Abstract: A hearing aid for a person with asymmetric hearing perception (a weaker ear system and a better ear system) employs conventional frequency-selective amplification (26L) of sound coming to the weaker ear's system and frequency selective amplitude adjustment (32) and arrival time adjustment (retardation or relative advancement) (34) of sound coming to the better ear's system so that its resultant characteristics match those of the weaker ear's system, as aided, or even without aiding the weaker ear's system. As a result, sound perceived by both ear systems is matched or balanced, at each frequency, in both arrival time and amplitude. Such interaural balancing effects a great improvement in the binural processing mechanism, which in turn increases speech perception, especially in the presence of general noise or adjacent localized noise sources. The aid may be implemented by a pair of microphones (24L, 24R), one for each ear's system.