Patent attributes
A speaker array, includes a plurality of speakers which are linearly arranged at a predetermined interval; and one-dimensional digital filters which are provided to correspond to the speakers respectively, in which predetermined filter coefficients are set previously, and which apply a filtering process to input sound data in response to the filter coefficients to output. Sound data derived by applying a digital conversion to input sound signals are supplied to respective one-dimensional digital filters. Sound signals derived by applying an analog conversion to the sound data output from respective one-dimensional digital filters are supplied to corresponding speakers to output a sound in response to the sound signals. The filter coefficients set in respective one-dimensional digital filters give an amplitude characteristic to a two-dimensional digital filter such that, when a frequency characteristic of the two-dimensional digital filter constructed by respective one-dimensional digital filters is represented by a two-dimensional frequency plane, a plurality of ripples are provided in a stop band in a section in a spatial frequency direction and also an amplitude of ripples in a non-physical area out of a plurality of ripples is larger than an amplitude of ripples in a physical area.
