The Delfonics are an American R&B/soul vocal group, primarily popular during the late 1960s and early 1970s. Known for their smooth harmonies and falsetto lead vocals, they played a significant role in the development of the 'Philadelphia soul' style. The group's most notable members are brothers William and Wilbert Hart, the main songwriters and vocalists. Their hit songs "La-La (Means I Love You)" and "Didn't I (Blow Your Mind This Time)" are considered classics in the soul music genre, underlining the band's influence and enduring legacy.