I created the voice for E.T. out of many different things, about 18 different people and animals and sound effects. There are racoons in there, there are sea otters, there are some horses, there's a burp from my old cinema professor from USC (University of Southern California). There's my wife's laboured breathing asleep at night with a cold. I'll take sound from anywhere and use it if it'll get me the effect I want.
Is there any one sound of yours that's like a trademark that goes through most of the things you've done?
There are probably many little trademarks of sound. I don't think I consciously put things in. I used to put a scream in called the Wilhelm Scream which was in every movie I did but that was just a joke to impress another friend of mine named Richard Anderson. We were both students together and we both put that scream in all our movies to out do each other.
But then the public began to recognise that and there are cults now around the Wilhelm Scream. There's not a Wilhelm in WALL·E but there are other sounds. In every movie I think I've got bit of my grandfather's hand radio set. I recorded some electronic sounds, tuning stations, back 40 or 50 years ago. And I have used a bit of that Morse code, that side banding, short wave sound in some form in every film I've ever done.[read the interview - via BBC]