Abstract: A control system is provided for controlling a transducer array. The control system includes a plurality of sparse filters and integrators. The control system can be used to separate signals from a plurality of sources or to generate complex signal patterns that combine and map to different spatial regions.

Abstract: The invention relates to a method of determining an impedance function IF of a load LS driven by an amplifier AM, said method comprising the steps of providing a digital audio signal DAS to said amplifier AM, measuring one of either a current signal representation CSR of current provided to said load LS by said amplifier AM or a voltage signal representation VSR of voltage provided to said load LS by said amplifier AM, determining a digital signal representation DSR on the basis of said digital audio signal DAS, and determining said impedance function IF of said load LS on the basis of said digital signal representation DSR and said measured one of either said current signal representation CSR or said voltage signal representation VSR.