Abstract
This paper presents the results of the analysis of variations in frequency response and directivity pattern of the 2nd order pressure gradient directional microphone due to combining method of the element Ist order pressure gradient directional microphones. Especially discussed matters are the degradations of the frequency response and of the directivity pattern due to differences in the sensitivities, electrical impedances or directivities of the element microphones. The allowable difference in these values are obtained. The paper also presents characteristics of the 2nd order pressure gradient unidirectional capacitor microphone that have been realized.
