soundalike

/ˈsaʊndəˌlaɪk/
noun
  1. A person or thing that sounds very similar to another, especially a famous person or performer.
    • The band hired a soundalike to perform the old hits while the original singer recovered.
    • She made money as a celebrity soundalike, voicing commercials for a famous actress.
    • The radio contest winner was a perfect soundalike for the pop star.