An audio signal processing device includes multiple input reception units to which analog audio signals, on which watermark information indicating identification information is superimposed, are input, an extraction unit that is adapted to extract the identification information from each of the analog audio signals input to the multiple input reception units, and a display unit for performing display depending on the identification information extracted by the extraction unit in correspondence with the input reception unit to which the analog audio signal, from which the identification information is extracted, is input, or signal processing unit for performing signal processing depending on the identification information extracted by the extraction unit for the analog audio signal, from which the relevant identification information is extracted, and outputting the processed analog audio signal.