The Sound of Diversity : Performances: The festival will include straight-ahead jazz offerings for the first time.

Michelob Street Scene producer Rob Hagey doesn’t think straight-ahead jazz will lure many extra music fans to this weekend’s two-day musical smorgasbord in the Gaslamp Quarter downtown. But he believes it will enhance the atmosphere and perhaps convert a few people to jazz.

Hagey has booked saxophonist Bennie Wallace, trumpeter Jon Faddis and pianist Harry Pickens as the only straight-ahead jazz performers among a cast of more than 50 acts for this weekend’s Street Scene (aside from a 1989 appearance by pianist Eliane Elias, there hasn’t been any straight-ahead jazz at the festival before). “We really want to see the event grow, to show many different types of music. I’ve been wanting to put some jazz in, and I finally found the right venue.”

Wallace, Pickens and Faddis will play at the 250-seat Hahn Cosmopolitan Theatre on 4th Avenue, which has rarely been used for live jazz, although Hagey thinks it offers a perfect, quieter indoor setting not far from Street Scene’s busy outdoor stages. Like last year’s event, this year’s Street Scene also includes pop-jazz, in the form of saxophonist Richard Elliot. And as a welcome footnote to the Street Scene that is not actually part of the official program, on Friday and Saturday nights the Horton Grand Hotel nearby is presenting jazz vocalist Kevyn Lettau, whose debut, self-titled album was released earlier this year.

Wallace, 40, hasn’t released a new recording in the United States since a pair in 1988 (“Border Town” and “The Art of the Saxophone”). This weekend, he will unveil a different band than the one he brought to San Diego last year. With drummer Alvin Queen replacing John Vidacovich, Wallace said the direction of his music has changed substantially.

“This is more a jazz band. The change of drummers changed the color of the band more than anything,” Wallace said. “John Vidacovich is a wonderful New Orleans groove player, playing second-line things and tangos, those hybrids of what we used to call R&B; and jazz grooves. Whereas Alvin is a great jazz drummer in the tradition that goes back to the 1950s.” Guitarist Jerry Hahn and bassist Bill Huntington round out the group.

One reason Wallace hasn’t recorded in awhile is that he has devoted much of his time to writing movie music--one of his main objectives in moving to Los Angeles from New York 18 months ago.

Wallace has often been identified in the press as a jazz man with New Orleans roots.

“When I did ‘Twilight Time’ (his 1985 recording), the idea was to base the compositions on different kinds of folk forms from the south,” Wallace said. “All Night Dance,’ is a shuffle that could come from Tennessee and Georgia, but not New Orleans. ‘Tennessee Waltz’ is real obvious. But if they think I’m trying to pass myself off as being from New Orleans, I’m not guilty.”

On tenor, Wallace has a fleeting, elusive sound that works well in a straight-ahead setting--and Wallace has worked in some prestigious ones over the years, beginning with a 1977 trio that included bassist Eddie Gomez and drummer Eddie Moore. Later, he played with Chick Corea, Elvin Jones, Dave Holland and Tommy Flanagan.

Wallace is an adventurous composer with a Thelonious Monk-like flair for odd, meandering melodies and surprising chord changes. His improvisations are just melodic enough to hold less experienced listeners, but he’s not afraid to slide and slither through less structured territory too.

Where Wallace has a distinctive sound, Faddis, 38, is something of a chameleon--a quality at once annoying and intriguing. A protege of Dizzy Gillespie, Faddis has also been known to mimic the minimal, electric style of present-day Miles Davis; play a muted blues tribute to Louis Armstrong; lend precise, clear-as-a-bell fluegelhorn to a ballad; take a turn as a rapper on “Rapartee,” his hip-hop capsule history of jazz; and race through an up-tempo number, with a nod to Gillespie’s vintage be-bop.

“It’s something I always tried to do, sound like Dizzy,” admitted Faddis, who lives in Teaneck, N.J. “The down side is, people don’t always hear me as Jon Faddis. I think there are still some ties (to Dizzy), especially when I play fast tunes. But I think, on other things, I’m starting to develop my own style.”

Faddis, who was born in Oakland, joined Lionel Hampton’s band out of high school, played regularly with the Thad Jones-Mel Lewis Big Band in New York City and has also made music with Roy Eldridge, Charles Mingus and, of course, Gillespie.

Like Faddis, San Diego pianist Pickens is a versatile piano stylist, capable of quoting influences into his playing, from ragtime, stride and Fats Waller to such moderns as Monk and Oscar Peterson. Pickens’ last recording was a 1986 album with the precocious, young New York sextet, “Out of the Blue.” Since then, he has spent much of his time teaching motivational seminars and working on related writing projects, while performing occasionally in local clubs.

Saxophonist Elliot, who plays the Street Scene’s KIFM Stage at Sixth and Island from 9:30 to 10:45 on Saturday night, has always been up front about his desire to reach a mass audience. His music tends toward appealing, honeyed melodies ladled over a mild-mannered, studio-perfect carpet of electric and synthesized sounds. Recordings such as the 1989 “Take to the Skies” and last year’s “What’s Inside” have sold extremely well.

In concert, however, Elliot provides sparks that don’t fly in the studio. Before going solo in 1988, he played sax with Tower of Power, the legendary San Francisco Bay Area funk band. He often brings this gritty sensibility to bear in his live shows.

At Friday and Saturday night’s 7:15 straight-ahead jazz concerts at the Hahn Cosmopolitan Theatre, a solo performance by Pickens will be sandwiched between sets by Faddis and Wallace. Faddis will be backed by Pickens and San Diegans Bob Magnusson on bass and Jim Plank on drums. Lettau’s sets at the Horton Grand Hotel-- not officially part of Street Scene--will begin at 8:30 Friday and Saturday nights.