Who am I speaking at? Perceiving the head orientation of speakers from acoustic cues alone

The ability of people, and of machines, to determine the position of a sound source in a room is well studied. The related ability to determine the orientation of a directed sound source, on the other hand, is not, but the few studies there are show people to be surprisingly skilled at it. This has bearing for studies of face-to-face interaction and of embodied spoken dialogue systems, as sound source orientation of a speaker is connected to the head pose of the speaker, which is meaningful in a number of ways. We describe in passing some preliminary findings that led us onto this line of investigation, and in detail a study in which we extend an experiment design intended to measure perception of gaze direction to test instead for perception of sound source orientation. The results corroborate those of previous studies, and further show that people are very good at performing this skill outside of studio conditions as well.