His lawyer, Lloyd Zane Remick, said the cause was a heart attack.
Working with the producers and songwriters Kenny Gamble and Leon Huff, Mr. Sigler was a key figure in the development of the distinctive and very successful Philadelphia soul sound, characterized by lush orchestral arrangements and smooth vocals.
He wrote and produced songs for the OâJays, Patti LaBelle and many other acts on Mr. Gamble and Mr. Huffâs Philadelphia International label. In a 2008 NPR interview, Mr. Gamble said that he, Mr. Huff and Mr. Sigler had also provided background vocals on songs like Harold Melvin & the Blue Notesâ 1972 Top 10 hit, âIf You Donât Know Me by Now.â
In a statement, Mr. Gamble called Mr. Sigler âone of the most talented, creative and great songwriters and music producers I have worked with.â
Mr. Siglerâs productions for other labels included âI Got My Mind Made Upâ by Instant Funk, a No. 1 R&B hit on Salsoul in 1979.
Ms. LaBelleâs 1983 single âLove, Need and Want You,â written and produced by Mr. Sigler and Mr. Gamble, was later sampled by OutKast, Nelly and other hip-hop artists. âIf,â which Mr. Sigler and Phil Hurtt wrote and produced for the singer Jackie Moore in 1973, was sampled by Jay-Z on his 2001 track âThe Rulerâs Back.â
Mr. Sigler appeared on the Rootsâ album âGame Theoryâ in 2006.
Mr. Remick said that despite health problems that led to his being hospitalized for…