Simulation and measurement of loudspeaker nonlinearity with a broad-band noise excitation

Andrzej Dobrucki (1) , Rafal Siczek

1 Wroclaw University of Science and Technology

In the paper the method of measurement of nonlinear distortion using broad-band signal as the excitation is presented. It consists in excitation of loudspeaker with an intensive broad-band noise with removed narrow frequency band using band-stop filter. The acoustic signal produced by the loudspeaker is filtered with a band-pass filter with the same bandwidth as previously removed. The content of signal in this frequency band is a measure of nonlinear distortion. The measurement can be realized in successive frequency bands in order to obtain the distortion as function of frequency. The very high steepness of slopes in band-stop and band-pass filters is required. The filters can be realized with a digital technology. Using Simulink software the measurement of actual loudspeakers as well as simulations can be conducted. In the paper the influence of nonlinear parameters: stiffness of suspensions, force factor and inductance are presented and the results of measurements as well.

Mots clés: Loudspeaker; Nonlinearity; Noise

Domaines: Acoustique [physics.class-ph]

Andrzej Dobrucki, Rafal Siczek. Simulation and measurement of loudspeaker nonlinearity with a broad-band noise excitation. Acoustics 2012, Apr 2012, Nantes, France. ⟨hal-00811137⟩