As one of the most popular draws in popular music—not only here, but around the globe—Diana Krall makes a special return to the Sonoma Jazz + festival this weekend. The alluring jazz songstress appears on May 24.

Introduced to the jazz world with a pair of intimate trio albums, the blonde Canadian branched out in 1999 with When I Look in Your Eyes. Orchestrations by Johnny Mandel along with Krall's sultry vocals and Grace Kelly–like countenance took the album's record sales into the stratosphere, and the album won Krall her first Grammy award.

Ironically, when she was discovered by jazz drummer Jeff Hamilton in her homeland, she was pounding the keys—she didn't really sing. While doing solo piano gigs at a restaurant, jazz greats the L.A. Four, with Hamilton and legendary bassist Ray Brown, showed up one night; they were performing in a club down the street. The next evening, the entire group had dinner at Krall's parents' house and, as she tells me on the phone, "they talked about my future. It was exciting."

I ask if it was true that there was hesitancy on her part to start singing, and after a very long pause, she answers. "Uh . . . yeah. I wanted to sing like Sarah Vaughan! At 20 years old, I didn't know my style. I'd think, 'If I don't sound like Sarah, I'm not any good.' I still don't have the greatest instrument in the world. I guess it's unique, I don't know."

She stops and reconsiders. "It's not unique," she laughs. "I sound like my grandmother!

"When you're young, you try to sound like somebody else," she continues. "You're trying everything. I finally decided I was just gonna sing." She says that she only began to relax about her vocals during the When I Look in Your Eyes sessions. "I'm never satisfied, but I started to feel more comfortable."

Krall's early piano influences include the barrel-house style of Fats Waller and the stride playing of Hank Jones. Teddy Wilson, Red Garland and Oscar Peterson are among her other favorites. The music of Bill Evans took her through high school.

I mention that I've certainly heard the Evans influence, but that Fats Waller had eluded me while listening to her music, until I heard the bass line from her recording of "I Can't Give You Anything But Love."

"That's exactly where I got it," she says.

Krall's also listened to a lot of Elton John. "I just saw him [perform]," she says. "There's no one like him. He's amazing, especially doing boogie-woogie. He dedicated a song to me!"

Elton John's estate is where Krall tied the knot, in 2003, with Elvis Costello, in a pairing that reminds some of the Julia Roberts and Lyle Lovett coupling. These not-so-strange-bedfellows, along with their young twins, have managed to carve out a family life that involves constant touring and endless recording by both parents. They've also influenced each other's music. In 2004, Krall released The Girl in the Other Room, featuring, for the first time, songs she had written, one with lyrics from Costello. It also featured the single "Temptation" written by Tom Waits, a record still on the playlists of local radio stations.

But her core repertoire remains the standards. I ask how hard it is to record a song like "I've Got You Under My Skin," the Cole Porter classic forever remembered as one of Frank Sinatra's most loved records. "Every tune in some quiet way is a tribute to somebody else," she says. "Everything I listen to is put into what I do.

"I know Sinatra's version like the back of my hand, every bump and move, I've listened to it over and over again. The fun of it is to do something different, but to keep a little of its spirit. Frank's version is very upbeat. We took it down and changed the lyric. I've always messed with tempos—tempos are everything. You can change the whole mood of a piece. You can go from one story to another just with a tempo change."

Now 43, marriage and motherhood have slowed Krall's tempo a bit, but a new album is in the works, and after her show in Sonoma, she's off to Europe for jazz festivals throughout the summer. She's not concerned about the busy schedule. "I never think anything to death," Krall says easily. "I have my own quiet way of thinking about things."

Diana Krall appears Saturday, May 24, at the Field of Dreams as part of the Sonoma Jazz + series. 151 First St. W., Sonoma. The incredible duo of Taylor Eigsti and Julian Lage open the show at 6:30pm; Krall plays at 9pm. $60–$110. 866.527.8499.

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