In music, a baffle is a partition that prevents sound waves from interfering with each other. Baffles are used in speaker cabinets. It is the surface that the speaker is mounted to, and its original purpose was merely to prevent sound waves from the rear of the speaker from interfering with the waves coming out of the front of the speaker. Without a baffle they would tend to cancel each other out, especially at low frequencies. Just hold a raw speaker up in the air with a signal running through it to see for yourself. In order for a baffle to work at low frequencies it would have to be very, very large to prevent the long wavelengths from wrapping around and canceling each other. The workaround for this is the speaker cabinet, which encloses the speaker and prevents a lot of interference. Modern speaker cabinet designs have greatly expanded on the basic baffle with all kinds of little tricks and designs to improve the sound. Some basic designs include bass reflex, acoustic suspension, and horn.