Abstract

Loudspeaker models are getting more complex and try to model more occurring physical effects. One of these effects is viscoelastic creep which affects polymers of the loudspeaker suspension. The excursion of the membrane gets time and frequency dependent and an increase of the excursion at low frequencies occurs. This can lead to problems especially in microspeakers due to place limitations and the lack of a spider. Models considering creep usually work in frequency domain and therefore are restricted to linearity. To be able to consider nonlinearities like the force-factor BL we make our calculations in time domain. We start with a traditional loudspeaker model and replace the spring with a Standard Linear Solid model to describe the viscoelastic creep. Then we send stepped sine excitations into the system, calculate the differential equation and solve it numerically with the MATLAB ode-solver. After calculating the maximum excitation in steady state we can observe the increase at low frequencies. This concept can be improved and expanded upon further.

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