This study investigates a method for presenting auditory distance in sound field reproduction using Higher-Order Ambisonics (HOA) and Near-Field Compensated HOA (NFC-HOA). With the continued development of virtual reality (VR) technologies, spatial audio techniques that improve immersion have attracted increasing attention. Although HOA and NFC-HOA point source rendering enable placement of virtual sources at arbitrary positions, conventional implementations based on free-field assumptions are limited in conveying distance for far-field sources. To address this limitation, this study focuses on the spatial rendering of reverberation, which serves as an important cue for auditory distance perception. The proposed method employs model-based reverberation synthesis, in which direct sound is rendered using NFC-HOA, early reflections using HOA, and late reverberation is simulated by exponentially decaying filtered white noise. To evaluate the proposed method, a perceptual experiment is conducted in which two sound sources are presented simultaneously from the same direction at different simulated distances. Virtual sources are reproduced using a 42-channel spherical loudspeaker array with a radius of 1.125 m. Experimental results are expected to contribute to the development of spatial sound field reproduction techniques with improved distance representation for immersive applications.
Akai et al. (Wed,) studied this question.