, who sing the show’s title track, “California.” “The people behind ‘The O.C.’ know the audience would like to be turned on to new music.”

The show has featured tunes by Johnathan Rice, Stars and Franz Ferdinand – bands usually reserved for college radio. And last week, the Beastie Boys chose “The O.C.” to debut “Ch-Check It Out” from their upcoming album.

“Radio remains so bizarre and unreliable as an outlet for music that any other outlet is welcome,” says Matthew Caws of Nada Surf, who covered “If You Leave” for a recent episode.

“We like the show. And it seems like the guy [executive producer Josh Schwartz] goes by his own taste.

And it makes a difference: After indie band Rooney performed on the show, their album sales spiked by 30,000 copies.