A Novel Miniature Matrix Array Transducer System for Loudspeakers

Abstract

A breakthrough in novel loudspeaker design has been achieved using miniature actuators in a matrix configuration. Present flat-panel loudspeakers exploit resonant modes, whereas conventional cone-type loudspeakers use pistonic motion to reproduce sound. A new actuator has been designed so that it introduces pistonic motion in flat-panel loudspeakers. Instead of one or two exciters, the proposed panel speaker has numerous miniature transducers vibrating coherently to produce sound. In this device, the whole body vibration of the panel reduces the poor bass and impulse response associated with present flat-panel speakers. Frequency responses show that this novel transducer is suitable for loudspeaker application because of its linear and consistent output over the whole audible frequency range and for various excitation currents. Measurements on three different device configurations prove a moving magnet transducer to be the most suitable for loudspeaker application. Finite element modeling has been used to examine single transducer operation and the magnetic interaction between neighboring transducers in a matrix array format. Experimental results show the correct positioning of the transducers in a matrix configuration, as observed by the simulation, reduces the effects of interferences on the magnetic transducers. Also, results show that larger matrix array transducer speakers exhibit better low-frequency responses