Singer-songwriters Jack and White perform Saturday at Harlow's

The pop-folk duo Jack and White captures the harmonies, laid-back vibe and conflicted lyrics that characterized 1970s Los Angeles rock.

You'd never know Jack Matranga and Brooke White came from elsewhere (he's a recent transplant from Sacramento, she moved from Mesa, Ariz., several years ago) and were born in the '80s.

"I am a child of the '70s, born in the wrong decade," White, 28, said by phone from her home near Los Angeles.

White, performing with Matranga on Saturday night at Harlow's, was a finalist on Season 7 of "American Idol." Her lovely, slightly gritty vocals and unadorned folk style established her as one of the most distinctive, memorable talents in show history.

Influenced by Carole King, Joni Mitchell, Carly Simon, Fleetwood Mac and other 1960s and '70s ladies and fellows of Laurel Canyon, White was mostly a solo act until she met fellow singer-songwriter Matranga, 26, formerly of the popular Sacramento band Self Against City, early last year.

Like so many musical marriages, it started with a blind date. Matranga had recently moved to L.A. to establish a new base for his songwriting and "wasn't saying no to anything," he said during a conference call with White. A mutual friend set up a songwriting session with White.

"We wrote a song before I even left her place," Matranga said.

The goal had been a song for a White solo album, but "we decided to make a duo of it," White said. "We started throwing around ideas, no big deal, not serious, let's just do it. That turned into several more songs and snowballed into something."

The duo released an EP last summer called "Gemini" and a second EP, "Winter," last month.

Self Against City was emo pop, but Matranga had grown up listening to '60s and '70s harmonies. In White, he found a collaborator who liked "the same music, and the same chord progressions," and recognized '60s and '70s Southern California rock as a great jumping-off point for Jack and White's more modern sound.

"What I like about those California bands is, beyond being incredible songwriters, they used technology and the latest equipment," Matranga said. "It was a time period where nothing was off limits as to what was a hit song."

Added White: "What you would hear on the radio was not such a narrow format (as it is now). You could have artistry and mainstream commercial quality as well."

White brings to the new act a loyal fan base from her "Idol" days.

"It was a challenge to be exposed to so many people, and hope to retain at least a fraction" of the "Idol" audience, White said. She has retained "very loyal fans – a good, solid group of people who have stuck around for the ride."

White is expecting a baby in May with her husband of eight years, Dave Ray, an accountant. ("I always call him Dave Ray, CPA," the ebullient White joked. "It's not his favorite.")

The pregnancy has not interfered with performances, White said, though she occasionally must sit down after a set. Partnering with Matranga took a load off in a more general way.

"If you find the right collaborator, it makes it a million times more fun," White said. "I (also) like being able to harmonize on the spot. It is just more of a richness of layers, musically and creatively, than when you are alone. It brings out more possibilities."

Jack and White's formation corresponded with a surge in popularity of male-female duos such as the Swell Season, She & Him and the Civil Wars. That's coincidental, Matranga said.

"There is a reason these duos are successful – there is just something really interesting about male and female (harmony)," he said. "We just happen to be doing it at a time when it kind of became prevalent again. We found out what so many other people find: that it works."

JACK AND WHITE

When: 10 p.m. Saturday; Gerald Pease opens

Where: Harlow's, 2708 J St., Sacramento

Cost: $10

Information: (916) 441-4693, www.harlows.com, www.jackandwhite.com

• Read more articles by Carla Meyer

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