In this paper we present a novel enhancement to an existing music source separation algorithm which allows for a 76% decrease in computational load whilst enhancing its separation capabilities. The enhanced implementation is based on the ADRess (Azimuth Discrimination and Resynthesis) algorithm which performs a separation of sources within stereo music recordings based on the spatial audio cues created by source localization techniques. The ADRess algorithm employs gain scaling and phase cancellation techniques to isolate sources based on their position across the stereo field. Objective measures and subjective listening tests have shown the separation performance of the enhanced algorithm to be objectively and perceptually comparable with that of the original ADRess algorithm, whilst realizing a finer spatial resolution.