Avril Lavigne performs during her "Best Damn Tour" concert in Singapore September 7, 2008. [Agencies]

LOS ANGELES - Get ready to hear a softer side of Avril Lavigne.

The Canadian pop singer tells Billboard.com that she's taking a more serious, stripped-down approach to her fourth studio album, tentatively slated for a November release on RCA.

"A lot of the songs are mainly the acoustic and my vocal," says Lavigne of the as-yet-untitled project. "It's a lot different from anything I've done before. It's not a pop-rock record. This is more about emotion and feeling."

Lavigne's husband (and Sum 41 frontman) Deryck Whibley produced eight of the album's projected 12 tracks, half of which she wrote by her herself. For the other half, she's been working with former bandmate Evan Taubenfield and songwriter/producer Butch Walker, who co-penned her 2004 single "My Happy Ending."

"I'm kind of just keeping it in the family with all of my close friends," says Lavigne, whose last album, 2007's "The Best Damn Thing," has sold 1.6 million copies, according to Nielsen SoundScan. "I started this record off really slow, just writing songs at home on my piano. I didn't work with a ton of people this time."

The album's first single hasn't been confirmed, but the 25-year-old Lavigne says it could "possibly" be a song that emerged from the TV commercial for her new Black Star fragrance, which will go on sale in the U.S. this fall.

"It's the first song that I recorded for this record," she says. "It's kind of like a lullaby." The ethereal, piano-driven chorus originally was written just for the ad, but Lavigne has since decided to turn it into a full recording.

Another track on the album, "Darlin,'" was written when Lavigne was 15 years old and still unsigned. "It was probably the second song I (ever) wrote; I was trying to figure it all out," she recalls. "It's really special to me."

The more mature-sounding "Everybody Hurts," meanwhile, boasts weighty guitar riffs, impressive vocals and comforting lyrics like "It's okay to be afraid." Lavigne describes the track as "different -- but not different to stray away from who I am and what I am."

Lavigne is also keeping busy these days with Abbey Dawn, a juniors clothing line that sells at Kohl's stores in the U.S. "The design process has been crazy," says Lavigne, who conceptualizes all the items in the line herself. "I just love clothes and colors and patterns. I'm very visual and very hands-on." The singer will launch the line in Canada next month and hopes to bring it to Europe and Japan.

For now, though, Lavigne's primary focus remains her music. She expects to tour North America in February, and she won't be bringing any backup dancers on the road this time. Instead, she'd like to keep the vibe of her live shows similar to that of the album.

"I want to do a cool theater tour in America because I feel it will really suit this record," she says. "I'm ready to go out there and just mellow out and sing."