Methodology for Jury Evaluation and Target Setting for Passenger Vehicle Operational Sound Quality

In automotive market, with competitive car prices, build quality of a car will be a major distinguishing factor. Consumer's need for acoustic comfort has evolved from the removal of annoying noises to perceived sound quality. Operational sounds from electromechanical systems like sunroof system, window regulator, door lock system, HVAC etc. directly interact with users’ senses. The perceived acoustics comfort of these sounds are direct indicators of vehicle character and can influence customer’s buying decision. With the reduction in product development time and stringent cost constraints, a proper structured target setting methodology to benchmark & evaluate these operational sounds is crucial. In this paper, such a target setting methodology is proposed and discussed for operational sound quality evaluation. Electromechanical noises from various vehicles are measured using binaural head measurement system. Using Simultaneous Categorical Scaling method, jury evaluation is performed with advanced binaurally corrected headphones. Cluster analysis along with Multivariate Linear Regression is performed to understand correlation between jury ratings and psychoacoustic metrics. Sound Preference Index (SPI) is derived based on the correlated psychoacoustic metrics. Using SPI, psychoacoustic metrics targets are derived to meet project requirements.