With so many visitors it's sometimes hard to know who's the star and who's the guest, hip-hop has perfected the art of the cameo.

But with the exception of Santana's multi-platinum Supernatural and recent CDs from Stevie Nicks and Sheryl Crow, most rock artists have been less willing to share their albums with a raft of guest vocalists and players.

A pair of upcoming albums from two punk/new wave legends, though, takes the idea of star-studded collabos and twists them around in two unexpected ways.

The solo debut from Violent Femmes lead singer Gordon Gano, Hitting the Ground (August 27), is so star-studded that the nasally voiced singer could only squeeze his vocals onto three of the 11 tracks.

Of course, it helps when your songs are sung by the likes of two different members of the Velvet Underground (Lou Reed and John Cale), PJ Harvey frontwoman Polly Jean Harvey, former Pixies singer Frank Black, They Might Be Giants, and ex-4 Non Blondes singer and Pink/Christina Aguilera producer Linda Perry.

On the flip side, John Doe, singer for Los Angeles punk legends X and leader of the John Doe Thing, simply called some of his friends in to help out on his upcoming fourth full-length solo album, Dim Stars, Bright Sky (August 20). His friends just happen to be folks like Jakob Dylan, Aimee Mann, Juliana Hatfield and Go-Go's member Jane Wiedlin, whose contributions are decidedly more subtle than Gano's collaborations.

"I thought, 'Wouldn't it be cool to sing with them ... people who I respect as people and artists?' " Doe said of his first acoustic album, which he tagged as "folk soul." "I have a difficult time separating the two, because if I don't like the person I usually don't like what they sing about."

Gano came by his high rollin' cameos through a back door. His first solo effort after 20 years fronting the Femmes was conceived as the soundtrack to a film by David Moore ("Polish Spaghetti"). The indie filmmaker tapped Gano for the project after seeing a performance of the "Blister in the Sun" singer's musical, "Carmen: The First Two Chapters" at New York's avant-garde Knitting Factory club.

"It started because I thought that, for a movie, it seemed silly if the same voice is singing in the background all the time," Gano said. While, like Doe, Gano nabbed some friends to voice his songs, he'd never met some of the guests, such as Perry.

"I was vaguely familiar with her, but there were probably only five or 10 seconds of the 4 Non Blondes record that had something that I liked vocally," he said candidly. The two bonded on the phone, though, over their mutual love of smoky jazz singer Nina Simone, and Perry turned in a nuanced, sensual vocal that surprised both her and Gano.

In another surprise, Polly Jean Harvey's take on the title track features her amazing, quavering imitation of Gano's signature vocal style over a driving folk punk track, which he took as a high compliment.

Though Gano wrote all of the songs and recorded rough demos for his colleagues (and in some cases finished songs awaiting their vocals) to work off of, only punk godfather Lou Reed got a co-songwriting credit.

"I told him about the project and he said if he had time and was inspired that he would try to do something," Gano said of his musical hero. "Well, at the point where I thought it wasn't going to happen, he called and said he was done, but that he'd changed some of the lyrics." As it turned out, in addition to rewriting more than half of the lyrics to the playful sung/spoken "Catch 'Em in the Act," Reed also completely rearranged the song's phrasing in a way that Gano said he could have never imagined.

Being the old-school punk that he is, Doe had always eyed all-star albums with a healthy dose of skepticism. But, after years of being asked why he hadn't recorded an all-acoustic album, Doe finally decided that the songs he'd been writing seemed to call for a more mellow setting, so he swallowed his punk rock pride and unplugged.

Bringing along his friends for the ride suddenly didn't seem like such a bad idea, either.

"The same part of me that resisted doing an acoustic album resists being pigeonholed and worries about getting old, or soft," Doe said. "It's difficult to maintain that intensity after you've relied on electric guitars and fast tempos. Making rock music is very seductive and you always wonder, 'I've been at 10, am I getting to 10 this way?' "

While he traded bashing drums, electric guitars and loud vocals for pedal steel, mandolin, acoustic guitars and piano, Doe found a different kind of intensity. Paired with female singers who complement his voice in a more seductively poppy way than the edgier vocals of his longtime partner in X, Exene Cervenka, Doe's voice takes on a mellower, wounded tone on the album. Songs like "Closet of Dreams," "Still You" and "Backroom" are a series of elliptical poems about lives hanging in the balance and fuzzy portraits of characters barely keeping hold of the ones they love, and in some cases, themselves.

With a solo career that has frequently drawn more accolades than record sales, Doe said he thought the novelty of an acoustic album, paired with the guests, couldn't hurt his prospects.

"I'd be a liar if I said I did it strictly because of the art," he said. "Eighty percent of the people that say 'I love John Doe' have no idea what I sound like. But I also realize that it's cool and people like those things in an age where there's so many things going on at once and every small advantage my help you make another record."

Similarly, Gano said he wasn't concerned that his voice doesn't appear all over his solo debut, because his guests wont' likely hurt sales, either. "It was just very natural in how it developed," he said. "Maybe it's like my version of a hip-hop solo record!"