Al Jarreau, whose smooth voice was a jazz legend for decades, dead at 76

Just hours before the Grammys, a music giant passed.

Seven-time Grammy-winning jazz singer Al Jarreau, who transcended genres over a 50-year career, died at a Los Angeles hospital Sunday, just days after announcing his retirement from touring because of exhaustion.

Those unfamiliar with his name may remember his iconic voice introducing mainstream TV viewers to Bruce Willis -- he sang the theme song to Moonlighting, long before Willis' Die Hard days.

His official Twitter account and website say he died surrounded by his wife, son and a few other family members and friends. He was 76.

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Jarreau was hospitalized earlier in the week and was said to have been improving slowly. The cause of his death was not revealed, but he had experienced a number of respiratory and cardiac issues in recent years.

The Milwaukee native's biggest single was 1981's "We're in This Love Together" from the album Breakin' Away. Jarreau was also a vocalist on the all-star 1985 track, "We Are the World," along with Michael Jackson, Billy Joel, Stevie Wonder, Willie Nelson, Ray Charles, Bruce Springsteen and many others.

Jarreau is one of the few artists to have won Grammys in three separate categories — jazz, pop and R&B. Time Magazine once called him the "greatest jazz singer alive."

News of Jarreau's death came as the Grammy Awards were kicking off in Los Angeles.

Tributes poured in on social media. Director Ava DuVernay tweeted that her mom used to play Jarreau's vinyl and that his voice made her happy.

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Actress Octavia Spencer wrote that Jarreau "had a mellifluous voice. Soothing. Beautiful."

Music wasn't always Jarreau's focus, however — he didn't even record his first album until he was 35. Born to a minister father and a mother who played the piano in church, Jarreau sang from an early age, but he was also an athlete who earned a master's in vocal rehabilitation and started his career as a counselor in San Francisco, playing jazz on the side. But he couldn't ignore his passion for performance and eventually gave up his first career to do music full time.

His final album, My Old Friend: Celebrating George Duke, was released in 2014.

Jarreau is survived by his wife, Susan, and a son, Ryan. In lieu of flowers or gifts, a donation page has been set up for the Wisconsin Foundation for School Music.

Additional reporting by Mashable.