Term: Room modes

Room modes are resonances or standing waves in a room or enclosure caused when the distance between two opposite boundaries (walls, floor, ceiling) is equal to half a wavelength. For instance, two walls that are 11 feet apart will create a standing wave resonance at 51 Hz. Axial modes occur between two opposing boundaries, tangential modes occur when sound reflects between two pairs of opposing surfaces, and oblique modes occur when sound reflects off of all six room boundaries. Modes create areas of high and low amplitude for specific frequencies throughout a room.