Patent ID: 8699739
Filing Date: 2014-04-15
Classification: H04R

Abstract:
1. A boundary microphone comprising: a base made of metal; a cover that is made of metal and has a plurality of holes through which a sound wave is guided; a plurality of microphone units each of which converts sound into an electric signal; and a plurality of microphone unit holders slidably provided on the base, each of which holds a microphone unit of the plurality of microphone units, wherein each of the microphone unit holders has a knob, the base has a plurality of slot shaped through holes wherein a knob of a microphone unit holder penetrates the base through a through hole of said plurality of through holes, and each knob and each through hole for each microphone unit holder form a microphone unit position changing unit with which the respective microphone unit holder is movable with the microphone unit by a movement of the knob within a range defined by the through hole, and wherein the microphone units are radially arranged on the base, the microphone units are disposed at equal angular intervals in the circumferential direction of the base when the microphone unit holders are each positioned at a first end of a corresponding through hole, and the microphone units are disposed at non-equal angular intervals in the circumferential direction of the base when the microphone unit holders are each positioned at a second end of the corresponding through hole.