A system and method for improving sound quality for subjects with impaired hearing by applying a lowpass filter and a set of mid- to high-frequency narrowband filters to a signal. A set of narrowband filters are applied to sounds so that the impaired ear is stimulated to respond in a manner more similar to that of a healthy ear at low to moderate sound levels, for which intelligibility is high. Information falling outside of the set of narrowband filters is 'discarded' or filtered out, which preserves the representation of the information in the narrowbands. Because energy at frequencies between the narrowband filters is discarded, the sound spectrum is significantly changed, resulting in a clearer sound that is more natural and higher in intelligibility than conventional sounds or sound processing techniques.
Physiologically-Based Signal Processing System and Method