Few jazz musicians have garnered more widespread recognition or explored more diverse musical terrain than Pat Metheny, whose brilliant 1976 debut trio recording, Bright Size Life, heralded the emergence of one of contemporary jazz''s most gifted composers and instrumentalists.

As leader of the eponymous Pat Metheny Group, and collaborator with such diverse musicians as Gary Burton, Charlie Haden, Joshua and Dewey Redman, Derek Bailey, Bruce Hornsby and Joni Mitchell, Metheny has reconfigured the entire spectrum of American musical styles--from mainstream and experimental jazz, to blues, folk, pop and rock ''n'' roll--through a sensibility that is populist in appeal while remaining faithful to the essence of improvisational music.

With Sunday evening''s debut of the Pat Metheny Trio, fans will have a rare opportunity to hear Metheny perform within a musical context that provides the best showcase and expression of Metheny''s songwriting and instrumental gifts--his purity of tone and phrasing, his instinctive feel for melody within an improvisational context, and that haunting mix of romantic exuberance and wistful lyricism that seems to evoke the promise, hopes and dreams of the American spirit.

In an exclusive interview with Coast Weekly, Metheny discussed his upcoming debut at the Monterey Jazz Festival, the significance of the trio setting to the development of his music, and the highlights and influences on a career that remains as vital and creative as ever.

"I''ve always wanted to play the Monterey Jazz Festival, and this year they sent the invite early, so I put this trio together specifically for the festival," says Metheny, whose longstanding invitation to perform at the MJF has been blocked both by scheduling conflicts, and, according to MJF Director Tim Jackson, the difficulties of accommodating the elaborate set-up of the Pat Metheny Group.

"Over the years I''ve done a bunch of trio recordings, and that playing and that environment of music is the one I''ve played the longest. It''s a real familiar setting," says Metheny.

In comparison to other musical contexts, Metheny says the trio setting provides a unique set of challenges and opportunities that are often missing from other group configurations.

"Each setting asks a different question and you have to come up with the right answer," says Metheny. "The trio setting role is different, and with the trio setting, there is space for other things to happen with the guitar. The other players always affect the sound by what their strengths are, what sounds good and what mix of tunes three guys can make to come up with the best sound."

Joining Metheny for Sunday night''s performance on the Jimmy Lyons Stage are drummer Brian Blade, who played with Metheny on saxophonist Kenny Garrett''s tribute album to John Coltrane, Pursuance, and San Francisco Bay area bass player Larry Grenadier, who plays with saxophonist Joshua Redman and whom Metheny regards as, "...one of the two or three best new bass players."

Although Sunday''s appearance will only be the third for the trio--following two sold-out performances at the Kuumbwa Jazz Center in Santa Cruz--Metheny was enthusiastic about the band''s potential to create some exciting, and unpredictable music.

"The thing that''s great about Brian and Larry is they''re the kind of musicians with no stylistic bias," says Metheny. "There''s that common link between us of openness, and there''s no question the sound and music will be great. I don''t know yet what the song selection will be."

Regardless of the style or musical format, Metheny''s abiding love of melody is the essence of his music. Whether he''s tearing through one of Ornette Coleman''s oblique free-jazz masterpieces or playing one of his own straight-ahead, pop-inflected tunes, Metheny''s gift for melody, even within the context of pure improvisation, accounts for his broad appeal as both a recording and performing musician.

"What makes music good music is melody on top. And when I say melody, I mean it in the broadest sense in terms of equlibrium: a resonance and architecture of music," explains Metheny. "My favorite players were melody guys like [John] Coltrane, [Stan] Getz, [Gary] Burton, and Herbie [Hancock], all incredible melody players."

As far as Metheny is concerned, many of today''s jazz musicians have foresaken melody in favor of music that emphasizes style over substance.

"I think jazz just got away from song and melody," comments Metheny. "After me, melody was not an issue to people, and almost all the younger guys are not good in [that area]. It''s now more about style, and politics and other stuff far away from the kind of values that, to me, are essential."

As a musician who has played with a host of acknowledged jazz greats like Sonny Rollins, Roy Haynes, Herbie Hancock and Ornette Coleman, Metheny remains a major exponent and advocate of jazz music''s tradition of being a cross-generational art form. His appearance on Sunday with Blade and Grenadier is very much a part of that tradition, one that has been important in Metheny''s own career and which is very much a part of the philosophy behind the Monterey Jazz Festival itself.

"That''s a true tradition that''s gone on from the very beginning, with information getting passed through that experience," Metheny acknowledges. "That''s a very important part of my story. I''ve always been around older musicians who were teachers for me, but oddly I''m finding myself on the other side of the fence," Metheny adds with a laugh.

"Every one of us are beneficiaries of those experiences, and good musicians have that quality where it doesn''t matter who you''re playing with. The only time it matters is in terms of whatever led up to it and what it is to tell your story."

When asked to look back at the highlights of a musical career that shows no sign of creative inertia, Metheny reserves his greatest affection for the ongoing musical journey with the Pat Metheny Group, as well as his longtime collaboration with pianist Lyle Mays.

"It''s such a trip to play in a band that covers so much sound, stylistically," says Metheny, "the open-endedness of the Pat Metheny Group, and the incredible range of potentials it offers sonically. We have seen and witnessed each other going through millions of life changes, and that informs everything.

"My ongoing collaboration with Lyle [Mays] sits at the top of the list," adds Metheny. "It''s almost taken for granted, but he is one of the most exceptional musicians that''s been around."

For a musician who once regarded himself as a purist and "jazz snob," it is ironic that Metheny has perhaps done more than any other musician of his generation to push the boundaries of jazz, to embrace both a wide range of musical influences and new technologies in his music.

"As a guitar player, I''ve always had problems with the traditional jazz guitar, mostly in the area of sound," explains Metheny. "The general sound didn''t have enough color to it, and a lot of my research was into trying to come up with ways of getting a variety of sounds happening, but all from the same point of view.

"The technology that has emerged has been a partner for me to utilize, and sometimes the advances have been amazing. I''ll never forget the first time I picked up a Roland guitar synthesizer, I had a heart attack," recalls Metheny. "The sound had a real power and carried weight and information. It was an aphrodisiac for creativity and it was so stimulating I wrote 10 songs.

"As a composer, the technology has been even more dramatic--the whole thing of being able to write music instantly and hear a demo," adds Metheny. "It''s been stimulating to come up with music I wouldn''t have come up with without access to those tools, but I was never interested in change for the sake of change. I just tried to let my philosophy as a musician determine the sound."

Over the next several months, Metheny''s unique sound will be popping up on a host of new recordings, including a just-completed duet album with [guitarist] Jim Hall, a seminal figure, along with Wes Montgomery, in Metheny''s development as a guitarist; a quartet recording led by saxophonist Dave Liebman, and his fifth collaboration with vibist Gary Burton, all of which Metheny says remains the essence of his journey as a musician.

"I''ve been lucky to do so many kinds of things, and that balance has been important for me, to try to have an output of records and gigs to reflect those different interests as a musician," says Metheny.

"I can play a lot better now than I used to, and when I first started making records, I had only played for five years. Now I''ve played for 30 years, and that helps me get around the instrument and not worry about things. I can get right to it and a certain depth is there now and is more natural to me as I get older." cw