A flow cytometry apparatus and methods to process information incident to particles or cells entrained in a sheath fluid stream allowing assessment, differentiation, assignment, and separation of such particles or cells even at high rates of speed. A first signal processor individually or in combination with at least one additional signal processor for applying compensation transformation on data from a signal. Compensation transformation can involve complex operations on data from at least one signal to compensate for one or numerous operating parameters. Compensated parameters can be returned to the first signal processor for provide information upon which to define and differentiate particles from one another.