He’s composed some of the largest-scale choral and orchestral movie music of recent years, created the most cutting-edge electronica in modern film and scored some of the most popular animated movies of the past decade.

But, says Harry Gregson-Williams, “I view myself as a musician who has to wear many hats. A musician first of all, a composer second.”

Hollywood could use a little more modesty like Gregson-Williams’. And versatility. Over the next seven weeks, two high-profile summer films will showcase his music: “X-Men Origins: Wolverine,” Fox’s fourth in the mutant-superhero series, opens May 1; and “The Taking of Pelham 1 2 3,” Columbia’s remake of the ’70s subway thriller, is slated for a June 12 debut. In tone and color, they couldn’t be more different.

For “Wolverine,” says the composer, a traditional orchestral score seemed appropriate. “My job is to give the viewer a sense of adventure and, at the same time, never let up a certain amount of tension. Hugh Jackman’s character is always on the edge.”

On “Pelham” — his seventh project with director Tony Scott — the music “must propel us through the story, especially towards the end,” and that required “quite a lot of electronics,” the composer says, although a string orchestra is also featured.

This kind of hybrid score (part orchestral, part studio-created via sophisticated samples and sequencers) has become a Gregson-Williams trademark, especially for contemporary stories — a bit of a surprise to those who know that the composer was a pencil-and-paper musician who had never even used a computer before his arrival in America.

Gregson-Williams has been a musician as long as he can remember. He toured Europe for years as a boy chorister, later studied at London’s Guildhall School of Music and Drama, then spent years teaching music in both England and Africa.

It was composer Hans Zimmer who discovered Gregson-Williams back in the early 1990s. Without knowing it, Gregson-Williams had followed in Zimmer’s footsteps, assisting composers Richard Harvey and Stanley Myers, both old Zimmer colleagues from his London days.

Zimmer enlisted Gregson-Williams to conduct the London choir for his “Crimson Tide” score in 1995, and within a year Zimmer invited the novice composer to join him at his Santa Monica complex, Media Ventures.

“All of us have to start somewhere,” says Gregson-Williams, between sips of tea at his Wavecrest Studios not far from the beach in Venice. “I’d sit at the back of the room, listen carefully and learn the dynamics of what was going on. That was invaluable. Looking back on it, I don’t know how else I would have made a start.”

(Says Zimmer: “He’s the closest thing I have to a little brother. It’s his originality that shines, and his craftsmanship is second to none.”)

From early collaborations — “The Rock” with Zimmer and Nick Glennie-Smith, the animated “Antz” and “Chicken Run” with John Powell, “Enemy of the State” with Trevor Rabin — to solo efforts like the charming “The Borrowers” and the driving “The Replacement Killers,” Gregson-Williams quickly established a reputation for versatility and a tireless work ethic.

The worldwide success of “Shrek” in 2001 helped to catapult Gregson-Williams (and co-composer Powell) into the front ranks, but it was the poundingly effective combination of techno beats, traditional orchestra and ethnic instrumentation of “Spy Game” later that year that made listeners sit up and take notice — and solidified his relationship with director Scott, who subsequently hired him for the propulsive, guitar-flavored “Man on Fire” (and, still later, “Domino” and “Deja Vu”).

The grand-scale Gregson-Williams, however, has attracted the most attention of late: Golden Globe and Grammy nominations for “The Chronicles of Narnia: The Lion, the Witch and the Wardrobe,” the C.S. Lewis fantasy that demanded a sweeping, romantic score; Ridley Scott’s medieval epic “Kingdom of Heaven,” which required Latin choruses, ancient instruments and Middle Eastern colors; and last year’s “Narnia” sequel “Prince Caspian.”

Regardless of scale, Gregson-Williams says the start of each project is always the same: “My approach is quite intuitive. It’s necessary to uncover the emotional beat, the raison d’etre for this film to exist in the first place, and thereby try to burrow into its psyche musically.”

And, he adds, “I spend some time putting together a kind of sonic spectrum. If there is going to be something other than acoustic instruments, anything generated from my machines, I’ll assemble an artillery of colors and rhythms. All these things need to come together.”

More than 50 projects (films, TV, commercials, videogames) later, Gregson-Williams remains fascinated by “the extraordinary capacity for music to bring another dimension, impact, to the film. Not just any piece of music, but a piece of music being played at that speed, and that pitch, with that amount of delicacy, at that precise moment.”

Yet he seems to take equal pride in another, unseen, part of his career: training the next generation of film composers, just as Zimmer had mentored him. Past assistants have already succeeded on their own, among them Steve Jablonsky (“Transformers”), Stephen Barton (“Mrs. Palfrey at the Claremont”), Toby Chu (“The Riches”) and current assistant David Buckley (“The Forbidden Kingdom”).

“I think what goes around comes around,” says Gregson-Williams. “I know, from my own personal journey, there has got to be help to get onto the next stage. And it’s an extremely healthy way for the film music community to nurture its own.”