Abstract: To improve upon a method of adjusting at least one filter parameter such as the mid-frequency of at least one filter unit provided with a playback system for audio signals, this filter unit being provided in particular for at least one digital equalizer assigned to the playback system, as well as an associated playback system so as to achieve automatic optimization of an acoustically correct bass level boosting, [a] first the acoustic frequency response is determined, [b] then a cutoff frequency below which the sound pressure falls below a sound pressure threshold level based on the average sound pressure is determined, and [c] next the filter parameter(s) of the filter unit is/are adjusted automatically, so that the mid-frequency of the filter unit is just above the cutoff frequency thus determined.

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 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.

Abstract: To improve upon a method of adjusting at least one filter parameter such as the mid-frequency of at least one filter unit provided with a playback system for audio signals, this filter unit being provided in particular for at least one digital equalizer assigned to the playback system, as well as an associated playback system so as to achieve automatic optimization of an acoustically correct bass level boosting,

Abstract: A method of acoustically correct boosting of the bass level of a playback system for audio signals by adjusting at least one filter parameter of at least one bass-boosting filter unit which is provided for the playback system and is assigned in particular to at least one digital equalizer that is provided with the playback system so that excessive boosting of bass level is prevented is described. This involves adjusting at least one filter parameter of the bass-boosting filter unit so that the boost in the bass level is reduced with an increase in the cut-off frequency and/or with an increase in the mid-frequency of the bass-boosting filter unit such that the isophones in the remaining reproducible bass frequency range are not exceeded.

Abstract: A method and an arrangement for reproducing a stereophonic or multi-channel audio signal in a space, particularly in the passenger compartment of a motor vehicle, is described Loudspeakers for reproducing acoustic signals are arranged at a plurality of positions in the space, and an amplitude and phase of the acoustic signals radiated from each loudspeaker are influenced so that wave fronts of the acoustic signals radiated by the loudspeakers overlap to form at least one first resulting wave front for a left channel and a second resulting wave front for a right channel of the stereophonic audio signal, so that the resulting wave fronts intersect in a listening zone within the space, and yield a stereo aural impression inside the listening zone.