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In this article, we're going to talk about the ideal room sizes and dimensions. This is such an important issue because nearly everybody gets it wrong, and if you get it wrong in the beginning, getting good sound in that room is always going to be a struggle. How do we determine what size room to build? Using a room that's available is not necessarily the right answer. First, we have to determine usage. We have to decide what we are going to do musically in this room. Is it two-channel playback? Is it home theater? Is it a control room? Is it a listening room? Because each usage dictates energy requirements and how large a room it should be. Each usage dictates the treatment that we're going to put inside the room. So the first thing we have to define is the usage.