Carl Wilson, a founding member of the Beach Boys, whose music helped define the Southern California lifestyle, has died from complications of lung cancer, the band's publicist said Saturday. He was 51.

Wilson died Friday in Los Angeles with his family at his side.

Throughout his nearly four-decade career, Wilson was known for his sweet-sounding voice on such songs as "Wouldn't It Be Nice" and his stabilizing presence during the band's sometimes tumultuous history.

"Carl Wilson could sing anything. He could sing the phone book and he would sound great," said Andy Paley, a songwriter and staff producer for Sire Records.

Wilson was diagnosed with cancer last year. Still, he continued to press ahead with his music while undergoing treatment, said Alyson Dutch, the band's publicist.

He played with the Beach Boys for the duration of their 36th annual tour last summer and appeared to be in good spirits. "He was doing very well," Dutch said.

Wilson was born in Hawthorne and began playing the guitar as a teenager. He and his brothers Brian and Dennis, cousin Mike Love and friend Al Jardine founded the Beach Boys in 1961.

The Southern California quintet made its first public appearance on New Year's Eve in 1961 at Long Beach's Municipal Auditorium.

Dennis Wilson, who was killed in a swimming accident in 1983, came up with the idea of a surfing theme for the music. Brian Wilson and Love started writing lyrics, capitalizing on the surf music craze that had begun in the mid-1950s.

With their quick guitar riffs, harmonic sounds and catchy lyrics, the band helped define the "surf sound" and in the process shaped the quintessential image of Southern California.

Between 1962 and 1966, the Beach Boys registered more than a dozen top 20 singles.

"As far as a super group goes, they're the nearest thing America has to the Beatles or the Rolling Stones," said Steve Brigati, a rock music historian.

Wilson was blessed with a pitch-perfect voice that helped form the backbone of the band's classic sound. He played the guitar and was the band's lead singer on many of their classic recordings, including "Good Vibrations" and "God Only Knows."

Wilson was a stabilizing presence over the years, as the group was torn by family feuds, drug abuse, fame and the death of Dennis Wilson.

"Carl was like a rock for the group. He was the steady one. He was the tiller," said Sandy Friedman, executive vice president of Cowan and Rogers, who was the Beach Boys publicist from 1975 to 1992.

In a 1985 interview with The Times, Wilson acknowledged the hard road that the band had traveled. "Sure, we've had our fair share of ups and downs," Wilson said. "But I don't know if we've had more than any other rock band. . . . We just have a way of getting ourselves into hot water."

Although he was the group's emotional leader, Wilson was a private person who often preferred to shy away from the spotlight, recalled cousin Stan Love, brother of Mike Love.

"He never wanted credit for their success, but he was the glue that held the band together," Stan Love said. "Whenever you saw a great Beach Boy concert you saw what Carl Wilson was bringing to the stage."

High school classmate and musician Rick Henn said Wilson remained a down-to-earth person, never letting his fame get the best of him.

"He was one of the kindest and nicest people that I'd met that had become a star. He was genuinely a sweet, caring and loving guy," said Henn, who played with the Sunrays, which toured with the Beach Boys. "That being said, he was also a wacky guy. He had a madcap personality and great sense of humor."

In the early 1980s, Carl Wilson said he tired of the Beach Boys' focus on nostalgia and lack of musical growth. He left the group in 1981 and released a solo album that year.

But he rejoined the group and had performed with them ever since--including the Beach Boys' induction into the Rock and Roll Hall of Fame in 1988.

Though he was in generally good spirits, his mother, Audree, died recently and he had been spending time with his family, Dutch said. The family was in seclusion Saturday.

"It's the passing of a legend and a musical genre that not only affected the lives of the fans here but of people around the world," Dutch said.

Private burial services were planned for later this week.

Wilson is survived by his wife, Gina, and two sons, Jonah, 28, and Justyn, 26, Dutch said.

Carl Dean Wilson