An electronic volume apparatus sets an amplification factor (Gamp) of a digital potentiometer in response to a requested sound volume value (Vreq) transmitted thereto from a remote controller and sends back an actual result sound volume value (Vrep) with respect to the requested sound volume value. A coordination relationship among requested sound volume values (Vreq), actual result sound volume values (Vrep) and amplification factors (Gamp) is defined in a coordination relationship storage section. A search section searches an amplification factor (Gamp) and an actual result sound volume value (Vrep) coordinated with the requested sound volume value (Vreq) received from the remote controller from within the coordination relationship storage section. A sound volume control section controls the potentiometer based on a result of the search of the amplification factor. A responding section sends back the actual result sound volume value to the remote controller.