"We've developed a sound that we're all very attached to now," she says. "When we do projects with other people, it's pleasant and lovely, but it's very foreign to us in a certain sense, because the level that we listen to each other and react to each other is something we've gotten used to.
"I'm a singer that doesn't have a huge voice, so if I'm with musicians outside of my normal band — players without that sensitivity who aren't used to that aesthetic — it's a really uncomfortable thing for me."
While so many contemporary jazz vocalists habitually jump from project to project and hire endlessly revolving casts of backing musicians, the strong-voiced Sutton tightly embraces what works best — a solid, ever-evolving quartet-style collaboration with pianist Christian Jacobs, bassists Trey Henry and Kevin Axt, and drummer Ray Brinker.
For over 15 years, and through nine albums, Sutton has worked closely with this band, touring extensively across North America and Europe, carefully steering into new musical directions with each recording. Listening to their most recent album Desire (Telarc), it's clear the chemistry between them is stronger than ever.
"These guys are my business partners," Sutton says. "It's the band I tour with, and the band who record with me. What we have is really a very different thing to many jazz artists. It creates both an ability to improvise and stretch, and also an ability to be very together on things — to communicate and adjust to each other in ways that you can't with a pickup band.
"We seem like one voice, and it took years to develop. Maybe around year nine, the sound of the band started to reflect not really what I had in mind, or what another member had in mind, but rather another thing entirely. We all recognized it. It was no more me than anybody else."
This spring, the group received its second consecutive Grammy nomination for "Best Vocal Jazz Album" — the latest honor on the heels of a JazzWeek award for "Vocalist of the Year," and consecutive nominations for Jazz Journalist Association awards.
In recent years, Sutton and the band have headlined at Carnegie Hall, the Hollywood Bowl, the Kennedy Center, and Jazz At Lincoln Center, among many notable jazz venues around the country.
With their lengthy experience comes flexibility and range. "We've been together for over 15 years, and all of our music is collaborative," Sutton says. "We are co-arrangers of everything and full partners in the band. We choose from over 150 arrangements for any show. Nothing's off the table, and nothing's on the table. When we soundcheck at a venue, we try to feel what the space is, and then we try to take stock of what the moment is going to be.
"It also has to do with how everyone is on a given day, like where I may be vocally, or what other band members may feel physically. Really, it's always a band credo that we never do the same set of music twice. When we do two shows in one night, we won't repeat any of the songs at all."
Desire features an almost sinister rearrangement of Cole Porter's "My Heart Belongs to Daddy," as well as a new take on Johnny Mercer's and Hoagy Carmichael's "Skylark" (a track delicately propelled by Brinker's feathery brush and mallet work and quietly sizzling cymbal accents). It also includes recited passages from The Hidden Words of Bah'u'llah, a sacred Baha'i text.
Sutton doesn't know exactly what she and her colleagues might throw into their set list for their two concerts this week, but they're confident festival-goers will connect with the music regardless.
"My band and I are most impressed with the overall scope of the Spoleto Festival," she says. "It's what an arts festival really should be, with people passionate about dance, theater, and all of the arts being a part of it.
"That's definitely where we're coming from."