Glass is busting out all over.

Since his opera "Einstein on the Beach" in 1976, Philip Glass's name has been one to reckon with on the operatic scene, as the public has followed him into the world of minimalism and beyond. With productions escalating in increasingly prominent opera houses, Glass's music has been greeted with reactions that have ranged from rejection to growing waves of adulation. People see Glass as either a hero or enemy of music.Though opera is a somewhat rarified field of endeavor, Philip Glass is no ivory tower composer, concocting musical theorems with his head in the clouds. Indeed, he is a crossover artist, almost as popular in pop and rock circles, who does orchestral works as well.

For him, music exists between a composer and a listener, and he's discontent that people in small cities and hometowns can't see his work.

Accordingly, he'll play Salt Lake City Monday night with "1,000 Airplanes on the Roof" - one stop in what another generation would have called a barnstorming tour, taking his inimitable style directly to the grass roots in some 40 cities. The show will conclude its run in New York's Beacon Theater, Dec. 15-20.

The performance is in Kingsbury Hall at 8 p.m., and tickets at $17.50 and $13.50 are available there, at Cosmic Aeroplane, Smokey's or Smith'sTix.

"1,000 Airplanes" had its world premiere last July in a hangar at the Vienna International Airport. It is a 90-minute "science fiction music-drama" for a speaking actor and small ensemble of synthesizers, amplified winds and wordless soprano voice.

The libretto devised by Chinese-American playwright David Henry Hwang (this year's Tony winner for "M. Butterfly"), deals with a main character, M., who has an extraterrestrial experience, but can't talk about it for fear people will think he's crazy. He experiences disorientation, confusion and flashes of revelation.

Completing the distinguished artistic troika responsible for "1,000 Airplanes," Jerome Sirlin has staged the work in a three-dimensional dreamscape of holographic projections, using nine projectors to create images of cinematic illusion. The production has been described by critics as "a knockout," "the best use of visuals I have seen in theater," "wild and weirdly funny . . . visually spectacular," "a beautiful and touching contemporary fable."

(Of course, too, the L.A. Times' churlish Martin Bernheimer calls it a "super-trendy, hyper-pretentious, multimedial, neo-minimalist, science-fictitious, deja-vu, deja-entendu, quasi-music drama," so it's not everyone's cup of tea.)

The minimalist movement emerged during the 1960s as a reaction to the dry, cerebral music of mid-century. Instead of brainily constructed tone rows as building blocks, one began to hear little motives, often just four or five notes, even the outline of a chord, reiterated at length in varying rhythms, transpositions and sequences. Though composers have worked according to their own inclinations, the net result seems to be a return to comprehensiveness, to lyricism and melody.

But Glass has sprinted out beyond the pack, into territory of his own. "Minimalism was over for me by 1974," he has said.

In declaring him Musician of the Year in 1985, Musical America commented on "the heady, euphoric quality of his music, its originality, driving beat, sense of drama, aura of mysticism, and its sheer magnitude. . . . Whether you hear fascinating rhythmic structures or maddening repetition, Hanon exercises or a tour de force emotional aria depends upon your identification."

Consider the following Glassiana (only a few items from a prolific output and dizzying schedule):

His opera "Akhnaten," which deals with a renegade pharaoh who may have been the first monotheist, premiered in Stuttgart, has played the New York City Opera and London's National English Opera. "Satyagraha," about Gandhi's early years, sold out seven performances in Chicago, was a big success in Seattle, and is scheduled next spring by San Francisco Opera. His "Fall of the House of Usher" premiered in May in Cambridge, then moved to the Kentucky Opera; "Einstein on the Beach" was just produced in Stuttgart. His "Palace of the Arabian Nights" with Robert Wilson is scheduled for Paris in late 1989.

And most prestigious of all, the Metropolitan Opera has awarded Glass a $325,000 commission, the highest ever for an opera, to create a work for October 1992, the 500th anniversary of the discovery of America. He plans a three-act allegory titled "The Voyage."

A few weeks ago, Glass visited Utah to explain his motivations for this tour. In person he is a pleasant surprise, the most approachable of people, more comfortable to chat with than most of your neighbors. His direct blue eyes engage yours with friendly intensity, he cares about your thoughts, and attaches his onto them, to form a fluid chain of vivacious conversation.

"We have built a piece that will travel, and we are taking it out in person. Not putting it on television, that is a compromise medium," he said. "I am committed to doing theater live, and I think an audience is ready for us in the small cities of America. We have to go out and find it. I expect this tour to be a lot of fun, going to places where no one has seen my work, and seeing audience reaction when they encounter it for the first time."

Politics, religion, science, philosophy, psychology? Are those the stuff of great music theater?

Glass thinks one reason why he's successful is because he writes about the subjects that people think about. "I talked to Doris Lessing, whose novel I used for `The Making of the Representative for Planet 8' (Houston, July 1988), which is about death, dying and escape from a sudden onslaught of an ice age," he said. "She said, `That's the sort of threat that ordinary people are concerned with right now."'

Which suits Glass just fine, since he's not interested in writing "romances." "I want social, human subjects," he said. Indeed, he feels himself a part of a community of theater that is geared to deal with these very subjects meaningfully.

"1,000 Airplanes' is about communication," he explained.

While the work has certain Spielberg connotations, it's quite different, said Glass. The extraterrestrials in "1,000 Airplanes" are not cute and warm; they are threatening and frightening, and better off forgotten.

"Lots of people have had extraterrestrial experiences," he said. "Think of the innumerable sightings that people have reported. Europeans may say they don't have them, but they surely have cropped up there, and in India and Asia. We may be tapping popular mythology or fantasy here.

"We know that serious science is trying to pick up signals from outer space. At the very least, communication with aliens is a preoccupation.

"We come very close to staging an encounter at one point. This is accomplished by projections on a series of screens that pick up images and have varying densities as they disappear at the back of the stage. With lighting from the side we get a three-dimensional effect."

Sometimes the actor sits with the musicians of the ensemble, or reacts on one of several levels. "The central character can be a man or a woman, we alternate in long runs," he said. "And it's surprising how different the experience becomes according to the male or female persona, though all other elements remain the same."

Glass has greatly enjoyed what he considers a lucky collaboration with Sirlin and Hwang, but he doesn't expect to ever work with the two together again, though he may work with one or the other. "We might fall into a formula," he said.

Glass broke out of the mold when he was in his late 20s. Before that, he led the life of a conventionally trained modern musician, complete with Juilliard education. "I composed like my teachers; Persechetti and Milhaud were my idols," he said. "Until my mid-20s I lived on prize money, which financed my work with Nadia Boulanger in Paris. But at 28, when I asserted my individuality, no more prize money."

In Paris Glass did encounter the raga music of Ravi Shankar, which had a profound influence, especially the rhythms. He also studied with Ala Rahka, Shankar's tabla player.

"I came to feel that my teachers had wandered away from writing for a public, for Real people," said Glass. "Yet I didn't want to just do film scores. (Though he has done so very successfully - notably "Koyaanisqatsi" and "Powaqqatsi.") I still had values."

It was perhaps inevitable that Glass should find his way into opera, the medium in which he essentially enjoys most to compose. "Music theater is the workplace where dance, music and imagery come together," he said.

"I like to bring music to people with the greatest possible reality, since we exist most essentially in what we say to each other. No one is really ever alone; at our most solitary, our heads are full of thoughts of others."

"Satyagraha" is an example of riding the crest of a wave of popular thought. "I was very lucky that it came out just before the big movie about Gandhi," he said. "I had no way of knowing there would be a movie, and it would be so popular, but it helped my piece immeasurably."

Perhaps that's a major element in Glass's success. "I do what interests me," he said, and he may just be so well in touch with his times that he hits upon what interests other people, too - a happy faculty that meaningful opera composers of every era have had.