Instead of bringing Hamill in to record the new lines of dialogue, the series — including
The Mandalorian, apparently! — instead used a program called Respeecher to make Luke sound like it’s 1983 all over again. Sound editor Matthew Wood described the process in an episode of
Disney Gallery: Star Wars: The Mandalorian: “It’s a neural network you feed information into and it learns. So I had archival material from Mark in that era. We had clean recorded ADR from the original films, a book on tape he’d done from those eras, and then also Star Wars radio plays he had done back in that time. I was able to get clean recordings of that, feed it into the system, and they were able to slice it up and feed their neural network to learn this data.”