Outside, sorority sisters and fraternity brothers in neon-lettered T-shirts walk hand in hand past campus police officers. Inside, just a block away from the University of Southern California’s “Frat Row,” 22-year-old Tim Callobre is intently focused on his music. No Top 40 or bumping DJ beats here; Callobre’s music has landed him performances at the White House and Carnegie Hall. It’s classical stuff. High-minded to the T.

Often called a prodigy, Callobre is a big deal in the classical guitar world. His specialty is improvisational music, which means he knows chord progressions like the back of his hand and can be let loose to produce magic with the snap of a finger. He’s won his fair share of first-place prizes in national and international competitions. The winner of two Young Composer Awards from the American Society of Composers, Authors and Publishers, he was selected for an elite Los Angeles Philharmonic composition fellowship; you might have caught his tunes on NPR. Currently holding a coveted spot at USC’s illustrious Thornton School of Music, Callobre sits in an enviable spot. He’s already got — perhaps inevitable in LA — a feature-length credit and dozens of short-film compositions under his belt.

But Callobre doesn’t fit the bill of nerdy, studious classical musician (though a Google search shows he once did). Baby-faced — he definitely still gets carded on the regular — and sporting facial scruff, a black T-shirt, and dark-washed jeans, Callobre speaks calmly and slowly, with many a note-long “yeahhh” and frequent talk of meditation betraying his California roots. From the lime-cucumber-mint-infused water he offers me to the armadillo-skin charango he bought on Craigslist and has hanging on his wall, Callobre is decidedly hipster.

He wasn’t always a dedicated music geek. As a child, he ran through a series of piano teachers hand-picked by his parents; bored by classical music, he begged to try guitar when he was 4 years old. His parents said yes when he hit 7, but the classical stuff never went away. Instead, it stuck.

A talent for improvisation often goes hand in hand with making your own music — and Callobre was a veritable Mozart, beginning to compose at just 6 years old. At 11, he started to take classes with Grammy winner Bill Kanengiser. After Callobre had played for 10 seconds, Kanengiser recalls, “I almost fell over. He played with such mastery and incredible musicality.” Some years later, at college-picking time, Callobre chose USC, where Kanengiser is a professor and where Callobre was awarded the sole freshman faculty award (a full scholarship to a promising young music student). He started off as a triple major — in piano, guitar and composition programs — then dropped down to two, then one, then no specialties, graduating with a bachelor of arts in music, “the easiest music major you can have,” Callobre says, with a hint of rebellion, or maybe it’s a lurking slacker vibe.

Now, just a few blocks from his old campus digs, Callobre has itchy feet again. He has caught the movie bug and is seeking jobs in the film scoring world, where he’ll use his improvisational skills to compose the background music for big-screen productions. He’s in a good spot to pull it off, Kanengiser says, poised to meet the “movers and shakers” of the tough-to-crack industry.

It’s a little ironic: Callobre will be moving out of the spotlight and into darkened corners. Like the awkward cousin at a family reunion, film composers are always there but rarely command much attention. (You can probably name John Williams and Ennio Morricone and … anyone else?) Yet music is a crucial movie element — it can make audiences love or hate a character, feel scared or moved. Doing the job well requires a rigorous, “deep music background,” says Alison Plante, acting chair of Berklee College of Music’s film scoring department.

Yet Callobre’s decision makes sense — he has an intense desire to create funkier, freer music, and scoring for the big screen allows for alternative instruments and the possibility to compose in any genre, from electronic dance music to classical. Callobre dislikes excessively intellectualized music; he prefers not thinking about music “as if it’s something that can be explained.” No mystical obfuscating here. And he doesn’t typically spend hours searching for inspiration in his head; instead, he uses a trick learned from Pulitzer Prize–winning composer Steven Stucky. First, write a random sentence; second, turn each letter in the sentence into a number. Then assign each number a random note. It forces your fingers to move, Callobre says.

Obviously, Callobre is eager to make waves. But, as his professor Bruce Broughton says, there are still “holes in his education.” Broughton mentions the time he played Callobre a bit of musical theater. Callobre couldn’t recognize the music, enough to horrify an expert, though he says that Callobre’s not the only student to have such a gap.

Despite the chill vibe, and the occasional missing musical reference, Callobre is a perfectionist. “I have a feverish need for everything to be in a particular way,” he says. He gets up and demonstrates how he spent the morning arranging his furniture just so. Then he sits back down and grabs his guitar, playing any notes that come to mind.