Quarter Space

When a speaker or other sound source is placed in a free field the sound it produces is able to radiate in all directions (depending, of course, on the design of the speaker enclosure). When a sound source is placed against a solid barrier, such as a wall, that same amount of energy is radiated into the space on one side of the barrier only, or into “half space.” When a speaker is placed at a junction between two walls, such as in the corner of a room, it is said to be in a 1/4 space environment. This will yield an additional 3 dB of sound power level (particularly in bass frequencies) over a speaker in a half space environment and 6 dB over a speaker in the free field. For more information on this phenomenon see WFTD Half Space.