Abstract: An audio collecting device by audio input matrix comprises: a plurality of audio input devices for inputting audio sources and generating a plurality of audio signals; a plurality of sub-processors for connecting with a plurality of audio input devices to process the audio signals and generate audio processing signals of them, respectively; and a main processor electrically connecting with the plurality of sub-processors to process the audio processing signals as inputs for controlling these a plurality of sub-processors to do the synchronously sampling actions.