Abstract: A method is proposed for automatically adjusting the filter parameters—center frequency, quality and amplification or attenuation—of at least one digital equalizer which is a component of a reproduction device for audio signals in a vehicle passenger compartment. To that end, first of all, the acoustical frequency response of the passenger compartment is ascertained. The inadequacies in the acoustics of the passenger compartment in the form of local maxima and minima in the measured frequency response are then determined. On this basis, the filter parameters are adjusted automatically so that at least a portion of these inadequacies is compensated. A reproduction device for audio signals for implementing this method is also proposed.

Abstract: A method is proposed that is used for activating the functions of an electrical device, preferably a car radio. A test routine stored in a storage area allocated to the device is executed by a control unit of the electrical device. The control unit activates at least one function of the electrical device on the basis of control commands predefined in the test routine. Information about the function just activated is reproduced on a reproducing device of the electrical device.

Abstract: A method is proposed for automatically adjusting the filter parameters—center frequency, quality and amplification or attenuation—of at least one digital equalizer (6,7) which is a component of a reproduction device (1) for audio signals in a vehicle passenger compartment.