Abstract
An audio and electrical signal converter which comprises a microphone array wherein a plurality of microphones having different central oscillating frequencies and different magnifying powers collectively compose an array structure. Each microphone comprises a first audio receiver, a second audio receiver and a differential amplifier. The output signals from the first audio receiver and the second audio receiver will be subtracted by the differential amplifier so as to generate an output electrical signal having a predetermined central oscillating frequency at the output of the differential amplifier. The microphone required in the microphone array can be selectively connected by the switching unit so as to select the microphone having the required central oscillating frequency and the magnifying power by the switching unit and outputting the output electrical signal of the microphone array. The microphone array can be composed as a practical audiphone after connecting with an amplifier circuit and the speaker.