STRING THEORY.

The cover of Joanna Newsom's new album, "Ys," is an oil painting by the California artist Benjamin Vierling. Newsom is depicted with plaited blond hair, wearing a billowing blouse and a garland of flowers. She is seated at a window on a thronelike chair, holding a sickle in her right hand and a tiny gilt-framed painting of a moth in her left. A blackbird perches on the windowsill, a cherry in its beak; beyond lie valleys and hills. A press release issued by Newsom's record label, Drag City, says that Vierling "did the cover painting old-master style, with layers of egg-tempera and glazes. Strictly 16th-century processes, just like the recording of the album."

The Renaissance references may be a joke, but a careful, almost precious husbandry of the past is characteristic of Newsom's work. Newsom, who is twenty-four, is a classically trained harpist, and "Ys"--pronounced "eess"; it's the name of an island in Breton mythology--is a series of complex, through-composed songs that have more in common with Kurt Weill's long-form ballads than with contemporary pop music. Yet Newsom tends to perform in rock clubs, not concert halls, and many of her fans--including the novelist Dave Eggers, who praised her "bare and unflinching" music in Spin--are devotees of independent rock. Moreover, the songs on "Ys" feature lush, intricate orchestral arrangements by the pop composer Van Dyke Parks. (Parks, who was a child actor, worked on Rufus Wainwright's 1998 debut record and on "Smile," the legendary album by the Beach Boys, which was begun in 1967 but not completed until 2004.)

Newsom is sometimes lumped with a group of acoustic musicians called "freak folk" or "free folk." They include the bands Tower Recordings and Feathers and the warbling singer and songwriter Devendra Banhart, with whom Newsom shares a fearlessness and a deceptively childlike air. In essence, however, folk describes simple songs that are universally accessible and performed on cheap instruments, if any. (Rap easily qualifies as folk music.) Newsom uses antique words that many English speakers won't recognize, and plays an expensive and heavy instrument that you couldn't bring on a camping trip, and some of her recent songs are almost as long as American sitcoms (average length: twenty-two minutes, without commercials).

In 2002, Will Oldham, an eccentric singer and songwriter known as Bonnie Prince Billy, heard recordings that Newsom had made herself, and brought her on tour. In 2003, Drag City released Newsom's first full-length album, "The Milk-Eyed Mender": twelve songs about "funny things," each one peppered with words like "grammerie" and "poetaster." It is odd and wonderful music, as cheerful and melodically sure-footed as it is affected and fey. Newsom plays the harp with the utilitarian clarity of a piano player in a band, vigorously plucking bass notes with her left hand while exploring chords in the upper register with her right. (Mercifully, she avoids the cascading glissandi that in movies signal "childhood memory" or "medication taking hold.") Her voice is an acquired taste: a wobbly mezzo-soprano that leaps into falsetto and breaks in a woody squeak. At first, she sounded to me like Lucille Ball reciting Edmund Spenser. She brought to mind a college student I knew who wore suspenders to show that she would not countenance this debased modern world.