He was the voice of Eeyore on Winnie the Pooh, did gigantic gorilla grunts in 1976’s King Kong, and was even the announcer for The Smother Brothers Comedy Hour. But for thirty years, Peter Cullen has been best known as the commanding voice of Optimus Prime, first in the original Transformers cartoons, and later in the live-action movies, newer ’toons, and numerous video games.

With Transformers: Age of Extinction coming to theaters June 25th, and Transformers: Rise of the Dark Spark coming to the PlayStation 4, PlayStation 3, Xbox One, Xbox 360, WiiU, PC, and the 3DS on June 27th, we spoke to the man about where he got that wonderful voice and if he ever uses it to order pizza.

When you originally auditioned for the role of Optimus Prime, how many different voices did you try out before you found the right one?
Well, I didn’t have far to go for inspiration because that morning, when I was going to the audition, my brother Larry [a retired Marine Captain] asked me where I was going, and when I said, “I’m going to audition for the part of a leader. He’s a truck. But he’s a hero and a leader,” my brother said, “Well, then be a real hero. Don’t be a phony hero who yells and screams and stuff.” And since my brother had always been an inspiration to me — he was a real hero and a real leader — when I was at the audition, and started reading the lines, I started doing an impression of my brother. Not just his voice, which is deeper than mine, but an impression of his qualities as a human being. So the voice just flowed out.

It also helped that it was written really well. I have to give credit to the people who wrote the G1 cartoons.

I assume your brother knows you based Optimus Prime on him, right?
Yeah. I told him years later. One day, we were standing out on his porch, sipping lemonade, I told him, “This is a phenomenon, and you’re a part of it because I based the character on you.” And he was humbled by that, almost embarrassed.

You’re doing the voice of Optimus Prime in both the movie Transformers: Age of Extinction and the game Transformers: Rise of the Dark Spark. How is working with Michael Bay, who’s directing Extinction, different from working with the people making Dark Spark?
They’re similar. With Michael Bay, that’s an experience unto itself, having been intimidated by the fact that he’s a great director of these huge films. I actually had to audition for him twice. But our working relationship is wonderful.

When I worked on the first game, though, those guys were a joy to work with as well, but there was a such a respect for the character from the beginning. I wasn’t used to that, it’s something that’s transformed—pardon the pun—over the years.

Having voiced Optimus Prime for thirty years, you know him better than anyone. How often do you notice something in the script that you know he would never say?
There have been times like that. I’ve always gone with my gut instinct with this character, and I’ve fought for it on occasion. I don’t have any specific instances in mind, but I know there’s times when I’ve thought, “No, that’s not right, I can’t say it like that,” and then I would just say it the way I thought he should say it. And I’m glad I did, too. Because his qualities are significant, and they don’t change. Unless he became something other than what he was, which would have to be indicated in the script, but that’s never happened. He’s always been constant. He’s always been the leader, the moral leader, a true leader, humble, strong, and unchanging. Those have always been my guidelines.

So do you ever do Optimus Prime’s voice in real life, like when you’re ordering a pizza?
I can’t think of a time I’ve ever done that. I’ve done the voice when I’m asked to do it, I’ll do a few lines.

See, if I had that voice, I’d be doing it all the time. [in the worst Optimus Prime voice] “I’d like a large cheese pizza…”
Ha. That’s funny. But yeah, I don’t just do the voice on a whim. [in Optimus Prime’ voice] “Double cheese, please.”

Finally, of all the Transformers stuff that you’ve been involved with over the years, what has been your favorite to work on, and what has been your favorite just for your enjoyment?Hmmm…. What I enjoyed the most was working with the cast in the early days on the G1 cartoons. It was new and exciting, and we all played three or four different characters in the show. There was one time when I was doing Optimus Prime, Ironhide, and another character—I don’t remember who—and they were arguing back and forth. I got a kick out of that, arguing with myself. Those were fun times, back in the G1 days.

And is there one Transformers thing that you’ve just enjoyed watching? Or playing, for that matter?
I haven’t watched a lot of the shows. But I have grandkids, and they love it, they love the shows. And they love it when I do the voice for them.

[again, in the worst Optimus Prime voice] “Grandchildren, roll out!”
Yeah, that’s fun. It’s obvious when Optimus Prime’s voice comes out of my mouth that it has an effect on people, and not just my grandchildren. And that’s just an amazing feeling.

Interview by Paul Semel (@paulsemel)

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