The compliance of a moving coil loudspeaker is known to depend on the level of the input signal. This effect is visible as a drop in resonance frequency. A nonlinear frictional element with hysteresis, and thus a level dependent compliance and damping, is added to the standard lumped parameter model. A comparison of simulation results and measurements reveals that the frictional model is able to explain the nonlinear behavior seen in the measurements. The paper presents a scheme for fitting the model parameters to measured data. Results suggest that strong interaction between the frictional elements and the linear parameters is complicating this fitting, and strategies for solving this problem is presented and discussed
