IN THE harmonica world, musicians are represented by two separate but equally important groups: the blues players who dominate the limelight and the jazz players who settle for what they can get. This is the jazz players' story.

"I really just wanted to be a great saxophone player. So I practiced all the time on the harmonica, and, I think, instead I just became a really good harmonica player," says Damien Masterson, one of eight performers slated to blow his chromatic harmonica at the first annual West Coast Jazz Harmonica Summit Aug. 10 at the Digital Media Factory in Santa Cruz. "It's a very difficult instrument, and there aren't a lot of people who play it. I think most of the people who play it got bored with the blues harmonica and moved on to jazz, because it's more challenging and interesting."

Masterson's chromatic harmonica is the hallmark of the jazz harmonica clique and the only kind that will be featured at next week's summit. Long, fat and with a full range of octaves, it's a much different beast from its smaller, single-octave cousin, the diatonic, or blues harmonica. For Summit organizer Slim "Slide Man" Heilpern, it's a true musician's instrument, not just a noisemaker for jail cells and bayou porches.

"The chromatic harmonica is a very unique instrument," he says. "Some people really don't get it, and others just latch on to the style and go with it."

Heilpern isn't expecting a stampede of folks to show up for his shindig. After accounting for room for the video equipment with which he plans to document the performance, he figures the Digital Media Factory only seats 100, and he expects plenty of tickets to be left at the door. But those who do show up, he says, will get an up-close-and-personal view of a seldom-seen nook of the jazz world.

"It's hard to sell a lot of tickets to this kind of thing," says Heilpern. "I think a lot of the musicians are just looking forward to hanging out with each other and hearing some great music."

Yet jazz harmonica music is not completely obscure. Toots Thielemans, undoubtedly the most recognized name in the genre, is famous in both harmonica and jazz circles. And, though few realize it, music legend Stevie Wonder is considered one of the best jazz harmonica players of all time. On songs like "True to Your Heart" and "Hey Harmonica Man," Wonder's knack for the mouth harp is unmistakable.

For one summit performer, it was the mastery of Thielemans that cemented his interest in the chromatic harmonica and what's kept him practicing for 30 years.

"I had been a blues player for years, but I'd studied jazz. I finally saw Toots play live in 1979, and that night I decided that was the sound for me," says Jon Eriksen, who weaves a decidedly Latin vibe into his jazz expressions. "When I think of a blues harmonica, I compare it to a Strat or Les Paul electric guitar. But a jazz harmonica I think of as a big hollow-body guitar. We all got the little harmonica for a toy when we were kids, but most of them ended up back in the toy box. To me, it's just amazing to see someone who actually put the time into perfecting an instrument like that."

THE WEST COAST JAZZ HARMONICA SUMMIT swings on Aug. 10 at 7pm at Digital Media Factory, 2809 Mission St., Santa Cruz. Tickets are $20 and available at www.jazzharmonicasummit.com or 800.838.3006.

Send a letter to the editor about this story.