a method of generating a composite signal in a closed loop servo signal system of a data recording system used to drive a recording head to any given position within a dynamic range of a servo tracks includes an optical pickup system for generating optical spots focused on a recording medium , the spots separated by equal distances across a track , the optical pickup system receiving a set of reflectances from the spots , a media system for providing the servo tracks responsive to optical spot illumination , an electric system for generating a set of filtered signals from the reflectances and for generating a set of s - curves by pair wise subtraction of the filtered signals , a processing system to generate a composite servo position signal from the s - curves and filtered reflectances , and a servo system for driving the recording head to a desired position by comparing the desired position to a measured position from the composite servo position .