Jazz bassist William Parker celebrates his 65th birthday at the Painted Bride

When William Parker picks up his bass at the Painted Bride on Saturday, it will ostensibly be a celebration of his 65th birthday. For Parker, though, the show is just one more opportunity to reunite with old friends and collaborators and create jazz music in the moment, just as he has on countless occasions throughout a career that's lasted more than four decades. It's also a chance, he realizes, to introduce himself to new listeners who may not be aware of his long list of notable, if often under-the-radar, accomplishments.

"The profile of this music is very low, so there are constantly people just finding out about the music for the first time," Parker says. "No matter how old you are, since you're deep in the weeds here, you can always be discovered for the first time when you're 60 or 65 or 70."

For those in need of an introduction: The Bronx-born Parker made his entrance into New York's avant-garde jazz scene at the dawn of the "loft jazz" era in 1971, when the music's most forward-leaning artists were playing in makeshift places in industrial loft spaces in SoHo. He spent most of the 1980s as a member of legendary pianist Cecil Taylor's band, and later was a member of the David S. Ware Quartet, one of the most notable ensembles of the 1990s. He's also played a key role in the experimental jazz and arts Vision Festival, founded by his wife, dancer/choreographer Patricia Nicholson, which will celebrate its 22nd anniversary this year.

Along with being a tireless player and improviser, Parker is a prolific composer, as evidenced by the volume of material he's released in just the last five years–a three-CD set of music for large ensembles, eight CDs of his "Wood Flute Songs," six discs' worth of unreleased early recordings, and a number of single-album releases.

For 2017, he already has two releases in the pipeline: a duo album with the late Italian bassist Stefano Scodanibbio, recorded in 2008, and a two-CD set featuring two different quartets.

Saturday's performance will be something entirely different, a Phillycentric sextet organized by saxophonist and bandleader Bobby Zankel, who has known Parker since 1973 and who shared the stage with him at Carnegie Hall in 1974 as part of a Cecil Taylor-led ensemble.

"We have a very long history," Zankel says. "I've had the good fortune to be a part of his evolution as an artist, a bass player, a composer, and a human being. He's more than just a bass player. He's an artist; he's a magician. He's like a medicine man, and he's developed a way of playing that's totally personal and grounded in the history of the instrument."

The sextet will also feature pianist Dave Burrell, another loft-scene veteran whose 75th birthday Parker helped celebrate in a similar concert at the Bride in 2015; trombonist Steve Swell, a free-jazz veteran with whom Parker has played in a number of contexts; drummer Muhammad Ali, a longtime collaborator along with his late brother Rashied Ali, another key figure of the loft era; and violinist Diane Monroe, who first worked with Parker in 2014 during the world premiere of the bassist's suite "Flower in a Stained Glass Window," dedicated to the Rev. Dr. Martin Luther King Jr.

"When you have a rapport with a person, you want to repeat it," Parker says. "It's like having a good meal and wanting to go to that restaurant again, visiting an aunt or uncle where you talk about things that stimulate you every time you see them. It's the same in playing music. It's always great to come together because there's the anticipation that something great is going to happen and the mystery of what it will be."

At an age when many are settling into retirement, Parker will entertain no thought of slowing down. His voice still betrays the excitement of each new musical experience.

"Every time you play, it's like being the pilot of a plane," he says."The audience are like your passengers. You have to take off and land safely, but you're taking them on this journey. Each concert that you play is a celebration. If it happens to be dedicated to your birthday, then it's that, but it's a real celebration and an honor and a privilege when you're able to play music together."