The measurement of the middle ear transfer function usually requires
invasive methods. An equivalent analog equivalent model enables us
to evaluate its characteristics without damaging any part of the
ear. A linear and a nonlinear model of the middle ear have been developed
to predict intracochlear pressure and the stapes volume velocity
for various sound pressure levels (SPL). The linear model results
have been compared with human eardrum impedance and middle ear transfer
function data. The nonlinear phenomena due to the contraction of
the stapedius muscle over 80 dB and to the stapes clipping displacement
above 120 dB are represented by a set of variable electrical components.
The model of the acoustic reﬂex is based on experimental observations.
The study of the annular ligament behavior was performed on cats
and extrapolated to humans with some hypothetical restrictions. These
approximations provide information on the middle ear transfer function
and enable us to better understand the nonlinear middle ear mechanisms
in an intense