Microphone apparatus having a variable directivity pattern

A microphone apparatus comprising:

• an array of equally spaced microphones, the microphones being divided into a center subarray and a pair of side subarrays located one on each side of the center subarray;
• a first weighting network having a plurality of weighting factors for impressing a first weighting function on signals from the microphones of the center subarray.
• second and third weighting networks each having a plurality of weighting factors for impressing second and third weighting functions respectively on signals from the microphones of said side subarrays, said first, second and third weighting functions corresponding respectively to center and side portions of a sensitivity profile which varies as a function of positions on said array;
• a first adder for summing signals from said first weighting network;
• a second adder for summing signals from said second and third weighting networks;
• a third adder for summing signals from said first and second adders to produce an output signal;
• and
• level setting means for adjusting the level of an output signal from said second adder in a predetermined relationship with the level of an output signal from said first adder to provide a variable directivity pattern.