A theme emerges

The conductor, standing on the stage, waves his arms, and music fills Symphony Hall. The composer, a slim man in black jeans and a dark coat, listens from the balcony. He doesn't interrupt or change his expression with each new movement. His only response is to occasionally look up from the score resting in his lap and glance down at the players.

Inside, though, relief washes over Michael Gandolfi like the warm string chord that opens his piece, ''Impressions From 'The Garden of Cosmic Speculation.' " Last summer, at the Tanglewood Music Center, the first rehearsal left him crushed -- he called his wife, Maria Martiniello, to tell her he had failed, that this piece would never work. ''Impressions" did come together, but only after more rehearsals. And the 20-minute work scored a coveted slot in the Boston Symphony Orchestra's subscription series -- a rare honor for a living composer, particularly one who is not yet 50.

Within minutes of the beginning of the BSO rehearsal this week, Gandolfi realized he was in good hands.

''It blew me away," he tells David Zinman, the BSO's guest conductor, backstage after the run-through. ''I can't believe they're going through it for the first time."

For the composer, the excitement comes largely in hearing his piece played by one of the finest orchestras in the world. He knows that tonight -- and in concerts tomorrow, Saturday, and Tuesday -- the Italian kid from Melrose is going to hear his creation on the big stage.

Not that Gandolfi is about to toast his success. That would be self-promotion, which makes him uncomfortable. He won't even consider what the concerts might do for his career. He says he writes music for the same reason all composers do.

''We do this because we truly have a passion for it," he says. ''The career side of it is very difficult to control. I can only control what I write."

This is how Gandolfi confronts success. It is the same way others might deal with artistic anonymity. He speaks of his love of music, his admiration for certain composers, and his desire to keep working.

Getting out the word is left to his wife, Martiniello, a graduate student at Harvard's School of Education. Knowing her husband wasn't about to make a big deal about the week, Martiniello found herself badgering him for e-mail addresses so she could let friends know about the BSO concerts. When New England Conservatory, where he teaches composition, wanted to host a preconcert reception, Gandolfi felt awkward. Are you kidding, she told him. In the end, Martiniello helped talk Gandolfi through the list of potential invitees.

''When he needs to lecture and talk to people about conceptually what the work is about and technically what it implies, he's fine," says Martiniello. ''But in terms of talking about himself and how good he is, you won't hear him."

Cosmic convergence
Gandolfi, who lives in Cambridge, first learned about the Garden of Cosmic Speculation in the gym. On the treadmill, thumbing through Harvard Magazine, Gandolfi read about Charles Jencks, the architect who had created the 30-acre garden in Scotland and published a book on its features.

The garden melds nature and science, part of an ongoing project by Jencks to incorporate the often abstract questions and principles of physics into a living landscape. There are Dadaist sculptures on the grounds, fences meant to simulate energy waves, and a house-like object called ''The Nonsense."

For Gandolfi, an avid reader who has long been fascinated with the physics of everyday existence, the elements of the garden were intriguing. He went about setting them to music.

The first of four movements in ''Impressions" is called ''Introduction: the Zeroroom." It's a slow, swirling opening named after the surreal entry hall that leads to the garden. The final movement, ''The Nonsense," is a whimsical, energetic section meant to play off of the angular and nonsensical object that sits within the garden.

As deliberate as Gandolfi's creation might sound on paper, the music doesn't come across as cold or calculated. It is romantic music, says Osvaldo Golijov, a friend and contemporary composer whose own work has been performed by the BSO.

''That's the difference between Mike and the others," says Golijov. ''For instance, you have Milton Babbitt, who is very complex and transparent at the same time, but at least to me he does nothing to engage me on a sensual level. In Mike's music, the opening harmonies of the piece are simply beautiful for anybody. You don't have to have a PhD in music. You are just struck by the pure beauty of the chords."

Rock boy
Gandolfi, 48, was a late bloomer as a classical composer. Though he grew up around Bach and Beethoven -- his two older sisters would become professional pianists -- Gandolfi preferred rock as a kid. He grew up in Melrose before moving to Reading at the age of 12. His parents were first-generation Americans, born to immigrants from Sicily. His father, Joseph, worked in the North End at a shellfish wholesaler.

In those days, his sisters, Connie and Jodi, would go with their piano teacher to Symphony Hall every week. Michael stayed home, teaching himself the chords to Led Zeppelin and Beatles songs on his guitar.

''We tried to get him interested in classical music," says Jodi, who lives in San Francisco. ''The funny thing is he never said he wasn't interested. He just took no steps of his own and kept on doing what he was doing -- playing his electric guitar in the garage."

It was after his sisters went off to college that Gandolfi, now in high school, began branching out. He heard jazz for the first time, feasting on John Coltrane and Herbie Hancock records. He also began listening to the 20th-century modernists Bartok and Stravinsky.

''If I had heard that when I was 8 years old, I would have fallen in love with it," Gandolfi says today. ''My sisters were playing Beethoven, Bach, Haydn."

Gandolfi enrolled at Berklee College of Music but eventually transferred to NEC. Around that time, Jodi Gandolfi, studying piano in Germany, received a tape in the mail from her brother.

''It was the first piece I had ever heard from him, and it just took my breath away," she says. ''It was a gorgeous piece he wrote for two pianos and percussion. It was at this point that I realized, my goodness, he's a real composer."

The real thing
The BSO discovered that Gandolfi was a real composer a few years later. His earliest works date to the late '60s, but his first commissions didn't roll in until the early 1980s. His work has been performed by Boston Musica Viva, the San Francisco Symphony, Shakespeare & Company, and his native town's Melrose Symphony Orchestra. The BSO actually played one of his earlier compositions, ''Points of Departure," in 1998, though its scoring is for chamber orchestra, in this case 26 players.

''Impressions" emerged out of a commission from the Tanglewood Music Center. It was conducted there last summer by Atlanta Symphony Orchestra music director Robert Spano.

''His music is very rhythmic, quite direct in its language," says BSO artistic administrator Tony Fogg. ''He's got a great sense of humor, and this piece is full of pictorial images."

Fogg asked Zinman, this week's guest conductor, if he would be interested in playing Gandolfi's piece. Though Zinman hadn't heard ''Impressions," he was impressed with some of Gandolfi's other works.

''I said, 'This is a guy with talent,' " says Zinman, music director of the Aspen Music Festival and School. ''I'm sure he'll write a good piece."

After the rehearsal this week, Zinman says he would consider playing ''Impressions" when he conducts in other places, most likely in Aspen.

''It has communication power -- one is carried into the argument from beginning to end," Zinman says. ''One doesn't zizz out at all. It's beautiful in places, it's stringent where it needs to be, but it's a piece that I would say continues the line of music into the 21st century."

For Gandolfi, the BSO concerts won't mark the end of ''Impressions." He plans to write more movements, perhaps as many as 15 in total. Jencks, who heard about the work, sent an e-mail inviting Gandolfi to visit the garden. The composer intends to later this year.

''I'm humbled," Gandolfi says about the BSO program, which also includes the works of Bartok and Mussorgsky. ''But I'm not feeling like, OK, I've hit the summit. I feel like I'm barely clawing my way up."

Geoff Edgers can be reached at gedgers@globe.com.

The Boston Symphony Orchestra, conducted by David Zinman, performs Gandolfi, Bartok, and Mussorgsky at Symphony Hall tonight, tomorrow, Saturday, and Tuesday at 8 p.m.