Since forming in 2000, the North Carolina-based trio the Avett Brothers has been winning over audiences with roughshod live shows that dole out songs marked by ferocious strumming, string-breaking and grunge-inspired yelling alongside placid ballads and heart-on-the-sleeve lyrics. Now, with the band's upcoming major label debut I and Love and You produced by the legendary Rick Rubin--the man behind everything from the Red Hot Chili Peppers' breakthrough Blood Sugar Sex Magik to Johnny Cash's career-reviving late albums--the Avett Brothers' fans are wondering if the boys' latest step towards the mainstream will find them losing their edge.

Bassist Bob Crawford admits he's not sure whether all of the group's audience will wholeheartedly embrace the new effort, yet he sees the album as less a seismic shift in sound than the same leap forward that has occurred between past efforts. "I believe if you take [the last album] Emotionalism and this, they are not any further apart than [2004's] Mignonette and [2006's] Four Thieves Gone," he says.

I and Love and You will definitely reflect the Avett Brothers' progression as a band, though, Crawford says. "The better you get at something, the cleaner it's going to be."

At the Malibu studio where I and Love and You was recorded over a three-week period, Rubin, who won a 2008 Grammy Award for Producer of the Year, basically just suggested that the band try out tweaks in the structure of some of their songs. On some tracks, he asked the trio to try adding more of a chorus or to repeat certain instrumental passages. "He has a very mellow presence, but he's always taking notes," Crawford says of Rubin.

Apparently the famed producer was impressed that the Avett Brothers had a batch of songs before heading into the studio with him. "I think he was very intrigued with our work ethic," Crawford says. "We like to know what we are gonna do before we punch the clock."

Since recording the CD, the band has kept a tight lid on most of the new material, which is due out in August. In the past, fans were already familiar with the group's songs before the release of new albums because they'd heard them at live shows. This time around, only a handful of tracks have been debuted live. "We've done a better job of holding songs back," Crawford says.

One that has been performed by the band is "Kick Drum Heart," a piano-based pop bullet with a stuttering drumbeat on the chorus. Another is "Tin Man," an acoustic number with the band's trademark outbursts of punk energy. The band played the upcoming CD's title at this year's South by Southwest Festival and a 2008 New Year's Eve show in Charlotte, North Carolina's Belk Theater. It's a ballad with the refrain, "Brooklyn, Brooklyn, take me in/ Are you aware of the shape I'm in?" The new songs are notable for their presence of piano and drums, where most of the Avett Brothers' previous numbers involved just vocals, acoustic guitar, banjo and standup bass.

Even though the band has clearly achieved another level of notoriety--when I talked with Crawford they were opening for the Dave Matthews Band on a leg of its current tour--the bassist compares the group to the eye of a hurricane: a calm center where lots of things are changing around them. "I don't feel like we've changed at all," he says. "I know things have changed. We've made a leap from a van to a bus."

A few seconds later, though, Crawford adds one way in which the Avett Brothers are different than they were before signing to Columbia and recording I and Love and You. "I think the only way we've changed," he says, "is we've gotten better at it."

THE AVETT BROTHERS play Thursday, May 14, at 8pm at Rio Theatre, 1205 Soquel Ave., Santa Cruz. Tickets are $20, available at Streetlight Records and at www.ticketweb.com. 831.423.8209.

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