NEW YORK -- It was five years ago, and alto saxophonist David Sanborn was facing one of the most important choices in his life. He'd been around the world. He'd played in every blues dive from San Francisco to Houston, and major concert venues from Montreal to London where thousands cheered his name. He'd played on hundreds of recording sessions, traded licks with Paul Butterfield, funked with Stevie Wonder, rocked with Bruce Springsteen, toured with the Rolling Stones, made a friend in Rickie Lee Jones, James Brown, the Temptations. He'd been with them all. Him and the horn. Especially the horn, because sometimes he was so high he wasn't there and the horn seemed to play itself.

All his life, the horn had been a way out for him. Polio at age 3 confined him to an iron lung for a year; for a year after that he was paralyzed from the neck down, and today he has a barely noticeable bit of atrophy in his left arm and right leg. But when he was 10 he heard Ray Charles on the radio with an alto sax man named Hank Crawford and he was knocked out. So young David Sanborn picked up an alto saxophone and wandered into the no man's land of black rhythm and blues joints in his home town of St. Louis, Mo. He played with people whose music made them feel free, blacks who poured their passion and soul into the music, and he too learned to pour passion and soul into his horn.

In the years that followed he also learned to pour "four to five" bottles of wine down his throat a day, and various drugs. Five years ago it caught up with him, and for the first time in his life his horn couldn't help him. He asked himself, "Do I want to get high, or do I want to be a musician?" He decided on the latter, and quit drugs, alcohol, even caffeine. And while he was at it he quit being a sideman too.

Which is why Sanborn is sitting here today in his tiny Upper West Side apartment munching a carrot, five years and three Grammy Awards later, detoxed and healthy, host of a nationally syndicated jazz radio program, frequent guest with David Letterman's "Late Night" band, and in the middle of a tour as the country's top jazz-fusion saxophonist with a new album, "A Change of Heart." He performs at the Merriweather Post Pavilion tonight.

"Some say I'm too pop, too mass appeal," Sanborn says. "Others look on me as not mass appeal enough. But I play music on my records that I like. The concept I play in might not be particularly adventurous to some people, but I feel good about what I do. I gotta play what I gotta play. I have to be true to myself."

It's afternoon at Sanborn's apartment, which he laughingly calls "my dressing room." It's crammed with saxophones, books, a waist-high juice-maker packed into a metal case on wheels that he takes on the road, and a Yamaha grand piano with a music book opened to a jazz version of "My Favorite Things." His Grammy Awards are lined rather unceremoniously on the windowsill, under the air conditioner blasting overtime, right next to the small dining room table that seats only two. Sanborn, 41, divorced, lives alone. His son Jonathan, 21, is a bassist attending the Berklee College of Music in Boston.

"It's funny," he says, sitting at his table with carrot in hand. "People come up to me now asking me about the old days, what it was like. I don't feel old." Neither does he look old. Darkly handsome and thin, with a twinkly wise-guy grin and an outrageously hip stage presence -- horn twisted to the side of his body in total funk repose -- Sanborn could easily pass for 30 unless you look close enough to see the twinges of gray in his hair.

He got his start in the late '60s, playing his first professional gig at age 15 with bluesman Albert King in St. Louis, later joining the Paul Butterfield Blues Band in San Francisco. He moved east to Woodstock, N.Y., and in the early '70s played with Stevie Wonder for two years, also touring with the Rolling Stones 1972 tour, one of the most memorable in rock history.

"That was wild," Sanborn says, recalling the Stones tour. "The group was at its height. Guys like Truman Capote, Terry Southern, hung out, partied, wrote articles for Rolling Stone." Back then drugs flowed freely in the part of the business he saw. "In the early '70s, drugs seemed harmless," he says. "It was like a big party. But by '74, '75, the drug scene got ugly. You'd be at a party and some guy would get up and say" -- and here Sanborn stands up, arms raised, and mimics a grinning maniac -- " 'Wow man! Woooooow! You got any more? WOW!' And that guy would be me," he laughs.

But while he lived in a world of rock (his solo on James Taylor's "How Sweet It Is" remains a standard), Sanborn is, in essence, a jazzman -- one who understands the intricacies of jazz and translates them into accessibility in the tradition of rhythm and blues saxophonists Maceo Parker, Junior Walker and the late King Curtis.

Sanborn's playing embodies all of those influences, but his soaring, biting sound, and his ability to infuse so much passion, anger and humor into his playing -- to the point where it seems his alto can't contain what he has to say -- is what distinguishes him from today's syrupy pop horn men like Kenny G., Najee or even Grover Washington, players who lose the gutbucket blues sound when making the pop transition. His studio sound is patented, sought less successfully by studio horn men everywhere, and somehow more closely aligned with the playing of alto jazzmen Phil Woods and Paquito D'Rivera.

"I don't particularly think I'm an innovator," Sanborn says. "I have a certain way of playing that may have influenced some things. My music is more body-oriented, directly emotional, so in that sense it's more rhythm and blues ...

"The music I make on my own, I would not call jazz. That's not to say I can't play in that environment. I happen to listen to a lot of be-bop. It's intellectually and emotionally inspiring to me. To me, the ultimate musician is {tenor saxophonist} Wayne Shorter. Everything he plays, it sounds like it's the first time he ever plays it. He has such a freshness -- there's an innocence to his playing."

Last month Sanborn, who penned the scores for "Soul Man" and "Psycho III," filmed a traditional jazz segment for a "Showtime" variety show hosted by Herbie Hancock. The special, titled "Coast to Coast," will air Aug. 29 and features a free-blowing jam session with Shorter and Sanborn, Hancock, and Joni Mitchell and Bobby McFerrin. "It was one of the most enjoyable experiences I've ever had in my life," Sanborn says.

He's a shepherd of traditional jazz, his popularity lending considerable weight to his radio program, "The Jazz Show With David Sanborn," begun in January 1986 and produced by NBC radio. The two-hour weekly segments, taped in New York, are aired by more than 140 stations in most major markets -- except Washington. WBMW carried the program locally until last Sunday, but dropped it in favor of a new format.

"It's important," says Sanborn, who grew up in clubs where some of today's jazz standouts got their start, "that the tradition of jazz and what it stands for be maintained in some way."