Success hasn’t changed Bob Cavallo.

“Bob is one of the few guys in the industry completely unaffected by the trappings that come with success,” says John Sykes, president of MTV Network Development, who has known Cavallo for decades. “He knows his priorities. He’s the same regular guy — whether he’s managing Prince or running Disney music — that he has always been,” says Sykes.

An ego-free, low-profile leader was exactly what Disney’s music operation needed after two previous high-profile, but mostly unsuccessful, regimes. After 35 years as a manager, guiding the careers of acts as diverse as the Lovin’ Spoonful, Prince and Earth, Wind & Fire, Cavallo signed on as chairman of the Disney Music Group in 1998.

“It was a new challenge, and something I thought could be fun,” he says. “And I didn’t know the record business was over yet,” he adds half-jokingly.

Under his aegis, the Disney Music Group — which includes four record labels and music publishing — has evolved from a moribund operation into one grossing nearly $500 million in revenues, according to sources (Disney doesn’t break out figures), and a 3.43% market share. While a single-digit share pales to some of its double-digit competitors, DMG nonetheless has the market cornered in music for the tween set.

Sales of music from Hannah Montana aka Miley Cyrus, Jesse McCartney and “High School Musical” are filling label coffers, and the acts are benefiting from high profiles due in part to constant exposure on Radio Disney and the Disney Channel.

“I knew early on we’d need to use the Disney Channel to overcome a lack of (non-Disney) radio play for our artists. The trick was how to use it properly,” Cavallo recalls. “Hilary Duff was the model. She became a Channel star and made a mainstream record that sold 3.9 million units. She certainly turned things around for us.”

Recent breakthrough: “Hannah Montana/Miley Cyrus seems to be what everyone is talking about,” but Disney Music also has new records from Raven-Symone and Duff on the horizon.

Role model: “I looked up to Albert Grossman (legendary artist manager in the era of Bob Dylan and others). If I was insecure about something, I’d call him up and ask what he thought.”

What’s next: “The Jonas Brothers, we believe, are going to be big. They’re making a film, have a TV pilot and will be the next wave. Plus, Grace Potter and the Nocturnals — the real deal.”