Abstract: A directional micro-phone is disclosed which comprises a microphone array (3) having a plurality of microphone elements (4,5,12,13) of which the element (4) is a rear element and the other elements arc forward elements. A processor (19,31) is connected to the elements. The processor can be a hardware processor for processing signals or it can be a software controlled system for processing signals. The processor one of the forward elements (5,12,13) and thereafter establishes a window of opportunity for receipt of the wave at the rear element (4). The window of opportunity is set such that only waves emanating from a particular direction will arrive in that time frame, thereby enabling acoustic waves from that direction to the process by the microphone and other waves from different directions eliminated. The angle of arc of the microphone from which acoustic waves are received and processed can be set by changing the size of the window of opportunity t3-t2.