Go to a Charlie Hunter show and you can usually spot the newcomers. They're the ones looking for the bass player or the keyboard player. But the varied sounds they can't place are coming from Hunter himself.

"I occupy the center," Hunter says. "Basically, I handle both the harmony and bass line roles with the guitar. It's an open, less cluttered sound. And it gives the three of us more space to move around within the music."

Influenced by the organ trios of Jimmy Smith, Larry Young and Big John Patton, Hunter developed a different take on the classic format, rounding out his guitar with saxophone and drums. This Thursday, Hunter brings his current trio, with John Ellis on saxophone, flute and bass clarinet and Derrek Phillips on drums, to The Stone Church in Newmarket. They'll perform selections from their current CD, Friends Seen and Unseen, released last year on Ropeadope Records.

Hunter was exposed to music via his mother, who worked repairing guitars while he was growing up in the San Francisco Bay area in the 1970s. Immersed in a myriad of musical styles that were representative of the area's cross-cultural population, he was "exposed to everything from the Dead Kennedys to P-Funk to Art Blakey," he recalls. Just absorbing the sounds was an education unto itself.

"You have all these musical cultures living together, and their music gets semi-assimilated into this non-polarized state of being where hybrids are free to grow, and there are all of these genres and cross genres to play in and around."

Hunter attended the same Berkeley high school whose music program produced saxophonist Joshua Redman and pianist Benny Green. But the music program wasn't the thing for Hunter. "I really wasn't an institutional-type person. I had to go out and do my own thing." Part of that thing was assimilating his own influences, from classic organ trios to the music of Stevie Wonder, Marvin Gaye, Muddy Waters and Buddy Guy to the jazz guitar work of Joe Pass and Tuck Andress.

Instead of school, Hunter took a different approach to honing his skills. "After high school, I spent a lot of time working as a street musician. Eventually, I made my way to Europe, where I played solo guitar on the streets, and also a lot of acoustic bass with other street musicians. Playing in this type of situation helped me to develop the playing approach I use today."

Hunter's initial national exposure came 10 years ago via his debut CD Bing, Bing, Bing on Blue Note. This was the recording that defined the Charlie Hunter Trio sound, a seamless blend of jazz, soul and blues music with added touches of Latin and reggae. Soon after, a second horn was added, expanding the group to a quartet. But eventually, Hunter decided that the trio format was more appealing.

"Part of it was a financial consideration," Hunter says, "but I also found that the quartet was a little constricting. With the trio, we have the ability to create a big sound, yet stop on a dime and move into a quieter, more subtle sound."

His trio colleagues have been with Hunter for about five years now. Asked what his trio colleagues bring to the group, Hunter says "John Ellis is a remarkable horn player. He has a deep well of imaginative ideas that he draws from. I've learned a lot from him in terms of harmony and solo development. Derrek Phillips is a terrific drummer who possesses great time and feel."

Hunter also deeply appreciates his trio mates' openness. "Both of these guys have strong jazz knowledge and pedigree, without the dogma. They are willing to, and can, play anything."

That open attitude prevails on the current CD, which is a vintage Hunter Trio recording in the sense that all of their various influences blend together remarkably well. Listening to the CD, I was reminded of a comment that noted jazz bassist Rufus Reid made in a workshop at the University of New Hampshire. He said that jazz musicians of today need to have a "core of tradition, but no barrier to explore." This is something that Hunter's trio does well at all times. On the CD, there's a fair amount of New Orleans in the overall sound (subtle second-line grooves, Neville Brothers-style funk, etc.), something that Hunter readily acknowledged. "We've played a lot in New Orleans, and John Ellis is originally from there. So it's always creeping in. It's a big part of our sound." The CD itself offers one highlight after another, with Ellis and Hunter playing inventively over the rock-solid, yet flexible grooves of Phillips.

As for what to expect on Thursday, Hunter says "All of our shows are different. We keep it loose. We tend to go where our imaginations take us. But we do make sure that we're making a connection with the audience. At every show, they're a part of our community, so we want to make sure that they enjoy the ride that we take them on." The group considers it their mission to expose people to the music of the past who might not be exposed to it anywhere else.

"If our mission succeeds, hopefully we'll have helped to turn a generation of people on to a much more spiritually and soulfully executed music than what gets played on MTV," says an optimistic Hunter. "It's culturally the duty of the younger generation to help the music evolve. We wouldn't be doing our jobs if we didn't."