Combined assessment of auditory distance perception and externalization

Area of Science:

• Virtual Reality
• Auditory Perception
• Human-Computer Interaction

Background:

• Auditory distance perception (ADP) and sound externalization are crucial for immersive virtual audio-visual environments.
• Understanding how acoustic and visual factors influence these perceptions is key for realistic VR experiences.

Purpose of the Study:

• To investigate frontal auditory distance perception (ADP) and externalization in virtual environments.
• To analyze the effects of headphone rendering, room size, reverberation, and visual room representation on auditory perception.

Main Methods:

• Utilized head-related impulse responses (artificial head or spherical model) for diotic and binaural headphone auralizations with/without head tracking.
• Employed a game engine for head-mounted display visuals, simulating two room sizes and an infinite space with varying acoustics.
• Investigated the impact of a movable virtual loudspeaker for distance indication.

Main Results:

• Room size significantly affected both ADP and externalization.
• Room visibility strongly influenced ADP, causing overestimations without visual cues.
• Reverberation and headphone rendering method significantly impacted externalization, with longer reverberation improving it.
• A movable virtual loudspeaker enhanced distance estimation accuracy.

Conclusions:

• Auditory distance perception and externalization are influenced by distinct factors in virtual environments.
• Visual cues are vital for accurate distance perception, while reverberation and rendering affect externalization.
• Distance estimation can be largely independent of perceived externalization, even for nearby sounds.