Distortion of interaural time cues by directional noise reduction systems in modern digital hearing aids

In this paper we analyze the distortion of interaural time information by modern digital hearing aids. It is shown that the directionality in dual microphone hearing aids, created by a software directional microphone or an adaptive directional microphone, are very sensitive to intermicrophone mismatch, which in particular results in severe distortion of interaural time information. This interaural information is crucial for sound localization as well as for speech perception in noise.