High-mounted corner speakers, wired through the walls, delivering whole-floor surround sound without a single speaker on the floor or on a shelf. The project was part practical — reclaim floor space — and part acoustic experiment. Mounting speakers at ceiling height in the corners of a room changes the sound field in ways that are hard to predict from spec sheets alone. The installation required fishing wire through finished walls, custom mounting brackets, and learning more about room acoustics than I expected to need.