Green Speaker Design (Part 2: Optimal Use of Transducer Resources)

Green speaker design is a new concept for developing active loudspeaker systems that generate the desired sound output with minimum size, weight, cost and energy. This paper focuses on the optimization of the transducer by exploiting the new opportunities provided by digital signal processing. Nonlinear adaptive control can compensate for the undesired signal distortion, protect the transducer against overload, stabilize the voice coil position and cope with time varying properties of the suspension. The transducer has to provide maximum efficiency of the electro-acoustical conversion and sufficient voltage sensitivity to cope with the amplifier limitations. The potential of the new concept is illustrated using a transducer intended for automotive application.

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