The present invention provides an adaptive directional microphone system for enhancing an acoustic signal from a second direction and for reducing an acoustic signal from at least a first direction different from the second direction, the system comprising: an omni-directional microphone and a directional microphone being arranged in a closely acoustically-coupled way; an adaptive filtering circuit system for generating a first error signal e1(n) corresponding to an acoustic signal in which the acoustic signal from the first direction is reduced; and a post-processing filter system for producing a second error signal e2(n) corresponding to an acoustic signal in which the acoustic signal from the second direction is enhanced as compared to the acoustic signal related to the first error signal e1(n).