Tradition versus innovation. That is the essential dynamic that makes jazz such a vital American art form. It is also the essential dilemma that underscores the experience for audiences, musicians and officials at the Monterey Jazz Festival.

At this year''s 44th annual MJF, dedicated as a celebration of the 75th birthday anniversaries of protean jazz giants Miles Davis and John Coltrane, no two performers better exemplify the continued promise and contradictions in jazz than saxophonist Branford Marsalis, this year''s festival showcase artist, and his brother trumpeter Wynton Marsalis, arguably one of the most important and influential jazz musicians of the last 20 years.

Both artists embody the polar extremes of jazz as it is played and debated. Although he is as technically accomplished and well-grounded in the history and traditions of the form as any jazz musician, Branford Marsalis has embraced with exuberance the broadest possible spectrum of musical expression. From straight-ahead jazz, to hip-hop, funk and pop Marsalis has refused to recognize any boundaries. While no apologist for his musical choices, Marsalis has acknowledged that his decision to serve as band leader for Jay Leno''s Tonight Show Orchestra, and to perform and record with such musicians as Sting and the Grateful Dead, has alienated the purists.

"The jazz world always hated me because I''ve broken so many of the rules," Branford admits to Gary Giddins, in the 1998 book, Visions of Jazz.

With Branford''s special guest appearance Friday evening with the McCoy Tyner Trio, the audience can expect to hear Marsalis at his mainstream best. As part of Coltrane''s groundbreaking quartet of the early ''60s, McCoy Tyner will likely resurrect many Coltrane classics, affording Branford an opportunity to showcase his superb instrumental and improvisational skills. Branford will also be performing in a unique duo setting Saturday evening with pianist and composer Billy Childs, the first musician asked to produce a commissioned piece for the festival under Tim Jackson''s management. On Sunday evening Branford returns to the main stage with his new quartet in a performance guaranteed to bridge whatever gaps exists between traditionalists and more forward thinking jazz fans.

Where Branford has taken a much more universal approach to music, Wynton has preached the orthodoxy of jazz. Wynton has become a strikingly polarizing figure in jazz, due in part to his enormous popular and commercial success, which has lent a certain weight to his staunch advocacy of "jazz correctness." His pronouncements on jazz have drawn much criticism from many quarters, most noticeably in an acrimonious public debate several years ago with pianist Keith Jarrett, who accused Wynton of sacrificing feeling and innovation on the altar of jazz propriety.

"Wynton has been a lightning rod last the last few years, which is a mantle he is willing to accept," says Jackson. "He has opened himself up to being one of the major spokespeople for jazz, and in most camps people give him large amounts of credibility."

Wynton''s confidence and credibility is due in large measure to having single- handedly, some would argue, resurrected jazz from the enervating inertia of jazz fusion and funk.

"In my generation, we didn''t know how to play the blues, couldn''t improvise over chord changes, didn''t know anything about swinging--and didn''t care either," Wynton commented in the liner notes to his Columbia Records recording of jazz standards, Marsalis Standard Time, Vol. 1. "We interpreted all of those musical skills as expressive of a bygone era that had no relevance to us."

Wynton''s early critical and commercial success in the 1980s with a quintet that featured his brother Branford on saxophone, and which was closely modeled on Miles Davis'' classic quintet of the 1960s, re-energized popular appreciation for "traditional" or mainstream jazz and helped pave the way for a host of stellar talents like Joshua Redman, Kenny Garrett, Terence Blanchard and Roy Hargrove. On top of his early recording accomplishments, Wynton went on to win a Pulitzer Prize for his jazz oratorio Blood on the Fields, and land the plumb position of artistic director of jazz at Lincoln Center and conductor of the Lincoln Center Jazz Orchestra.

Saturday night''s mainstage performances will feature Wynton conducting the Lincoln Center Jazz Orchestra in what promises to be a showcase for the kind of marvelously wide-ranging compositional skills and ensemble improvisation that is the hallmark of Marsalis'' style and wide-ranging appreciation for jazz in all its forms. Marsalis will perform as a special guest of the MJF High School All Star Big Band Sunday afternoon, reflecting the role he has taken as a jazz educator. Marsalis returns with the Lincoln Center Jazz Orchestra that evening at Dizzy''s Den.

Despite Branford and Wynton''s joint appearance at the festival, they are not scheduled to perform together over the jazz fest weekend.

The essence of the debate over tradition versus innovation has been most succinctly addressed by two of this country''s most respected music critics, Stanley Crouch, a staunch advocate of Wynton Marsalis'' philosophy who has written extensively about Marsalis and his music, and Gary Giddins, one of the most respected writers on jazz.

In his book,.Visions of Jazz, Giddins pondered the essential question facing the future of jazz into the 21st century by asking whether jazz will be, "...a repertory dominated by the tastes of dilettantes, a morbid obsession with the saintly dead, a horror of innovation?"

For Crouch, the future of jazz comes down to certain basics which are essential to any music choosing to call itself jazz. Also writing in Marsalis'' 1987 Columbia Records recording Marsalis Standard Time, Vol. 1, Crouch states, "...the responsibility passed on to the more ambitious artists of each generation is to learn how to redefine the fundamentals while maintaining the essences that give the art its scope and its grandeur." Crouch goes on to define those essential qualities of jazz as swing, blues feeling and improvisation within an ensemble setting.

By building this year''s festival around the birthday celebrations of Miles and Coltrane, Jackson has struck an appropriate middle ground between innovation and tradition.

"Each year we''re looking at different ideas we can build upon," explains Jackson. "This year''s idea has a lot of historical context because of Miles'' and Coltrane''s [performances] at Monterey. We tried to build some interesting programming around that and not just the standard issue stuff. Both musicians had a huge impact and continue to have a huge influence in terms of the different styles they generated."

"Both went through different periods and phases in their careers," adds Jackson. "You can break down Miles'' career starting with bebop and Charlie Parker, the ''Birth of the Cool'' and larger ensembles, the first quintet with Coltrane and then the second quintet with Wayne Shorter into the electric stuff. In each area he had a huge influence, and you can hear the influence on Wynton in his first quintet.

"With Coltrane you have him coming out of the ''sheets of sound period,'' working in a modal context with Miles, the serious chordal changes in Countdown, and Giant Steps simultaneously, then he moved into the modal arena. You can hear Coltrane in a lot of what Branford does."

This idea of influence and the passing of the musical torch from one generation to the next has often been an uneasy one, one that brings to mind the old Oedipal dilemma of the need to reject the past in order to find a new voice for a new future.

There is no escaping the irony that innovations considered an outrageous violation of tradition by an earlier generation in many cases become the new tradition by a later generation.

When bebop heralded the emergence of a new kind of jazz, trumpeter Louis Armstrong branded the music as "modern malice." Yet trumpeter Dizzy Gillespie, one of the key proponents of bebop along with Parker and Thelonious Monk, acknowledged his debt to Armstrong by stating, "No him no me." Today bebop is considered very much a part of jazz''s mainstream.

Despite Wynton Marsalis'' own enormous debt to Miles Davis, he was unequivocal in his criticism of Miles having embraced electronic music, going so far as to claim that, "Bird [Charlie Parker] would roll over in his grave if he knew what was going on."

From Jackson''s perspective of having overseen the MJF for the past 10 years, he feels the music does seem to be somewhat mired in tradition to the degree that no new artists have broken through with a totally new take on jazz.

"It doesn''t feel like there''s been huge amounts of innovation the last few years," comments Jackson, an accomplished jazz flutist in his own right. "Most artists are redefining the traditions put down before them. They''re putting their own voice to that, but right now we don''t have any major instrumental innovators like Monk, Miles or Coltrane."

When posed with the hypothetical proposition that jazz has nowhere else to go in terms of innovation, Jackson defends the notion that there are always new musical landscapes to explore.

"Human nature always strives to do something new, to go one step beyond," Jackson insists. It''s all very individual. Any great artist pays due respect to the past, which provides the foundation to build on. From there each person finds in their individual soul where they want to go, to try something new or different or a much more subtle variation on theme.

"Great music to me comes down to emotional feeling, not necessarily the notes or sound of the instrument. It has to do with things like phrasing, a general overall feeling or intangibles you can''t point to. A lot of it does point back to the context the artist is working in, and generally you find the best music happens when musicians have worked together a long time, at that point of being able to feel free with the people you''re performing with."

Jackson himself admits to being uncertain how the mix of performers will play out relative to the idea of paying tribute to Miles and Coltrane, but therein lies the magic of the music and the essence of a great jazz festival.

"It''s tough to know until the music happens how these pairings will work," admits Jackson. "There are tremendous possibilities with a lot of these new music collaborations, and that''s what''s fun about a large festival in a live arena. Things will be on the edge a bit musically."