Raitt fronted her longtime touring band, augmented by Hammond B-3 whiz Mike Finnigan, who took the mic for a spirited rip through Ray Charles' "I Got News for You" that allowed the leader to stretch out most satisfyingly on guitar. Raitt's slide provided a sharpened edge to John Hiatt's "Thing Called Love" and Bob Dylan's lament "Million Miles," one of four Joe Henry-produced tracks that are Slipstream standouts.
Along with blueswoman swagger, Raitt's appeal is built on a nuanced, probing way with broken-heart songs. The crowd-pleaser was the soft ballad "I Can't Make You Love Me" from her biggest seller, 1991's Luck of the Draw. Better still was a part spoken, part a cappella reading of John Prine's "Angel From Montgomery," delivered in a full-of-feeling alto seasoned by the nearly four decades since she first recorded it.
Foo Fighters leader Dave Grohl, said to have twice left bartenders a $1,000 tip on a recent stay in Philadelphia, is often called the nicest guy in rock. His female counterpart is surely Raitt, who on Saturday thanked by name her sound man, guitar tech, and concert promoter, as well as singling out all her band members several times over.
She talked about riding bikes along the Schuylkill with guitarist George Marinelli the day before, and dedicated songs to Philadelphia institutions such as the Rhythm & Blues Foundation, American Friends Service Committee, and DJ Michael Tearson. And after closing with a reggae groove on "Have a Heart," she asked her audience to do her a favor. "It looks like an auction," she said. "But it's an election. Go vote."
The life force that is gospel powerhouse Mavis Staples, 72, opened with a roaring set including a rousing version of the Band's "The Weight," a hushed take on the title cut from her 2010 album, You're Not Alone, and a spontaneous-seeming "Will the Circle Be Unbroken?" with Raitt, whom she called her "baby sister." When the headliner returned, she called Staples "an intergalactic treasure," took a look around the 155-year-old opera house, and observed: "Mavis really classed up this place, didn't she?"
Contact Dan DeLuca at 215-854-5628, email@example.com, or follow on Twitter @delucadan. Read his blog, "In the Mix," at www.philly.com/inthemix.