A Speaker Box (or Cabinet) is the physical structure that houses the loudspeakers (drivers) of a sound system.

Besides protecting and providing physical support to the loudspeakers, the cabinet design is one of the most important factors for the final sound of a speaker box, especially in the bass response. It is usually constructed of wood or wood composites (such as MDF), but it can also be made of metal, plastic, or other materials. There are two main types of design: Sealed Enclosure: The cabinet is completely closed. This design is known for a more precise, controlled bass response and a smoother, more natural roll-off. Vented Enclosure: The cabinet has an opening (port or duct) to take advantage of the sound energy from the back of the speaker, reinforcing the bass. Examples include bass-reflex, transmission line, and ATL designs. These designs generally offer more bass extension and efficiency, but with a more abrupt roll-off.