As well as being the alto saxophonist and flautist in Kool & the Gang, Dennis “Dee Tee” Thomas, who has died aged 70 in his sleep, was also the band’s master of ceremonies. This role earned him an enduring moment in the group’s history when he delivered the opening monologue to their single Who’s Gonna Take the Weight (1971).

Deploring the chaotic state of the world, Thomas warned listeners that “we’re the ones who created it and we’re gonna have to be the ones who clean it up.” He warned that a higher judge will want to know “who’s creating all this corruption and death and pollution … and He’s gonna want to know who’s gonna take the weight”.

It’s a sentiment that does not sound out of place today, though it might be startling to listeners familiar only with Kool & the Gang’s 1970s dance and disco hits such as Jungle Boogie, Celebration, Get Down on It or the smooth, smoochy Ladies Night. Yet, as Thomas explained to Black Music magazine in 1975, in the late 60s, before they called themselves Kool & the Gang, the group “got involved in what you might call the hippy revolution. We were all getting very politically orientated and were very much involved in the changes that American youth seemed to be going through.”

They had enjoyed some success on the American R&B charts in the late 60s and early 70s, but it was the Top 30 hit Funky Stuff (1973) that set the Gang on the road to pop stardom, swiftly followed up by Jungle Boogie (No 4) and Hollywood Swinging (6). However, though their song Open Sesame featured on the Grammy-winning Saturday Night Fever soundtrack, their popularity took a dive with the arrival of the disco craze.

It was the recruitment of new vocalist James “JT” Taylor, a former New Jersey nightclub singer, and their hook-up with Brazilian producer Eumir Deodato that ignited the bestselling phase of the Gang’s career, when they scored three platinum-selling albums in succession (Ladies Night, Celebrate! – whose first track is Celebration – and Something Special) and a string of hit singles into the mid-80s including Joanna, Fresh, Misled, Cherish and Stone Love.

Thomas was born in Orlando, Florida, and his family later moved to New Jersey. The group came together in Jersey City in 1964, when Thomas and six school friends from Lincoln high school joined together as the Jazziacs, aiming to play jazz and R&B music. Bass player Robert “Kool” Bell recalled how “we used to listen to Miles Davis, Charlie Parker, Dizzy Gillespie, guys like that. We wanted to play that way so bad it hurt.”

Initially, it was a struggle. “At that time we was broke, as most ghetto people are,” said Thomas. “I mean really no money … If you played in the school band they’d let you borrow an instrument, but I didn’t even play in the school band ... I never had my own instrument until Kool & the Gang made their first record.”

The group met the local promoter Donald Key, who found them work backing a variety of singers. “We were called the Soul Town Review for the R&B gigs we did,” said Thomas. “We played all the Motown things, whatever was hitting big.” If they had a night off, they would play jazz in local coffee houses.

After a spell as the New Dimensions, they were spotted by the R&B producer and songwriter Gene Redd, who signed them to his new New York-based label De-Lite. They now became Kool & the Gang, and released an album of the same name (1969). This reached 43 on the R&B chart, while the title song reached No 59 on the pop chart. The group were making a living through steady touring, but became frustrated by the lack of strong record sales.

“We began to look at ways of breaking through, bypassing the radio,” Thomas recalled. “The discotheques were springing up and we could see what they were into. We needed to make a much harder, funkier, tighter kinda thing than what we’d been doing. So that’s how we did Funky Stuff.” He admitted that “most of us don’t go to discos”, but the impact of Funky Stuff was spectacular. “We got to a white audience who’d never heard of us until then, national television, all the big shows.”

The Gang’s hit-making days dwindled after the album Forever (1986), which reached 25 on the US chart, but their music enjoyed a second life as they became a favourite source of samples for hip-hoppers, with artists such as Cypress Hill, Jay-Z, P Diddy and the Beastie Boys dipping into the Gang’s audio goldmine.

They were also popular with Hollywood, with their songs featuring in films including Pulp Fiction and Rocky. The group won two Grammy Awards and notched up 31 gold and platinum albums. In 2014 they received a Soul Train lifetime achievement award, and in 2015 a star on the Hollywood Walk of Fame. In 2020 the song Celebration was inducted into the Library of Congress national recording registry.

The band described Thomas as “the quintessential cool cat in the group, loved for his hip clothes and hats, and his laid-back demeanour”.

He is survived by his wife, Phynjuar, daughter Tuesday, sons David and Devin, brother Bill and sisters Doris and Elizabeth.

• Dennis “Dee Tee” Thomas, musician and songwriter, born 9 February 1951; died 7 August 2021