Contribution
Restoring Spatial Hearing in Active Noise Control Headphones
* Presenting author
Abstract:
Active Noise Control headphones effectively reduce ambient noise but also environmental sounds. This can lead to a loss of situational awareness and pose safety risks. To address this issue, some headphones offer audio passthrough, which uses microphones to play back external sounds through the headphone speakers. This partially restores situational awareness but lacks the spatial cues necessary for accurate sound localization. Spatial hearing depends on the filtering effects of the ears, which vary depending on the direction of the sound source. These are obstructed when headphones cover the ears. This paper presents a system designed to restore spatial hearing in Active Noise Control headphones. It utilizes microphones on the outside of the headphones and the speech microphone. The system estimates sound source direction by analyzing the differences in time of arrival. Head-related transfer functions corresponding to the estimated direction are then applied to the audio signal. This recreates the natural filtering effects of the human ear, generating spatialized audio that conveys directional information to the listener. The spatially processed audio is then played back through the headphone speakers, effectively restoring spatial hearing. Localization tests demonstrate the system's effectiveness in restoring spatial hearing.