Abstract: A vibratory separator and methods for using it, the separator in certain aspects having a base, a basket on the base, motor apparatus for vibrating the basket and screen apparatus thereon, variable frequency drive apparatus for selectively driving the vibratory motor apparatus, and, in certain aspects, angle adjustment apparatus for adjusting angle of the basket; and, in certain aspects, for sensing a parameter indicative of operation of the vibratory separator, and control apparatus for receiving signals from the sensor apparatus, for controlling the separator based on said signals; and, in certain aspects, for automatically signalling a drive apparatus to change the speed of the motor apparatus; and, in certain aspects, the vibratory motor apparatus connectible to the basket at a plurality of locations so that a motion profile of the basket is selectively variable between linear, elliptical, and circular motion.