This PAS applies to the suspension parts of electroacoustical transducers (for example,
loudspeakers). It defines the parameters and measurement method to determine the stiffness
of suspension parts like spiders, surrounds, diaphragms or cones before being assembled in
the transducer. The measurement results are needed for engineering design purposes and for
quality control. Furthermore, this method is intended to improve the correlation of
measurements between suspension-part manufacturers and loudspeaker manufacturers.
The measurement method provides the effective stiffness, Keff, based on a linear model and
the variation of the stiffness, K(x), versus displacement x using a non-linear model. Both
parameters are measured dynamically by exciting the suspension part to mechanical
vibrations.