The Manhattan Transfer

The Manhattan Transfer was an American vocal group founded in 1969 in New York City, performing music genres like a cappella, Brazilian jazz, swing, vocalese, rhythm and blues, pop, and standards. They won eleven Grammy Awards. There were several incarnations and formations of the Manhattan Transfer, with each edition having different styles. The first rendition was in the 1960s, consisting of a mostly a cappella-tinged style; it featured Tim Hauser, Erin Dickins, Marty Nelson, Pat Rosalia, a... source: https://en.wikipedia.org/wiki/The_Manhattan_Transfer