ventriloquist

vatsastapuhuja A person, especially an entertainer, who practices ventriloquism.
1871, Plato, translated by w:Benjamin Jowett|Benjamin Jowett, s:Sophist The Sophist:

Most ridiculous is the discomfiture which attends the opponents of predication, who, like the ventriloquist Eurycles, have the voice that answers them in their own breast.

"Oh, I am a ventriloquist," said the little man. "I can throw the sound of my voice wherever I wish, so that you thought it was coming out of the Head. (..)"