And we used that in the mix and we not only used that in the mix, but this was given to the sound editors so that if a sound editor was working on Scene 86, they would know, oh this is mono, therefore my work is much simpler now. But this scene, the big battle scene, it's full so now I have to really do... I have to arrange everything to really take advantage of this space, but that allowed the sound editors to figure out how to apportion their time correctly. They didn't have to do everything in full all the time.

In fact, probably... I forget what the statistics would be but it's probably, in the end, probably only half of the film is in full six track. And much of the film is, in fact, mono. And it's something that I would recommend to film-makers to do. And it was out of this exercise that the term 'sound design' arose because in the end I was asked, 'Well, what do you want as a credit?' So, I had edited the picture and I got credit for that and I had also sat at the mixing desk, but I had also been responsible for the overall design of the sound.

And I thought, well, just like a production designer arranges things in the three-dimensional space of the set and makes it interesting to look at, I'm essentially doing the same thing with the three-dimensional space of the theatre. Where are we going to use it in full and where are we going to not use it, even though we could? Where are we going to hold back and where do we expand and where do we contract? And that is a kind of design, so that was the, in this particular case, that was the origin of the term 'sound design.'

Since then, sound design has come to mean all kinds of other things, which is... One example is, I am creating sound effects that have never been heard before, and so I am designing these sounds. There is no sound for the roar of the dinosaur so I am going to combine six or seven different sounds to give me the sound of a dinosaur, so I have designed the sound of a dinosaur. And that is another term for what sound design would mean, but the essence of it really goes back to what we thought we were doing at the beginning of American Zoetrope, which was giving to sound the same hierarchy that existed to picture.

So, just as there is a director of photography, there is also, in this case, a sound designer. Just like there's a production designer and if the director wants to talk to somebody about sound and somebody who is responsible for the whole sound, the way the director of photography is responsible for the whole image, then that is that one person. And in the case of Apocalypse Now, that was me.