Localization based on enhanced low frequency interaural level difference

TL;DR

This paper proposes replacing low-frequency interaural time differences with level differences using a new beamformer, improving localization in anechoic environments for normal-hearing listeners without affecting speech intelligibility.

Contribution

It introduces a novel beamforming method that enhances low-frequency interaural level differences by replacing inaudible time differences, addressing a key issue in hearing impairment.

Findings

Improved localization in anechoic scenes for normal-hearing listeners.

No significant impact on speech intelligibility.

Effective enhancement of low-frequency interaural level differences.

Abstract

The processing of low-frequency interaural time differences is found to be problematic among hearing-impaired people. The current generation of beamformers does not consider this deficiency. In an attempt to tackle this issue, we propose to replace the inaudible interaural time differences in the low-frequency region with the interaural level differences. In addition, a beamformer is introduced and analyzed, which enhances the low-frequency interaural level differences of the sound sources using a near-field transformation. The proposed beamforming problem is relaxed to a convex problem using semi-definite relaxation. The instrumental analysis suggests that the low-frequency interaural level differences are enhanced without hindering the provided intelligibility. A psychoacoustic localization test is done using a listening experiment, which suggests that the replacement of time differences into level differences improves the localization performance of normal-hearing listeners for an anechoic scene but not for a reverberant scene.