AES 5th International Conference on Automotive Audio

Several studies have shown that individual preferences with respect to frequency- and loudness-dependent amplification can differ markedly across listeners. To accommodate such individual preferences, sound personalization concepts have been proposed. This study investigates if differences in individually preferred settings across different audio systems can be predicted from measurable differences in acoustic transmission properties of the audio systems. Self-adjusted preference profiles of 20 normal-hearing listeners were measured for seven audio playback systems including automotive audio systems, a soundbar, and two types of headphones. The results indicate that, while interindividual preferences varied largely, there were systematic differences between audio systems which appeared to compensate acoustic differences, suggesting that future applications could benefit from known individual preference data in other playback systems to automatically adapt to an individual user’s needs.

As immersive object-based spatial audio continues to gain widespread adoption in the music industry, automobiles have become a target environment for multichannel audio reproduction capabilities. This emergence is driving new advances in audio rendering techniques. We present novel rendering strategies that scale with the number of available channels in automotive audio systems. This includes virtual height reproduction without the need for discrete overhead speakers that can be costly to implement. Here we compare the perceptual impact of 5.1 discrete, 5.1.4 discrete, and 5.1 virtual height rendering systems in multiple automotive environments. Subjective assessment paired comparison experiments were conducted to measure preference and multiple spatial audio attributes, and probability outcomes were modelled using a Bradley-Terry-Luce rank ordering. The 5.1 virtual height system provides a comparable sense of spaciousness and externalization to the 5.1.4 discrete channel system without degradation of spectral naturalness. These findings highlight the potential for virtual height rendering to enhance spatial audio immersion in automotive environments while minimizing the need for additional physical speakers. Further, this methodology can be generalized for subjective evaluation of audio delivery performance across a variety of channel configurations. We also describe multiple alternative rendering techniques for virtualization of immersive audio in automotive environments for future investigation.

Automotive manufacturers are engaging with audio system providers to offer unique auditory experiences. This is achieved through the replication of acoustic environments, coinciding with the growing prominence of infotainment systems. Gaining an understanding of how acoustical parameters impact human perception is of paramount importance in the development of virtual acoustic venues within this context. Hence, this is the initial study to explore the correlation between objective measures and subjective responses in the reproduced in-vehicle virtual acoustics, with the aim of augmenting the auditory experience for passengers. A jury test was conducted, and the resulting data was subjected to statistical analysis. The findings align with previous studies except for intimacy, indicating the visual disparities in virtual environments. Also, while reverberation, closely linked to envelopment, is basically influenced by early decay time, optimizing reverberation time within a specific range can improve the auditory experience in vehicles by naturality, which is correlated with key variables including overall impression.