Individual Listening Zone with Frequency-Dependent Trim of Measured Impulse Responses

Acoustic Contrast Control (ACC) has been widely used to achieve individual audio delivery in shared environments. The effectiveness of this method is reduced when the control is performed in reverberant environments. Even if control filters are computed using measured transfer functions, the robustness of the system is affected by the presence of reverberation in the plant matrix. In this paper a new optimization method is presented to improve the ACC algorithm by applying a frequency-dependent windowing of the measured impulse response used for the filter computation, thus removing late reflections. The effects of this impulse response optimization are presented by means of sound zoning results obtained from experimental measurements performed in a car cabin.