added ring modulation
added ring modulation

rcgilbert/csc344-wi14,rcgilbert/csc344-wi14,rcgilbert/csc344-wi14,rcgilbert/csc344-wi14,rcgilbert/csc344-wi14,rcgilbert/csc344-wi14,rcgilbert/csc344-wi14,rcgilbert/csc344-wi14,rcgilbert/csc344-wi14