The goal of Auditorium is simple: you have to direct flows of particles into their respective goal boxes. To do this, you have multiple tools provided at the start of each stage that affect the flow. But this simple task is only part of the experience. The gameplay feels a lot like being a conductor of an orchestra; once the particles hit a goal an instrument starts to play and will be joined by others in a beautiful melody when more than one goal is is hit. So don't even TRY playing Auditorium without sound, or you'll miss out on half of the game altogether.