NEW YORK (AP) – William “Poogie” Hart, a founder of the Grammy-winning trio the Delfonics who helped write and sang a soft lead tenor on such classic “Sound of Philadelphia” ballads as “La-La (Means I Love You)” and “Didn’t I (Blow Your Mind This Time),” has died at age 77. His son told The New York Times that Hart died July 14 at Temple University Hospital in Philadelphia from complications during surgery. From the late 1960s to the mid 1970s, the Delfonics had six top 40 pop hits and more than a dozen top 20 R&B hits, defined by the rich orchestral arrangements and layered harmonies that made Philadelphia soul as essential to the ’70s as Detroit’s Motown label had been in the previous decade. (Photo: AP)