HOLLYWOOD — Dave Navarro sits on a throne during "Rock Star: Supernova," CBS' summer school of Reality Rock, entertaining those in "American Idol" withdrawal on Tuesdays and Wednesdays through September.

Directing the interactions between the show's contestants and the hard-rock supergroup they're vying to front, he's as relaxed on network TV as a half-clothed man with multiple piercings and tattoos could possibly be.

He apparently feels just as secure off camera: The show shares a soundstage with "Idol," and Navarro recently mentioned on his blog that he's been using Simon Cowell's temporarily vacant dressing room as his own.

On recent "Rock Star" episodes, Navarro, who co-hosts with model Brooke Burke, is hitting a balance of sarcasm and seriousness that's turning him into the Cowell of the heavy-metal set. It's an unlikely fate for a musician who played a key role in the West Coast underground scene that challenged rock norms in the 1980s, and led to the invention of rock's "alternative" style.

Navarro's early role in helping re-imagine rock glamour as guitarist for Jane's Addiction and, briefly, the Red Hot Chili Peppers, is more than a decade past. But this exotic creature's ability to establish himself at the center of the rock universe raises interesting questions about what makes a rock star these days and how the mainstream and the underground have merged.

"Rock Star" is just one of Navarro's projects. The guitarist has been on an upward arc since 2000, when he cleaned up nasty heroin and cocaine habits and traded membership in a single band for frantic multitasking. Now, on the verge of launching The Panic Channel, a new group with ex-Jane's Addiction members Stephen Perkins and Chris Chaney and singer-songwriter Steve Isaacs, Navarro's living more like a mogul than a guitar-slinging road rat.

The past half-decade has seen Navarro venture into every likely pop field except acting and (this one has to be coming) fashion design. He published "Don't Try This at Home," a disturbingly frank account of his drug struggles, co-written with Neil Strauss. He's played "Jingle Bells" Hendrix-style in a Gap ad. He's partnered with artists as disparate as Christina Aguilera, Jay Z, Michael Jackson and his "Supernova" buddy Tommy Lee. His all-star cover band, Camp Freddy, still draws a crowd and plenty of famous guest vocalists after five years.

On those few nights he spends at home, Navarro hosts an Internet radio broadcast, Spread Radio Live, linked to 6767.com, his friendly, smart and frequently updated blog.

And most famously, his (currently dissolving) marriage to fellow pop star-of-all-trades Carmen Electra was chronicled in the cuddly 2003 MTV reality show " 'Til Death Do Us Part," which showed America that a guy who wears fishnet shirts and digs porn can write his own vows and cry when saying them, helped him cultivate the accessible aura he projects on "Rock Star."

His all-around success speaks volumes about the current rock zeitgeist.

When he first gained national fame with Jane's Addiction in the late 1980s, he was a shaggy-haired half-goth, half-hippie kid whose style bridged Led Zeppelin and The Cure. As Jane's Addiction developed, so did Navarro — his guitar playing getting more adventurous, his personal style blossoming as he became a symbol of Modern Primitive sexiness.

In the 1990s, Navarro's path paralleled that of alternative rock, whose amorphousness made it a gateway for anything considered too weird for the mainstream. His brief stint in the Chili Peppers typified his midcareer persona: "One Hot Minute," the only Chili Peppers album upon which Navarro appears, marked a new sense of exploration for the band, featuring a dreamier, more pensive sound.

Although the album did well on the charts, however, many thought it a dangerous detour — and that wariness was fed by the video for the single "Warped," in which Navarro and singer Anthony Kiedis shared a soul kiss that some fans found unsettling. He ultimately couldn't fit into this quintessentially frat-boy band and left because of "artistic differences" and his worsening drug habit. He sank into rock's background.

During Navarro's dark period, "alternative rock" also headed into crisis. Kurt Cobain was several years dead and other bands that had shifted the mainstream began to fall into disarray. Hip-hop became the new source of "weird" ideas for the mainstream.

As rock moved from the center of the pop cosmos to a more balanced position as one of many galaxies, a new kind of rock star was needed — one who wouldn't cling too heavily to any one set of artistic or even moral preferences, instead embodying a flexibility that suited the new, multi-platform musical marketplace.

This rock star would need to display a strong personal style and sense of integrity — rock still being the territory where people act out their fantasies of nonconformity and rebellion — but he'd have to be cool with sharing, across musical genres and theoretical divides.

That's Navarro, now. A clean-living fitness nut who appreciates a lap dance but likes it even better when he can share it with his wife (or so we believed until a few weeks ago, when the two "best friends" split), he has turned the rock lifestyle into something sustainable and surprisingly healthy.

Next to his fellow "Supernova" judges, he's the sexiest, with the most open-minded attitude. Tommy Lee is old-school, a panting puppy with a good heart but not a lot of savvy. Guitarist Gilby Clarke seems like the nice married dad that he is, while bassist Jason Newsted appears to be trying to engage in the therapy he avoided by quitting Metallica before the band famously hit the couch together.

Navarro, by comparison, comes off like a made-for-TV golden god: funny, reasoned, jovially lascivious toward the women and paternally tough on the men — this is still rock, after all, and mostly a man's world — but ultimately in control of his wagging tongue. Navarro has principles, fairly standard ones: be original, show passion, let go and get wild.