Abstract

An active noise reduction system (2) comprising an electroacoustic plasma transducer (5) for mounting in an installation structure and an acoustic sensing system (11). The electroacoustic plasma transducer comprises a plasma electrode arrangement (6) including a collector electrode (8) and a corona electrode (9), and a control system (7) connected to the plasma electrode arrangement for supplying power to the plasma electrode arrangement. The control system comprises a controller (12), and a amplification circuit (13). The acoustic sensing system is connected to the control system providing a measurement signal of an environmental sound to control the output of the electroacoustic transducer for reducing noise. The control system comprises a filter implementing a control transfer function θ(ω) based on a model of the electroacoustic plasma transducer.

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