Spatial Audio Empowered Smart speakers with Xblock - A Pose-Adaptive Crosstalk Cancellation Algorithm for Free-moving Users

Smart IoT Speakers, while connected over a network, currently only produce sounds that come directly from the individual devices. We envision a future where smart speakers collaboratively produce a fabric of spatial audio, capable of perceptually placing sound in a range of locations in physical space. This could provide audio cues in homes, offices and public spaces that are flexibly linked to various positions. The perception of spatialized audio relies on binaural cues, especially the time difference and the level difference of incident sound at a user's left and right ears. Traditional stereo speakers cannot create the spatialization perception for a user when playing binaural audio due to auditory crosstalk, as each ear hears a combination of both speaker outputs. We present Xblock, a novel time-domain pose-adaptive crosstalk cancellation technique that creates a spatial audio perception over a pair of speakers using knowledge of the user's head pose and speaker positions. We build a prototype smart speaker IoT system empowered by Xblock, explore the effectiveness of Xblock through signal analysis, and discuss future perceptual user studies and future work.