Archives of Acoustics, 35, 1, pp. 49-66, 2010

Ranking of the nonlinearities of electrodynamic loudspeakers

Romain RAVAUD
Laboratoire d'Acoustique de l'Universite du Maine UMR CNRS 6613
France

Guy LEMARQUAND
Laboratoire d'Acoustique de l'Universite du Maine UMR CNRS 6613
France

Valérie LEMARQUAND
Laboratoire d'Acoustique de l'Universite du Maine UMR CNRS 6613
France

Tangi ROUSSEL
Laboratoire d'Acoustique de l'Universite du Maine UMR CNRS 6613
France

The aim of this paper is to present a way of ranking the nonlinearities of electrodynamic loudspeakers. For this purpose, we have constructed a nonlinear analytic model which takes into account the variations of the small signal parameters. The determination of these variations is based on a very precise measurement of the electrical impedance of the electrodynamic loudspeaker. First, we present the experimental method to identify the variations of these parameters, then we propose to study theoretically the importance of these nonlinearities according to the input level or the input frequency. We show that the parameter which creates most of the distortions is not always the same and depends mainly on both the input level and the input frequency. Such results can be very useful for optimization of electrodynamic loudspeakers.
Keywords: electrodynamic loudspeaker; nonlinearities; small signal parameters; nonlinear modeling
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Copyright © Polish Academy of Sciences & Institute of Fundamental Technological Research (IPPT PAN).

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