Meet the man whose voice became Stephen Hawking's

Stephen Hawking's computer-generated voice is so iconic that it's trademarked — The filmmakers behind The Theory of Everything had to get Hawking's personal permission to use the voice in his biopic.
But that voice has an interesting origin story of its own.
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Back in the '80s, when Hawking was first exploring text-to-speech communication options after he lost the power of speech, a pioneer in computer-generated speech