A pair of captivating folk/pop troubadours -- one firmly established on America's playlists, the other just now gathering a flock -- delighted a less-than-capacity crowd at the Robert Mondavi Summer Music Festival Saturday night with an evening of mellow, yet provocative musicmaking.

Grammy Award-winning Shawn Colvin shared enduring works of craft and catharsis as program headliner, while a winsome youngster half her age, Washington's Brandi Carlile, engaged listeners with solid songwriting and musicianship.

Definitely unplugged, the two acoustic sets also gave the rapt crowd an opportunity to hear not only familiar songs but also new material to be included on upcoming recordings. Colvin's is due out in early September, Carlile is due in the studio next week to lay down a dozen tracks.

An intense live performer, Colvin impresses the viewer as a musician born with a guitar in her hand. In addition, her songwriting is a perfect match for her guitar talents.

Colvin was born in Vermillion, S.D., and by the age of 10 had developed considerable passion for music. A self-taught guitarist, she formed a hard rock band as a teenager in Carbondale, Ill., but abandoned that avenue when the group's high-energy demands strained her voice. In the late '70s, she moved to Austin, Texas -- the city she now calls home -- singing with a Western swing band until nodes forced a temporary retirement at age 24. In 1983, she moved to New York, where she found a home in the city's singer/songwriter scene, and built a following in New York and Boston through constant gigs. Through the '80s she worked her way up the folk circuit, also appearing in Off-Broadway shows such as "Pump Boys and Dinettes" and "Lie of the Mind." She got her first break in 1987 singing backup on Suzanne Vega's hit, "Luka."

A devout Joni Mitchell disciple in her teenage years, Colvin shifted from a decided country sound after meeting multi-instrumentalist John Leventhal who collaborated on the artist's award-winning debut recording, "Steady On," in 1989.

Colvin's breakthrough came with another Leventhal collaboration, "A Few Small Repairs." From it came a suite of narrative songs and portraits, the most celebrated of which, "Sunny Came Home" -- the story of a frustrated housewife who torches her own home -- gave Colvin a Top 10 hit and two of Grammy's biggest honors, Record of the Year and Song of the Year.

She did take a break from recording and touring for a few years to raise a daughter, Caledonia, who accompanied her mother to the Mondavi concert Saturday.

Although Colvin's voice is not real strong, it has a warmth and a certain huskiness that is quite appealing. From a refreshing acoustic arrangement of Donovan's "Catch The Wind," which opened her 85-minute set, to a touching closer, Barry Gibb's "Words," Colvin proved to be a first-rate entertainer.

With self-deprecating humor -- she poked fun at everything from songwriting focus ("my theme is always death and regret") to her own attire (a bubble skirt worn over white pants, topped off by a couture copy of the perennial wife-beater) -- and a treasure trove of old and new songs, the headliner gave slightly less than 800 fans -- including vintner Robert Mondavi -- something to cheer about.

An admitted teetotaler at this point in her life, Colvin told her host and audience "everything I learned about wine is from (the film) 'Sideways.' No merlot, right?"

After satisfying fans with the popular "You and the Mona Lisa" from her Grammy Award-winning '97 CD, Colvin served up a few songs from the recording due out in September. She said her slice-of-life dramas will continue her theme of "bummeresque overviews," performing "These Four Walls" (enduring or escaping?) and "What I Like," an autobiographical work that contains a few four-letter words. "My daughter wants to charge me a dollar every time I sing it," Colvin quipped.

She responded to requests, including "Trouble" for a birthday celebrant and the dreamy "Wichita Skyline" to a plaintive call from the darkness. The bittersweet piece of introspection, "Polaroids," was heartbreakingly honest, as was a brand new tune that struck a responsive chord, "(Give Me Sam Cooke Singing) Don't Worry Me Now."

Talent to spare

With country-tinged, bell-clear voice and an obvious talent to condense her observations of the passing scene into meaningful song, 24-year-old Brandi Carlile is a performer whose melancholy balladeering belies a sunny disposition.

Labeled a female Roy Orbison, Carlile is a back-to-nature sort who lives in an isolated cabin outside Seattle with a dog, cat, horse and acoustic guitar. Growing up in isolated foothills of Washington, Carlile turned to music for company and taught herself to sing. "I locked myself in my room when no one was at home to see how loud and high I could sing," she confessed. She figured out how to play the piano ("I wanted to be like Elton John") and eventually guitar at 17.

Her determination and work ethic paid off two years ago when she signed with Columbia Records to record her first compact disc. It's a showcase for her expressive voice -- several songs from it were featured in her 35-minute opening set -- which can alternate from bluesy growl to aching falsetto, even within the same composition.

Carlile's material addresses everything from love found to love lost, as well as a new song ("that Patsy Cline would have written if she had more tattoos") expressing the relief one feels fleeing a sour relationship, "I'm Over You." It was so heartfelt that I suspected it might have been an autobiographical lament. She also fared well with a rousing rendition of Johnny Cash's "Folsom Prison Blues" and Leonard Cohen's ambiguous "Hallelujah," which deals with the dynamic of a relationship by using spiritual metaphor.

Saturday's double bill gave us an opportunity to enjoy two talented songwriters and performers on a stripped-down stage devoid of today's usual electronica. The ladies lived up to their advance billing. What a show!

The concert series continues Aug. 12 with the smooth jazz of guitarist Norman Brown, vocalist Patti Austin, saxophonist Paul Taylor and pianist Alex Bugnon. For tickets, call 1-888-769-5299 or log online at www.robertmondaviwinery.com