Modelagem e simulação da dinâmica de alto-falantes em caixas acústicas seladas

Abstract

Loudspeakers are the main item in any high fidelity sound system, and are the main responsible for distortions in sound reproduction. The main reason for that is the presence of nonlinearities in their functioning. Recent studies strongly suggest that these nonlinear effects can lead the speaker to multiperiodic and chaotic behaviors. This implies in distortions since additional spurious frequencies are added to the original sound. However, those studies do not consider an important issue in real speaker usage, which is the acoustic enclosure in which it is usually installed in. The main goal of this work is to extend those mentioned studies taking this additional factor into consideration, and to verify what influence a limited enclosure can cause on speaker dynamics. The results suggest that the finite volume of the acoustic enclosure can strongly affect the fidelity of a loudspeaker, reducing the spurious multiperiodicity and chaos. As a general rule, smaller enclosures inhibits such spurious behaviours but, at the same time, diminishes the dynamical response of the loudspeaker. Therefore, a criterious volume choice should lead to the smaller possible volume however without sacrifying the loudspeaker musical dynamics.