Speaker
Description
Accurate spatial audio reproduction is increasingly important in automotive applications such as navigation guidance, advanced driver-assistance systems, and immersive entertainment. This study compares sound source localization performance in a vehicle cabin and an ITU-R BS.775-4 compliant multichannel reference listening room to assess whether the latter can serve as a suitable environment for preliminary spatial-audio tuning and verification. Two listening tasks were conducted with 32 participants (16 per environment): angular localization and distance-movement identification. Test stimuli consisted of a navigation speech prompt and a Park Distance Control (PDC) warning chirp. Angular localization performance was comparable in both environments, with 77% and 67% of responses falling within ±20° of the target direction in the reference room and vehicle cabin, respectively, while median localization errors remained nearly identical (11° and 12°). The vehicle exhibited an additional front-left localization bias associated with the asymmetric listening position and loudspeaker arrangement. Distance-movement identification proved substantially less robust than angular localization in both environments. Near-field sources moving away from the listener were frequently perceived as stationary, whereas far-field away movements were identified with high accuracy. Similar response patterns observed in both environments suggest that these limitations arise primarily from perceptual characteristics of auditory distance perception rather than from the vehicle cabin itself. The results indicate that a reference listening room can provide useful preliminary indications of localization performance and perceptual trends, while final validation remains necessary in the target vehicle environment to assess absolute performance and placement-dependent effects.