I'm not ordinarily squeamish about loud music, but Spy vs. Spy's opening downbeat was so brutal that I thought I felt my eardrums break. Thirty seconds into the first tune my head was spinning as though I had been drunk and awake for days on end, and my stomach began to churn in response to the music's velocity, which I decided was almost as senseless as the volume. Zorn and Spy vs. Spy--the alto saxophonist Tim Berne, the bassist Mark Dresser, and the drummers Joey Baron and Michael Vatcher--were grinding Coleman's music down into a feelingless, monochromatic din. They treated his compositions, which are benchmarks of free jazz, as though they were speed metal (bohemianized heavy metal, without the oversize stage accouterments) or hard core (the most dystopian contemporary mutation of what used to be called punk). Although intended as homage, the concert amounted to heresy, presenting Ornette Coleman without the swing, sensuality, and blues-based joie de vivre that make even his own forays into rock and funk recognizable as jazz and identifiable as his.

All around me people were fleeing with hands over their ears, while a handful of mostly younger audience members, there for the duration, sneered at them. I should have fled too, but a combination of shell shock and journalistic instinct kept me glued to my seat. (Someone, maybe an infuriated Ornette Coleman fan, overturned a sales table of Zorn albums and compact discs on his way out.) Who would have thought that a quintet without a single electric instrument could inflict such pain? As though to add insult to injury the band members chatted among themselves between salvos but didn't address the audience until about twenty minutes and nine or ten numbers had passed. When Baron glanced up from his drums, rather dazed-looking himself, I thought, and asked, "How ya doin' out there?" I didn't hear anybody answer him.

This nightmare was still on my mind when I spoke with Zorn in New York last spring. "A lot of people were outraged when they first heard Ornette play his music in the fifties and sixties," he said, in defense of his similar junking of Coleman on his 1989 album Spy vs. Spy (Elektra Musician 9 60844). "The speed and the power and the volume, those are elements that admittedly were not part of Ornette's original conception. But those are essential elements in bringing it up to date, in giving it the same impact it had then. Volume is an important parameter. It's visceral. Physical."

Granted, with practically anything now permissible in music, the threat of physical damage posed by unreasonable volume might be the last remaining shock. But shouldn't a musician be wary of long-term effects on his own hearing? "Forget about it," said Zorn, a mild-looking thirty-seven-year-old native New Yorker with a long, narrow face, stylish eyeglasses, and, when I saw him, the beginnings of a ponytail.

"My ears are blown already. I've been playing loud music for a long time." But he admitted that some of his sidemen wear earplugs. "That's the loudest situation they've ever been in," he said, referring to Naked City, another of his bands, which, in addition to jazz tunes and movie themes, plays old surfing hits and Zorn's own hard-core originals--a repertoire for which, I told him, top volume does seem appropriate. When I heard Naked City perform live, they were less painfully noisy than Spy vs. Spy.

That observation brought a hoot. "We probably weren't loud enough, then," Zorn said.

BY Zorn's current standards, probably not. One of those New Yorkers who gives the impression of being as proud of his city's sleaze as Iowans are of their corn, Zorn delights in his self-created role as the bad boy of Manhattan's eclectic fringe music scene. By now it's part of the identity he brings onstage with him.

In 1989, when the Brooklyn Philharmonic performed his "For Your Eyes Only" as part of New Music America, an annual showcase for avant-garde music which is staged in a different city each year, he used the space allotted him in the festival brochure for a biography to attack NMA for annually sponsoring the big names who "look good on grant applications or concert posters." (Most reviewers lambasted Zorn for taking the money if he felt that way, but his piece had been commissioned by the Brooklyn Philharmonic, which considered the piece its own to perform whenever it wished.)

Zorn once wrote a piece for the Kronos Quartet which called on the members of that resolutely with-it but essentially straitlaced string ensemble to bark and growl like dogs. That's an example of his humor at its most lighthearted, but it can be heavy-handed, too. He once faxed a message to an Austrian concert promoter requesting that his trio be billed as ZOG--an acronym for "Zionist-occupied government," which is a rallying cry for The Order, the Aryan supremacist group that murdered the Denver talk-show host Alan Berg in 1984. The trio, which Zorn describes as "the world's first all-Jewish heavy-metal band" and whose other members are the guitarist Elliott Sharp, a veteran free improviser, and the drummer Ted Epstein, from Blind Idiot God, Zorn's favorite speed-metal group, ultimately decided on the name Slan, after a monster in a 1950s science-fiction novel.

Zorn, in short, is exactly the sort of rude, overgrown adolescent you would go out of your way to avoid, if only he weren't so . . . well, interesting, important, and influential (at least potentially). A decade ago he seemed just a minor figure in the New York avant-garde--not innovative, just eccentric. At that time his work consisted mostly of "games" pieces, which were prankish, discontinuous, Zorn-"cued" group improvisations with titles like "Archery," "Rugby," and "Soccer." These sounded like frat-house Stockhausen and qualified as Zorn compositions only in the sense that a party can be said to belong to the person who throws it.

Then Zorn sprang a delightful surprise with The Big Gundown (Nonesuch 9 79139), a 1986 album on which he played the film music of Ennio Morricone, an Italian composer best known in this country for his soundtracks to Sergio Leone's spaghetti westerns. But Morricone has a much greater range than that, as Zorn showed. The album would have been notable if only for rounding up a who's who of lower-Manhattan music, including the keyboard player Wayne Horvitz and the guitarists Bill Frisell and Fred Frith, all of whom subsequently joined Naked City. With its kinesthetic mix of musical styles and its equivalent of jump cuts, wipes, fades, and dissolves, it played like a witty essay on the relationship between music and film--the perfect salute to its subject. In an obvious parallel with contemporary painting, the album established Zorn as a composer by acquisition, capable of altering a work's meaning by shifting its context. He gave new significance to the word "cover," traditional record-business parlance for slavish emulation of another artist in an attempt to tap a new audience (in the 1950s, for instance, Pat Boone and other white artists "covered" Fats Domino and Little Richard). In Zorn's terms, reinterpretation in another style is the ultimate act of homage.

A year later he followed up with Spillane (Nonesuch 9 79172), an album whose lengthy title track so successfully evoked the testosterone-and-bile ethos of its pulp-novelist namesake that, as Zorn complained to me, it was accepted as another of his covers rather than as an original work. With these back-to-back releases, Zorn helped to clarify a previously murky new aesthetic: "avant-garde" as an attitude toward music, and an eclectic, self-contained genre, rather than simply a vanguard movement in classical, jazz, or pop music.

ZORN called attention to an audience whose values were identical to his as a performer, and that had just been waiting for someone like him to come along--something usually true of only the biggest pop stars, and almost never true of avant-gardists. "In general, my generation and younger, this is how we grew up," Zorn, who was born in Manhattan and raised in Queens, told me. "We had an unprecedented variety of music available to us, because of the availability of everything on LP."

Zorn's mother, a professor of education, liked classical music and world ethnic recordings; his father, a hairdresser, listened to jazz, country, and French chansons. "And through my brother, who's seven years older and wanted to be a greaser in the fifties, I was exposed to doo wop and the Silhouettes, groups like that." Around the age of fourteen, Zorn says, he immersed himself in Stravinsky, Webern, Ives, Varese, and such contemporary experimental composers as Stockhausen and Mauricio Kagel. "But all through that period I was listening to the Doors and playing bass in a surf band." As a high school student commuting daily from Queens to Manhattan, he also spent a lot of time in Manhattan's repertory movie houses, sometimes watching movies for so long that he had to sleep at a schoolmate's apartment in Manhattan.

He found himself spellbound by film music--"the many styles a film composer has to know in order to complement the images," he says. "In that sense I think the great film composers are the precursors of what my generation is doing today. His pantheon includes Morricone, Bernard Herrmann, John Barry, Dmitri Tiomkin, Jerry Goldsmith, and Henry Mancini. Zorn's biggest formative influence of all, though, was Carl Stalling, whose music for Warner Bros. cartoons he worshiped, he realized later, for its discontinuity and use of Stockhausen-like "sound blocks."

Stalling is suddenly in vogue. Last fall, in New York, Bugs on Broadway featured Bugs Bunny cartoons accompanied by a live orchestra playing Stalling's original music. The best of his sound tracks for Bugs, Daffy Duck, Road Runner, and others in the animated menagerie have now been collected on The Carl Stalling Project: Music From Warner Bros. Cartoons 1936-1958 (Warner Bros. 976027). Zorn, in the liner notes, praises Stalling for "following the visual logic of screen action rather than the traditional rules of musical form," thus creating "a radical compositional arc unprecedented in the history of music."

After high school Zorn briefly attended Webster College, in St. Louis. "a very small hippie liberal-arts school that let you study whatever you wanted to and was the only college that would accept me." It was there that he "got turned on to the jazz scene seriously," through live exposure to Julius Hemphill, Oliver Lake, Hamiet Bluiett, and other then-local musicians who had bonded into a collective called BAG, for Black Artists Group. "I knew I didn't have a place in that, but I didn't really want a place. Jazz was just another kind of music I studied and learned from."

When trying his hand at straight jazz, Zorn can be controversial without any effort. On News for Lulu (Hat Art 6005), a 1987 trio session with Frisell on guitar and the trombonist George Lewis, Zorn plays compositions by Sonny Clark, Kenny Dorham, Hank Mobley, and Freddie Redd--unsung jazzmen associated with Blue Note Records in the late fifties and early sixties, a period and a sound now being driven into the dust by solemn young neoclassical hard-boppers. Zorn's approach is the antithesis of theirs. To begin with, his instrumentation is unorthodox (no rhythm section), and his choice of tunes is noncanonic. And instead of merely zipping through the chord changes of the tunes, he pays careful attention to their melodies and rhythms, finding in them improvisational possibilities that even their composers overlooked.

Not everyone appreciates Zorn's fresh slant on hard bop. Some reviewers dismiss it as his desperate attempt to mask his lack of conventional musicianship. Such criticism irks Zorn, although he swears it doesn't. "Some people say I can't play the changes, some people say I can't play in tune, and some people say I can't play the saxophone," he told me. "My basic response is I'm doing the best I can. You can spend your whole life, like Frisell has, learning to get inside the chords. I don't do it that way."

ZORN'S way still includes free improvisation. Last May he gave a three-night retrospective of his games pieces--each involving a different group of improvisers--at the Knitting Factory, in lower Manhattan, a few blocks from his apartment. I was in the audience the first night, sitting behind two musicians awaiting their turn to go onstage. "Which piece is this?" one asked the other during Zorn's "Rugby." "I don't know. Don't they all sound alike?" the second musician replied. I had the feeling that they'd had this conversation many times before.

A truism about free improvisation is that it's fun to play but murder to sit through. Another truism is that you have to be there: it doesn't work on disc. At the Knitting Factory the rowdy fraternity of Zorn's music won me over, especially the trio piece "Rugby," performed by the cellist Tom Cora and the violinist Polly Bradford, with Zorn on saxophone and duck calls. (Apparently more considerate of audiences on his home turf than of those on the road, he warned that "Rugby" would be "excruciatingly loud," though it really wasn't.) But I hesitate to recommend even Cobra (Hat Art 2-6040), arguably Zorn's most successful record in this genre, which I listened to immediately upon receiving it in 1987 and have had no interest in playing since.

Along with The Big Gundown and Spillane, the best introduction to Zorn's work is Naked City (Elektra/ Nonesuch 9 79238), on which he takes genre-bending to delicious new extremes. Zorn being Zorn, Naked City tries your patience with a cluster of eight ear-numbing rants by the band and the screaming singer Yamatsuka Eye, none lasting more than thirty-eight seconds. My advice is to skip selections ten through seventeen when programming the CD, because the other eighteen tracks justify the effort. Zorn atones for Spy vs. Spy with a crafty reinterpretation of Ornette Coleman's "Lonely Woman," loaded with verbatim Coleman quotes over a this-means-business bass line appropriated from John Barry's "The James Bond Theme" (which is itself transformed into a Jimi Hendrix-style rave-up a few tracks later). It shouldn't work, but it does. The most satisfying of the disc's several movie themes are Georges Delerue's "Contempt" (done as an art-rock symphony, a la Glenn Branca) and Morricone's "The Sicilian Clan," on which Zorn's improvisation takes the form of an edgy but wonderfully apposite countermelody.

Of the Zorn originals, the one that stays with you the longest is "Saigon Pickup." It's just under five minutes long, and it comes at you in sections (as Fred Astaire said of a femme fatale in the Mickey Spillane parody in the movie The Bandwagon): a minimalistic, almost Philip Glass-like piano theme; then Zorn squalling over an Asian-sounding scale; then a country-and-western pastiche; then back to the piano theme, this time reinforced by string synthesizer; then more squalling, followed by more C&W; then some lounge jazz; then some psychedelic organ and reggae drumming; then a gleeful, Ornette Coleman-like melody; then more country, more squalling, more minimalism, and the final fade. Yet it isn't a hopeless audio collage. You never feel as though you're being given a smug demonstration of what's currently hot in music, as you sometimes do with Zorn (on this album's "Graveyard Shift," for example).

Zorn's breadth is such that he tends to fragment the intrepid audience he already has, which would seem to put mass-cult adulation out of the question. But on tracks like Naked City's "Latin Quarter," "Reanimator," and "Batman" (a Zorn original, not Prince's movie or Neal Hefti's TV-show theme) the group rocks out so hard that some of his fans have begun to think of it as Zorn's "boogie" band--his ticket to commercial success. Guess again. Naked City's second release, due later this year, will consist of what Zorn calls "classical covers" of works by Debussy, Ives, and Scriabin, among others. It's all part of Zorn's determination to take listeners by surprise. Let's hope this one doesn't hurt.