THEIR VOICES wind around the notes, sinuous and close. Kasey Chambers and Shane Nicholson aren't blood, but your ear tells you they're definitely tribe. Like Emmylou Harris and Gram Parsons, like the members of the phenomenon that was Fleetwood Mac, their voices were made to move together. And in the annals of duets between lovers, they're assured a place with their new album, Rattlin' Bones, a rare collaboration between two Australian alt-country stars who happen to be hitched.

It's a down-home, introspective effort, undertaken not long after the birth of their son Arlo, now 2. "It was a good time to take a break, be parents and a married couple," says Nicholson, adding that the usual pattern of recording and touring periodically "engulfs" their lives. The instrumentation on the collection--banjo, dobro, lap steel, acoustic guitar, fiddle--is spare and brooding, vintage Americana. But Nicholson says the breakneck eight-day recording session was actually some of the most fun he's ever had in the studio. "It's contradictory, because a lot of the record is quite dark," he says, "but it was a blast, quite fun. Some of the people in the band were some of our oldest, closest friends."

It was also one of the least production-oriented sessions of his career. "It was almost like anti-production. We were trying to strip it back, make it very old-time. The priority was always just the feeling behind the performances."

That's right up Chambers' alley. Having performed with her father and brother for years before striking out on a solo career, she says the stage has become a place for her that's all about community. "I actually find when I'm onstage it's as much about being around people as the music," she says. "I love telling stories and talking about my family and my kids and--telling stories that have nothing to do with music! I like it to feel like you're in my laundry [room], sitting around at home."

The collaboration has also given Chambers the chance to do something else she used to do with the old family band: harmonize. As a solo artist with a great career--some call her the Gillian Welch of Australia--she's vocally a leading lady. With Nicholson she gets to sing alto and tenor while he takes the lead, and likewise take the lead when it's his turn to harmonize. Nicholson says it's just become second nature. "We don't rehearse or anything," he says. "It's gotten to a point where we kind of understand how each other sings, and it's become very natural for us to be playing together."

KASEY CHAMBERS and SHANE NICHOLSON play Thursday, Aug. 20, at 7:30pm at the Rio Theatre, 1205 Soquel Ave., Santa Cruz. Tickets are $25 at www.snazzyproductions.com or 831.479.9421.

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