Green Speaker Design (Part 1: Optimal Use of System Resources)

Increasing the efficiency and voltage sensitivity of the electro-acoustical conversion is the key to modern audio devices generating the required sound output with minimum size, weight, cost and energy. Traditional loudspeaker design sacrifices efficiency for sound quality. 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 paper presents a new design concept for active loudspeaker system that uses the new degree of freedom provided by DSP for exploiting a nonlinear motor topology, a soft suspension and modal vibration in the diaphragm, panel and in the acoustical systems.

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