One of the things that we saw in Hollywood in the late 1960s was an unfortunate collision in the workflow of film sound where the person who organised and created the sound effects turned this material over to somebody else, who sat at the mixing desk and mixed it. And sometimes it would work. There were many interesting soundtracks produced but proportionately, not enough by our likes. And what would frequently happen is that the sound effects editor and that team would hand this material over and then wait for the mixers to do right by it but frequently, that didn't happen. And the mixers would think, this is all very bad but I'll do the best I can with it. And the sound effects editors would be sitting in the back of the room saying, 'This person is making a mess of everything that I did and there would be arguments and, can't you do...  Raise this level, do this, filter that, shut up.' So the equivalent in photography would be as if there were no hierarchy between the camera operator and the lighting cameraman. So imagine the situation if the... Dougie Slocombe come, lights the scene and then the operator comes in and does whatever they want. 'No, no, no. You can't shoot that way. I didn't like... No, I'm going to do this', and so there would be a terrible friction there and to us, there seemed to be no reason to have this friction now.

Technically, there was probably a reason for that back in the '20s and '30s because sound was a very mysterious engineering and technical problem. With the invention of the transistor, that problem had begun to recede and the prices of equipment were now dropping. Now of course, they've dropped catastrophically, in a good way. Things are very inexpensive now but that process was beginning in the 1960s with the injection of the transistor into the process. So we thought, there's no reason that the sound effects editor cannot also be the person who mixes it. They made all the sound effects. They know how it should sound so just let them produce the final results. And so the largest capital investment that American Zoetrope made was in mixing equipment because we thought that this would pay off, very largely. This investment would double, triple, quadruple its power and I think we were right. And so that move which we started in San Francisco, in the late 1960s and carried through all through the '70s, now, that's generally accepted in the industry that somebody who is a supervising sound editor or a sound designer can also sit at the mixing desk and blend those sounds into the finished film.