Worldizing, an amazing sound design concept created by Walter Murch. Watch the video to know all about that process. There are at Filmsound one interesting article about Worldizing; Walter said:
George (Lucas) and I took the master track of the two-hour radio show with Wolfman Jack as DJ and played it back on a Nagra in a real space – a suburban backyard. I was fifty-or-so-feet away with a microphone recording that sound onto another Nagra, keeping it in sync and moving the microphone kind of at random, back and forth, as George moved the speaker through 180 degrees. There were times when microphone and speaker were pointed right at each other, and there were other times when they were pointed in completely opposite directions. So that was a separate track. Then, we did that whole thing again.
When I was mixing the film, I had three tracks to draw from. One of them was what you might call the “dry studio track” of the radio show, where the music was very clear and sharp and everything was in audio focus. Then there were the other two tracks which were staggered a couple of frames to each other, and on which the axis of the microphone and the speakers was never the same because we couldn’t remember what we had done intentionally.
Sometimes, Wolfman Jack would be on axis on one track, but he would be off axis on the other track. I was able to blend those three tracks to get the right amount of atmosphere. I could make transitions from a live, very present sound to something that sounded like it was very distant and bouncing off many buildings. I could create a sense of movement too – hence, the moving microphones.
Video vía usoproject