Bananarama

Bananarama are an English female pop band who have had success on the pop and dance charts since 1982. Rather than relying on harmony, the band generally sings in unison, as do their background vocalists. Although there have been line-up changes, the group enjoyed most success as a trio made up of friends Keren Woodward, Sara Dallin and Siobhan Fahey. Following Fahey's departure from the group in 1988, Jacquie O'Sullivan joined the group for three years though, since 1992, Woodward and Dallin have continued Bananarama as a duo.

source: Wikipedia