Pentatonic scale-based multidimensional psychoacoustic modelling of vehicle cabin audio quality

With development of intelligent cabin, specialized psychoacoustic evaluation method is needed to link subjective and objective parameters for audio quality design in vehicle cabins, in which traditional psychoacoustic metrics are limited in capturing multidimensional perceptual differences. This study proposes a pentatonic harmonic audio system evaluation (PHASE) framework to evaluate audio quality in vehicle cabins. The reverberation time and frequency responses were measured in five representative cars. The harmonic features were derived from the frequency responses based on the pentatonic scale. Six music clips were recorded in driver's and rear-right seats to generate ten sets (five driver's seat, four rear-right seats, and one baseline) of stimuli for evaluation. Subsequently, 50 participants evaluated audio quality for all stimuli on the 100-point scales across 9 dimensions: timbre brightness/darkness, timbre warmth/coolness, clarity, distortion, dynamic range, bass quality, spatial impression, localization, and distance. The evaluation models were established through multiple linear regression between the subjective rating values and harmonic features. These models showed strong explanatory power (R2 = 0.852 - 0.987) across all dimensions, effectively capturing multidimensional in-vehicle auditory perception. The PHASE framework demonstrates strong potential for evaluating audio quality in enclosed or irregular acoustic environments such as immersive virtual spaces and home theaters.