(CNN) -- Herbie Hancock has been here before.
Herbie Hancock has won 10 Grammys -- and could add more to his take this year.
The famed jazz pianist has 10 Grammy Awards to his credit -- for such works as "Rockit," "A Tribute to Miles" and "Gershwin's World" -- not to mention nominations for several more. He's no stranger to other honors, having won tributes from organizations ranging from MTV to the National Endowment for the Arts.
But, he says, it was still a shock to hear his name announced among the nominations for Grammy's 2007 album of the year for his album "River: The Joni Letters" (Verve).
"I was blown away by the nomination," he says in a phone interview from Los Angeles.
But, he adds, in a way it's appropriate.
"It's so timely. It's the 50th anniversary of the Grammy Awards, and the Recording Academy and the Grammys were designed in order to expose a variety of music to the public. In a way [this year's nominations] are a way to get back to the purpose of what the Academy is about in the first place," he observes, noting that the five album of the year nominees -- "River," Amy Winehouse's "Back to Black," Vince Gill's "These Days," the Foo Fighters' "Echoes, Silence, Patience & Grace" and Kanye West's "Graduation" -- are from five different genres.
"I'm just fortunate that one of them happens to be for my record," he says. The awards are scheduled for Sunday.
On the one hand, "River" would seem to be a natural for a Grammy nod, based on the Recording Academy's politics. Hancock, 67, is a musical eminence with decades of professional experience, including stints with Miles Davis and his own V.S.O.P. quintet. His use of electronic keyboards in jazz was groundbreaking, and he's even had a couple of hit singles.
The Recording Academy likes to honor longtime veterans almost as much as it does newcomers, as it has with Ray Charles, Tony Bennett and Eric Clapton -- all of whom won album of the year in the last 15 years -- so Hancock would seem to have an edge over his fellow nominees for the big honor.
On the other hand, "River" is an unapologetic straight jazz album, with unusual harmonies and expansive running times -- not exactly a radio-friendly multiplatinum smash. In fact, in the history of the Grammys, only one pure jazz album -- Stan Getz and Joao Gilberto's 1964 "Getz/Gilberto" -- has won the big prize, one less than the number of comedy albums that has done so.
Hancock says "River: The Joni Letters" came about because of a suggestion from Verve executive Dahlia Ambach Caplin, who asked what Hancock was going to do for his next jazz record following 2006's somewhat pop recording, "Possibilities." Knowing about Hancock's friendship with Mitchell, the idea came up of doing an album of Mitchell songs, many of which have jazz underpinnings.
Hancock worked with producer Larry Klein, Mitchell's ex-husband, on the record. "I knew he'd have an excellent understanding of Joni and her music," Hancock says.
The pianist was also accompanied by a crack band -- saxophonist Wayne Shorter, bassist Dave Holland, guitarist Lionel Loueke and drummer Vinnie Colaiuta -- and, on some cuts, joined by a spectrum of vocalists that included Norah Jones (singing "Court and Spark"), Corinne Bailey Rae ("River"), Leonard Cohen ("The Jungle Line") and Mitchell herself ("Tea Leaf Prophecy").
Hancock says the choice of songs -- some well-known, others well-hidden -- was deliberate.
"We didn't want to look for things that were the most popular," he says. "We wanted some obscure songs."
Though the famous vocalists' names have created interest in the album, on a number of songs, the instrumental arrangements tell the story. On the much-covered "Both Sides Now," which Judy Collins took to the top 10 in 1968, Hancock and his group create a wintry soundscape highlighted by piano and drum brushes, giving a wisdom to the song's (unheard) lyrics, written when Mitchell was in her mid-20s.
"I didn't start out thinking of the lyrics at all," Hancock says. "I started off with the melody ... and ended up with something kind of interesting."
But that's not to say he wasn't aware of the words and their tale of changing perspective ("I've looked at love from both sides now/ From give and take and still somehow/ It's love's illusions I recall/I really don't know love at all"). "I know Joni and how her songs come from the lyrics," he says. "Whatever I do has to relate directly to the lyrics."
For Hancock, "River: The Joni Letters" is another step in his growth as an artist. He resists stereotyping and says that, even at 67, there's plenty left to learn.
"I don't pay attention to pigeonholes," he says. "The more I can expand myself, the more I can find a common ground between myself as a human being and other human beings, the more material there is and the more ideas there are -- the more ways of expression there are available to me." E-mail to a friend