J. Earl J. allowed artificial intelligence to voice Darth Vader
Actor James Earl Johnson has been the original voice of Darth Vader since the first Star Wars film, A New Hope, but at his 91, it would be problematic for him to participate in the character's voiceover, but there is a way out.
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Jones signed the rights to his archived voice work, allowing Ukrainian startup Respeech to use the actor's original voice in the Obi-Wan Kenobi series (yes, it was a generated voice!).
Certain fragments of Johnson's voice are used for "cloning," so now the actor's presence is not necessary at all. Skywalker Sound's chief sound editor Matthew Wood said that he suggested this option to Johnson when he remembered that he was planning to "roll up" the role of Vader. After getting permission, the studio commissioned the Respeech team to make his voice look like the one the Sith Lord had 45 years ago.
That's why Vader's voice in Obi-Wan sounds slightly different from Skywalker. Rise."
Source: The Verge