ABSTRACT
There are three basic requirements for sound to exist in the physical world. First, there must be a sound source, such as a gunshot, which generates acoustic energy. The acoustic energy must then be transmitted through a medium such as air, water, or drywall. Finally, a receiver, such as a microphone or a listener’s ears, must pick up the acoustic energy. Once acoustic energy enters the ears, it is converted to nerve impulses and directed to the brain. The brain then processes these impulses to produce a subjective interpretation called sound. The animator creates the first two conditions, the sound designer represents these conditions with sound, and the audience completes the process. Another way in which we experience sound does not follow this model-a process known as audiation, which is a mental rather than a physiological process. As you are silently reading this book, the words are sounding in your brain as if they were being produced in the physical world; however, these sounds are not a direct product of your hearing mechanism. Just as animators visualize their creations, composers and sound designers conceptualize their creations through the process of audiation. Voice over (in the first person) allows us to hear the thoughts of a character, an example of scripted audiation (Figure 1.1).
