Direct Estimation of Physical Parameters in Nonlinear Loudspeaker Models

Abstract

For better loudspeaker unit and loudspeaker system design, improvements of the traditional linear, low frequency model of the electro-dynamic loudspeaker are essential. In this paper a nonlinear loudspeaker model with suspension creep is introduced, and 6 physical parameters, including coefficients of a second order polynomial approximation of the dominating static nonlinearity, are estimated. A new sensitivity approach is used for input design and qualitative parameter accuracy evaluation, and the physical parameters are estimated directly by minimizing an output error. The results indicate that the model structure, as well as the applied sensitivity approach, is proficient, and that accurate parameter estimates are obtained.