For fourteen weeks across the summer and fall of 2005, Mariah Carey's "We Belong Together" sat at No. 1 on the Billboard Hot 100, a run that tied it as the second longest in the chart's history and made it the top song of the decade, according to Stereogum. Manuel Seal helped write and produce it. The songwriter, producer, and multi-instrumentalist, a central architect of the So So Def sound alongside Jermaine Dupri, died on September 27, 2026, at 66, Yahoo Entertainment reported, citing an announcement Dupri made on Instagram.

Seal grew up in Chicago before making his name in Atlanta's R&B and hip hop scene of the 1990s, where he became Dupri's closest musical collaborator at So So Def Recordings. Their partnership produced some of the era's defining records: Seal wrote and produced Xscape's "Understanding," co-wrote Carey's 1995 single "Always Be My Baby," lent his voice to the hook of Da Brat's breakthrough single "Funkdafied" that same year, and picked up multiple writing credits on TLC's multiplatinum album CrazySexyCool. When Usher released his sophomore album My Way in 1997, Seal had a hand in writing and producing its title track along with the singles "You Make Me Wanna" and "Nice and Slow," songs that helped establish Usher as one of R&B's defining voices.

Seal's reach extended well beyond So So Def. Over three decades he worked on records with Aretha Franklin, Destiny's Child, Xscape, Tyrese, Alicia Keys, Gerald Levert, and Marc Dorsey, building a catalog that made him one of R&B's most reliable hitmakers even as his own name stayed largely behind the credits. That body of work earned him six Grammy nominations across two decades, one of them a win for Best R&B Song at the 48th Annual Grammy Awards in 2006, shared with Carey, Dupri, and Johnta Austin for "We Belong Together," according to the Recording Academy.

Dupri announced Seal's death in an Instagram post, writing, "Today I lost the first person to really understand me musically. He had an answer for every one of my ideas." He added, "I'm so hurt, but I also thank God for blessing me with the experience."

The sound itself endures: the hook under Da Brat's verses, the chord changes beneath Usher's falsetto, the fourteen weeks Mariah Carey spent atop the charts on a song he helped build from nothing. Anyone who has heard those records has heard Manuel Seal, whether they knew his name or not.