Assessment of sound source localization of an intra-aural audio wearable device for audio augmented reality applications

Abstract

This paper presents a study on the effect of an intra-aural Audio Wearable Device (AWD) on sound source localization. The AWD used in this study is equipped with a miniature outer-ear microphone, a miniature digital signal processor and a miniature internal loudspeaker in addition to other electronics. It is aimed for audio augmented reality applications, for example to play 3D audio sounds and stimuli while keeping the wearer protected from loud or unwanted ambient noise. This AWD is evaluated in terms of ambient source localization using three localization cues computed using signals played from different positions in the horizontal and sagittal planes and recorded in the ear canals of an artificial head with and without a pair of AWDs. The localization cues are: the inter-aural time difference, the inter-aural level difference, and the head related transfer functions. Results showed that the used AWD does barely affect the localization of low frequency sounds with localization error around 2°, and only affects the localization of higher frequency sound depending on their position and frequency range.