How does one describe Chaka Khan? The late jazz legend Miles Davis once compared her vocals to his trumpet. She’s been called the "Queen of Funk-Soul," but to lump her into one category doesn't cut it for the 10-time Grammy winner.

“I think we should pass that title on to somebody else, because I think I've grown far beyond that,” the singer said during a phone interview on Thursday.

Khan, along with fellow R&B legends Dionne Warwick and Valerie Simpson, will be honored with Trailblazer awards at tonight's second-annual Howard Theatre gala and benefit. A tribute to the honorees, with performances by Marsha Ambrosius, Yolanda Adams, BeBe Winans and Sheila E., begins at 8 p.m.

Chaka Khan, along with Dionne Warwick and Valerie Simpson, will be honored at the Howard Theatre on Friday. (David Surowiecki - GETTY IMAGES)

The award recognizes the contributions of female performers in shaping today's music industry. “I don’t feel like I deserve all this,” Khan said. “It’s really a lovely thing and a pleasant offering what they’re doing and I accept it, and it’s a surprise. I’m always surprised when something like this happens. You’ll never get used to it.”

The award from the Howard comes during Khan's 40th year in music, an anniversary the singer will mark by releasing “The iKhan Project” on July 2. The album will incorporate eight genres of music, including country and gospel, and new songs in addition to reinterpretations of original recordings. Khan’s first album “Rufus” was released July 1, 1973.

“The music is going to be for the most part unplugged and very earthy and soft and sweet with powerful messages,” she said. “For 40 years, people have been telling me that I am anointed, I have an anointed voice, and ‘When am I going to start singing for Jesus?’ Well, as far as I’m concerned, I've been singing for Jesus since I've got this voice from God.”

With the benefit of four decades as a performer, Khan said much of today's music can come across like a circus, though she respects an artist's right to free expression. “These are kids, these are young people trying to express themselves on many levels, so I can’t get pissed at it, because they’re expressing themselves and I love self-expression from anybody.”

In January, Khan was honored at the BET Honors; this summer, she will be inducted into the Apollo Theater Hall of Fame and have a street named in her honor in her hometown of Chicago. Khan will return to D.C. for a June 8 performance at the Capital Jazz Fest at Merriweather Post Pavilion.

When she’s not performing, she may be spending time with her grandchildren or working on behalf of her charity, the Chaka Khan Foundation. Before pursuing a career in music, Khan contemplated becoming a nun (she attended a Catholic school as a child) or an anthropologist. “I love people, human beings and what makes them tick and why that makes them tick,” she said. For many, including Khan, music is that catalyst. “I think that through music, we can say amazing things that can make amazing things happen.”