Bowers & Wilkins 2-way closed-box surround speaker system

The DS7 is a dedicated on-wall surround speaker, offering a choice of dipole or monopole dispersion in home theatre installations. The choice of mode is selected either via a switch located on the front baffle, or remotely, using a 12V trigger from the surround processor. In monopole mode, only the two drive units on the front face operate. In dipole mode, the front tweeter is disconnected; the two side firing drivers are brought into operation and the crossover frequency to the bass unit is lowered. The side units are connected out of phase with one another, which creates a wedge-shaped null zone at right angles to the wall. If the listeners sit in this zone, they become less aware of the location of the speakers and hear more reflected sound; hence the diffuse nature of the sound field.