The mechanical features of the voice coil,both static and dynamic,are introduced generously in other reviews concerning magnetic paths with magnetofluid. When studying the motion of the voice coil in magnetic paths or circuits containing magnetofluid,magnetofluid is considered generally as incompressible and viscous,that is the Newtonian fluid. However,it may perform non- Newtonian characteristics when the magnetic field strength is high,the viscosity is low and the magnetic particles are of a certain range...