A control characteristics changing unit reads, from an EEPROM, various control parameters in an ANC electronic controller, which correspond to specification information acquired from ECUs. The control characteristics changing unit then outputs control parameters, depending on changed specification information among the read control parameters, as change signals Sm1 through Sm6 to a basic signal generating unit, reference signal generating units, filter coefficient updating units, corrective signal generating units, switches, and variable-gain amplifiers, respectively.