Correlation Research Between Subjective Evaluation And Objective Parameters Of Car Interior Sound Quality

The concept of sound quality originated from automobile industry in America and Europe during the1980s, beginning with a sound quality of the products and then gradually developed and applied to aviation, railways, transportation, living environment, and other fields. The research and application of sound quality has become a new hotspot in noise control field. Many research institutions and universities at home and abroad have carried out related targeted research about sound quality. The car interior noise is controlled using the A weighted sound pressure level as the standard at present, but this standard can’t meet the demand of passengers in the car environmental acoustics already because it has some drawback. There is a need to establish a new evaluation standard to improve the interior noise environment. Because the sound quality can give passengers better subjective response for the interior noise, it has been gradually introduced and came into application. Within the noise limit, it is becoming a trend for the development of car interior noise design to use the sound quality evaluation system to carry out the research.This paper detailed expounds the definition of sound quality, meaning and its development. To introduce the sound quality evaluation parameters and corresponding mathematical model based on the psychoacoustic theory foundation. Combining with the actual conditions, test the interior noise, extract acoustic quality related parameters. And use the noise and vibration control analysis software to analysis the acoustical characteristics of noise signal, studied and analyzed the distribution rule of car interior noise. Basing on the summary analysis of the sound quality subjective evaluation experiment common method, experimental process and data post-processing methods, use the paired comparison method to carry out the subjective evaluation experiment with the12voice signals coming from the different car which was gathered with the different speed and analysis the correlativity between the subjective evaluation results and the objective parameters. Through the regression analysis, we establish a mathematical model which has two psychoacoustics objective parameters-loudness and sharpness and to validate the obtained model and then to have an exploratory research of the application of sound quality. Put forward the concept of relatively preference level and use it to set up the standard of the sound samples. After the analysis the relationship between frequency and the preference level, we find the frequency ranges that affect the sound quality which can provide reference for the improvement of sound quality.