Available Technology

An active noise reduction system is used to control noise in an enclosure. Pressure signals from within the enclosure are received by an array comprising no more than two substantially orthogonally placed pairs of acoustic sensors. One pair is arranged in an X-direction and the other pair is arranged in the Y-direction. The sensors are arranged in a plane that is substantially parallel to and near to an inner surface of the enclosure. The pressure signals and a reference signal are processed to generate an output signal to minimize energy density at the acoustic sensors.