When Mr. Jones discovered him, Mr. Ingram had been inching his way into the music business for about a decade. He had been a pianist for Ray Charles; played in a band, Revelation Funk, which contributed a song to the soundtrack of the 1975 movie “Dolemite”; played in one of Dick Clark’s support bands; and done side work as a demo singer.

After the success of “Just Once” and “One Hundred Ways,” Mr. Ingram became a force in R&B. In 1982 he recorded a duet with Patti Austin, “Baby, Come to Me,” which reached No. 1 on the Hot 100. In 1983 he released his first solo album, “It’s Your Night,” which featured several hits, including another duet with Ms. Austin, “How Do You Keep the Music Playing?,” and “Yah Mo B There,” a duet with Michael McDonald that would earn Ingram his second Grammy, in 1985. (He was nominated a total of 14 times.)

Throughout the 1980s, Mr. Ingram worked with Mr. Jones on several other projects: participating in the all-star charity single “We Are the World”; writing for the soundtrack of Steven Spielberg’s film “The Color Purple” (1985); singing on Mr. Jones’s 1989 album, “Back on the Block”; and, most crucially, writing, with Jones, Michael Jackson’s 1983 Top 10 hit “P.Y.T. (Pretty Young Thing).”

“It’s almost like I got the chance to go to Oz and Quincy was the Wizard of Oz and Michael Jackson was who he was dealing with in his world,” Mr. Ingram told Jet magazine in 2007.

In a statement, Mr. Jones said: “There are no words to convey how much my heart aches with the news of the passing of my baby brother James Ingram. With that soulful, whisky-sounding voice, James Ingram was simply magical.”

Later in the 1980s and into the ’90s, a time when songs from hit films often became radio hits too, Mr. Ingram was a soundtrack favorite. “Somewhere Out There,” a duet with Linda Ronstadt from the animated feature “An American Tail,” was one of biggest chart successes, reaching No. 2. He was heard on the soundtracks of “Beverly Hills Cop II,” “Forget Paris” and “City Slickers.”