An audio device includes a plurality of control cards and an audio unit. Each control card has an edge margin provided with an identification label for identifying the same. The identification label includes an insulator portion and at least two electrically connected conductive strips on the insulator portion. The audio unit includes an audio housing formed with a card slot to permit extension of the edge margin of one of the control cards into the audio housing, and a memory module disposed in the audio housing for storing digitized audio data corresponding to the control cards therein. A control circuit controls the output of the digitized audio data from the memory module. A plurality of electrically conductive stripes connect the control circuit to the identification label on the edge margin of the control card that is extended into the card slot of the audio housing. The conductive strips of the identification label connect electrically some of the conductive stripes so as to generate a unique card identifying signal that is received by the control circuit and that is used to activate the control circuit for controlling the memory module to output a selected one of the digitized audio data in accordance with the card identifying signal.
