Effects of incongruent auditory and visual room-related cues on sound externalization

Sounds presented via headphones are typically perceived inside the head. However, the illusion of a sound source located out in space away from the listener’s head can be generated with binaural headphone-based auralization systems by convolving anechoic sound signals with a binaural room impulse response (BRIR) measured with miniature microphones placed in the listener’s ear canals. Sound externalization of such virtual sounds can be very convincing and robust but there have been reports that the illusion might break down when the listening environment differs from the room in which the BRIRs were recorded [1,2,3]. This may be due to incongruent auditory cues between the recording and playback room during sound reproduction [2]. Alternatively, an expectation effect caused by the visual impression of the room may affect the position of the perceived auditory image [3]. Here, we systematically investigated whether incongruent auditory and visual roomrelated cues affected sound externalization in terms of perceived distance, azimuthal localization, and compactness.