A vibratory separator (in one aspect, a shale shaker) and methods for using it, the separator in certain aspects having a base, a basket movably mounted on the base, screen apparatus on the basket, material flowing onto the screen apparatus for treatment, at least a portion of the screen apparatus not inclined downhill (e.g. said portion horizontal or uphill), electromagnetic vibratory apparatus connected to the basket for vibrating the basket and the screen apparatus, driving apparatus for driving the electromagnetic vibratory apparatus, and control apparatus (on-site and/or remote) for controlling the driving apparatus and the electromagnetic vibratory apparatus; the material, in one aspect, being drilling fluid material with solids therein.