Ben Burtt has been a Hollywood sound designer for more than 30 years and has produced sound files for some of Hollywood's film legends: Star Wars, Indiana Jones, E.T., and now Pixar's "Wall-E." Where others might watch fims and be interested in the set design or costumes or actors, he listens to hear new sounds he can capture for future use. In a recent interview, he talked about the large number of sound files required for "Wall-E" and some of his more unusual E-Bay purchases.
What are the challenges in voicing a character like Wall-E?
Ben: Well, the challenge of doing robot voices. Andrew could have, if he wanted to, hire actors to stand in front of a mic, and record their voices. Then you just dub that in over the character’s action. But that would have, of course, not taken the whole idea of the illusion very far.
What he wanted was the illusion that the robot characters’ speech and sounds they made were really coming from their functions as machines. That there was either a chip on board that synthesizes voice, or the squeak of their motor would sound cute, and that would kind of give an indication of how they feel.
For me, the problem does go back to the sort of primal R2-D2 idea, which is how do you have a character not speak words, or in the case of Wall-E, a very few words, and yet you understand what’s going on in their head. And they also seem to have a depth of character. The trick has always been somehow to balance the human input to the electronic input to it, so you have a human side of it.
In this case, Wall-E ended up being my voice because I’m always experimenting on myself. It’s sort of like the made scientist in the lab, you check yourself with the serum. After weeks and months of experimenting, it was obviously easier to try it with myself.
You start with human voice input. You record words or sounds, but then it’s taken into a computer. I worked out a neat program which allowed me to deconstruct the sound into its component parts. We all know how pictures now are in pixels, and you can rearrange the pixels. You can kind of do the same thing with sound.
I can do that with the Wall-E vocals. I can reassemble the vocals and perform it with a light pen on a tablet such that you can change pitch by moving the pen, or change the pressure of the pen. It will stretch syllables or consonants to alter the performance. It’s kind of like playing a musical instrument.
But that process had artifacts in it, things that made it unlike human speech. Glitches you might say. They were things you might throw away if you were trying to convince somebody it was a human voice. But that was what we wanted, we liked, that electronic, kind of alien thing, that went along with it. It helped make the illusion that the sound is coming from some kind of voice box, circuits in the character.
So it’s a matter of that relationship; how much electronic, how much human. You sway back and forth and create the different sounds.
A great deal of the sounds for him and the other character are sounds effects, which are chosen with the robot’s character in mind. Wall-E’s character has lots of little squeaks and clicks of his hand. Those are all mechanical sounds that come from many different sources. The idea is to orchestrate all those little bits of sound to also be part of his character.
He can cock his head and look at something with a funny little squeak, and it’s an expressive sound effect. It’s really that array of sounds that helps define the character.
People who know you say you used to jump up at the crack of dawn when you’d hear the garbage trucks to go out and record them. Do you still do that?
Ben: Yes. Every film seems to soak up and use everything I’ve got because there’s always something more we need. I’m always on the look for new things. They’re hard to find! I’ve recorded so many airplane sounds, so many electronic noises. For a while, the team recorded every motor we could find, from vehicles to appliances, jet planes, whatever. We just went wild.
The world is full of sound, and for a science-fiction film like this, I’ve found that the idea of taking real natural sound and imposing it into the fantasy film gives the illusion that these things are real because you kind of recognize them. People can’t identify them specifically, but you say, “Oh, well, that sounds like it’s really a motor, so I believe it.” So it’s a trick that works really well.
There were more sound files in Wall-E than any feature film I’ve worked on. There were 2500. That’s because every character has a set of sounds, and there’s a lot of movement, a lot of activity.
Can you give us some examples of the stories behind some of the sounds?
Ben: Wall-E’s treads are interesting. He rolls around and goes different speeds. When he’s going slowly, that’s a sound I heard in a John Wayne movie called “Island in the Sky” on Turner Classic Network. It’s a soldier turning a crank to generate power.
I said, “I like that generator sound, it’s cool. I wonder where I can get one?” I found one on E-bay and bought it. It came in its original 1949 box, and I took it into the studio and recorded it. But that’s only good when Wall-E’s going slowly.
When he’s going fast, I needed something high-pitched and more energetic. Once again, I went back to my memory of things. I recorded bi-planes a long time ago for “Raiders of the Lost Ark.” The old 1930s bi-planes have what’s called an inertial starter. It’s a hand-crank that cranks the engine. When you do it by hand, the clutch connecting makes a wonderful whirring sound.
I thought I could do something with it. But I couldn’t bring a bi-plane into the studio, so I went on E-bay and found an inertial starter! So I bought it and brought it in.
It’s a tradition in animation that goes back to the days of Disney cartoons to have sound effects machines: wind machines, or boing machines, things like that. So we built machines to make Wall-E’s sounds like that.
Eve is a very high-tech robot, so rather than the motor sounds and the squeaks that go with him, she’s very quiet. She’s held together by some sort of force field and magnetism, so a great deal of her sound is purely synthesized musical tones that I could make with a music synthesizer and treat it in various ways.
Her whole character was supposed to be graceful and ethereal. So she always has an electronic sound associated with her character when she’s floating around. Sometimes she sounds angry, or there may be a scene in which she’s aggressive. Sometimes she sounds enchanting.
In most animated films, the voices are recorded first, then the animation is created for the voices. How did it work in Wall-E?
Ben: Normally in animation, the voices are recorded first and locked down. Then the animators use that as references for timing and performance. We did kind of the same thing with this film. I started three years ago working on the dialog for this job, and started auditioning voices.
At first I made up sounds as auditions for Andrew. I’d play sounds of motors and ask him, “What do you think about this? Do you think this could be Wall-E?” He might pick out the things he liked the most, and we’d set that collection aside. I was putting together little montages, and then we’d give them to animators.
The animators would just freely animate to the sounds. Wall-E would come in and play with a ball or slip and fall. There were numerous tests, and I could see immediately the huge input into performance the animation had.
You’d think I would know better, but I was surprised they could do amazing things with little movements of the head. The sounds seemed so much more authentic when they were paired with the animation. So we went back and forth, working on the development together. So we’d wind up with these little character studies.
They were like audition tapes. The character would come in, introduce themselves and talk and show off their functions. We’d hear it and see it and feel confident after a while that this was what Wall-E should be, and what Eve should be. Then they could move ahead and start animating the movie itself and move forward with building the movie. It’s a back and forth process.
The quality of the artistic presentation and the sound design was incomparable. Does the social commentary that emerged concern you?
Ben: I can’t represent the thinking of the film on that level. I know that through the years of my work on the film, from the time Andrew pitched it to me, at the forefront of it was this love story. It was kind of a Buster Keaton movie with someone stranded on a deserted island. A female character enters the scene, he falls in love with her, and chases her back to the big city. That was always the center point of the story.
The world that was set up with the demise of civilization coming about through commercialization and no exercise and so on. That was the setting for the science fiction part of the story. In the screenings, we’re seeing a lot of reaction to that. My point of view was that it wasn’t a lot of emphasis on that.
But you know, the Disney overseers give Pixar a lot of freedom for the directors to write and pursue their story. It allows a message to come out that may be very personal and not necessarily corporate, to be very individual.
I never sensed, or was part of a discussion, where having a political message was a goal. It was always “how do we set up the science fiction?” We wanted to create a world, so we had to define the problem. What’s it about, how did Wall-E get stranded here, and why are the humans missing?
Well, we had to set that up with a very appropriate series of events, which is an extension, perhaps, of the present. Where would that take us? That’s all I saw.
How important was it to you to go back to original sources for these sounds?
Ben: People think in this age of computers that we can do anything, the way we see visual effects have leaped forward lightyears. It isn’t the same with sound. It’s not the same dimension. The digital technology has allowed us to work quicker and you can practically do the sound for a movie from your laptop computer with a few additional pieces of equipment.
Whereas 25 years ago you had to go into the studio and record with engineers and many people. So it’s a very personal tool now to do sound because it’s digital. But the films I’ve worked on, you’re always trying to create this illusion that in a fantasy world, things are real. The style I’ve always followed is to go out in the real world, get real sounds, and impose them in the fantasy world to convince people that these fantasy objects are credible.
So it’s been successful to go out and get a real sound. I also love the history of sound effects. I love working for Pixar and Disney because there’s this touchstone, this history of sound effects creativity that goes back to the 1930s. They used to build all kinds of machines. There was a machine to create the sound of flying insects, there’s a machine that does a talking clock spring.
They’ve got an archive of these machines out there in Burbank, and I love that. I look at what a sound effects man does, and I love the tabletop props and things like that. It’s the style.
Do you find over the years as films become more reliant on CGI, that your job becomes more important, to ground us in reality?
Ben: Certainly, as I said, in a fantasy film the sound is usually the thing. It affects people more invisibly. I think you can be a bit more of a magician with the sound because people just aren’t aware of what we can do. I think it’s a compliment when people stop and say, “Oh, I guess it does sound like that!”
Every sound, every footstep, every explosion, someone had to decide what that sound would be and create it.
Of course, in this special-effects-driven era, certainly the most money is spent on these huge sets and concepts. The sound becomes that aspect of those films that holds them together and tries to convince the audience that it’s dramatic and real, even when in fact, in some cases, it doesn’t look all that good.
Sigourney Weaver was the voice of the computer, and it was great. Was there any attempt to make it sound like something from “Aliens?”
Ben: Well, of course Andrew and I are fans of “Alien” and all its sequels. I worked on the first “Alien” movie and made sounds for the mother computer. Her voice was recorded straight in the studio, but during the mix of the film, it was put in an echo chamber so it becomes very big and comes from everywhere. You actually never see the source of it; a speaker, or anything. It’s the broadest-range, highest fidelity voice in the movie. It represents being omnipotent and all-powerful, I guess.
What sound was the most difficult?
Ben: Voices are the hardest because the audience listens to them with a much more critical ear than sound effects. Of course, we’re all experts in nuances of speech, and when something is interpreted as a vocal expression, the audience is listening very carefully. Creating all these different characters (there are a dozen types of voices in the film) with unique sounds is challenging.
There’s everything from Eve and Wall-E to this vacuum-bot that makes this sound similar to when you run a vacuum cleaner. We used sounds that we did in third grade, but got in trouble for them. Everything was done with a vacuum cleaner for that character.
Was there ever a point where the voices were more computer-ish?
Ben: With my experience with Star Wars, I knew the dangers of going too far with things. So with Wall-E, I worked with Andrew all the time, and the development was slow. It came from the human side and moved into the electronic side. There wasn’t a time where there was an extreme either way.
We thought originally Wall-E might just beep and whistle and sort of chirp like R2-D2, but that changed.
Where did some of the other sounds come from?
Ben: His eyebrow is the sound of a Nikon camera shutter. His arms are the sound of a tank cannon – the asthmuth motor on a tank cannon. It was Andrew’s idea to have the Mac boot-up sound.
I refer to some of these things as “audio puppeteering.” You’re kind of behind the scenes with whatever means you can to interact. It might be your hands, or your voice, or a piece of equipment. Somehow the output is sound, hopefully expressive sound when it comes to vocals for character.