When harp player King David lost what was dear to him, he knew the value of a good cry.

But in the now-famous song that begins, "By the rivers of Babylon we sat down and wept when we remembered Zion" (Psalm 137), he hung his harp on a willow and refused to belt out the blues, even though he clearly had them.

Had she been there, modern-day harpist Sunita Staneslow might have prodded the king to go ahead and cut loose on the strings. A harp, she says, provides a "soothing, healing sound."

The St. Paul, Minn., musician — who will be in San Francisco this weekend for a concert at Congregation Beth Sholom — says the instrument's "wide range of vibrations" can ease the pain of a broken heart, or open-heart surgery, and thus "soothe the savage breast," as William Congreve wrote.

Staneslow's version of "On the Rivers of Babylon," from the CD "City of Gold — A Musical Portrait of Jerusalem," offers a summer shower to rinse away moody thoughts. Or, as Congreve added, "to soften rocks, or bend a knotted oak."

Breezy notes glide off the strings of her six-foot concert grand, coaxing soft groans from the dark cloud of a cello. A violin sighs. Tiny notes drop from bells like raindrops on drainpipe.

Abruptly, the shower's gone. Washed-out blues dry in the sun. That's when Staneslow in a live performance picks up her smaller Celtic harp and starts rocking.

"Jewish music is rich and gutsy," she says.

Trained in classical music from age 8, the Tufts University and Manhattan School of Music graduate majored in international studies, but decided to go abroad to figure out what she wanted to do with her life. "I found my niche in Israel," she says of her two-year stay.

She arrived in Jerusalem before her harp did, and washed dishes while waiting for it to clear air freight customs.

After that, she said, "So many things fell into place like magic."

She got a gig with the Jerusalem Symphony when its harpist took maternity leave for half the season.

She met and married her husband. They moved into an apartment near the Jerusalem Theater.

"We opened a cupboard and there was a picture of a girl playing a harp."

She showed the photo to her teacher, Judith Liber, who announced it was one of her own students.

"It was a harpist's apartment we were renting," she says.

When a flutist in an Israeli klezmer band needed an arranger, Staneslow slid into that role. Plus she joined a pop-rock band called Tofa'ah ("phenomenon"), which performed mainly for Orthodox women.

At first, the classically trained harpist wondered, "How could anyone religious play anything hip?" But Staneslow knew she was cranking when she saw the crowd "swaying and clapping and dancing in the aisles."

Back in the States, she founded the chamber ensemble Vida. She also teaches private students, leads workshops on such topics as "Jewish Music for Harp" and, of course, performs. Her bread-and-butter jobs are weddings. Couples most often request that she play Pachelbel's Canon in D, which she finds a bit tedious.

She spent the summer taping three releases for Musicland's Excelsior label, including Celtic, Irish and folk tunes; romantic classics; and Renaissance music. It's that range she'll offer in her performance with Turtle Island String violinist and Windham Hill recording artist Tracy Silverman of Oakland. (He also plays several cuts on "City of Gold.")