Cue or interact?
The most common way of controlling sound in a theater performance is by cuing it; the sound engineer starts and stops the different sounds at predetermined times through the performance, and the actors may also cue their actions to predetermined cue-points in a sound passage. This is in fact also interaction through sound, in the same sense as several musicians playing together. The sound engineer interacts with the actors and the other people involved (the light engineer, the crew behind the stage, etc.) to create a total experience where all the parts fit smoothly and synced together. Manual cuing is the simplest way of placing sound right in a performance; whenever cuing is the best solution to a problem, then cue.
So when is it a point to use sensor technology for such interaction? Sensor interaction should not be just for the sake of using sensors; it should add something to some part of the performance and the experience of it. But that's not to say that everything cueable is better off cued. Making sound interactive changes the way the actors relate to the sound, which in turn changes the audiences experience. When an actor interacts with a computer system, there's a possibility of zero reaction lag and a more organic relationship between the sound and the action on stage. The actor does not wait for the sound to be cued; he makes the sound himself, and explores the sounds of the stage surroundings, just like anyone would explore and experience in real life.
