Improving In-vehicle Sound Quality Under The Accelerating Conditions

This paper by reading a large number of documents and materials, and combining the sound quality research results at home and abroad, I, carried out the collective experiments about the stale inside the car under the accelerating conditions. And this text set up subjective evaluation of sound quality model by psychoacoustic objective parameters. The passive noise control experiment specific to the worst noise sample was conducted, and through the comparison, the in-vehicle sound quality has got obvious improvement after optimization.The paper has introduced psychoacoustics of the basic theory at first, Sound quality evaluation and analysis also were studied. The point is to explore the objective assessment parameters of psychology and non-psychology acoustics and comprehensive evaluation index, especially the influence on subjective evaluation of sound quality under the accelerating conditions. And at the same time the calculation method of parameters were introduced.The articles studied the method of sound quality subjective evaluation based on the test condition environment and the acquire sound samples. In the test design,24 in-vehicle noise samples were acquired from 8 vehicles of various types separately. And the analysis software has been carried on objective analysis to the noise samples, obtain loudness, sharpness, shake degree, roughness, definition index, etc. curve graph of parameter.This text play backs the noise signal to appraise and test on the basis of commenting on objectively for the selected subjective estimator, appraising methods adopt intensity classification to combine with comparative method in pairs. Obtain the relevance between the subjective assessment results and the objective physical quantity to set up the subjective model of commenting on mathematics and analyzing which has accelerated the sonority under the state clearly, sharpness, shake degree and roughness influence the main factor of a time of quality in the car. Through subjective and objective analysis, I have put forward the scheme of improving the noise of vehicle optimally based on sound quality.On the basis of preliminary design, we have used method of passive noise control to test the NO.7car. Adjust an engine mount system to the Stiffness of mountings,to compare the experiments.The parameters of the noise all have been reduced in the car.subjective comment after optimizing at the same time.The result indicates that the grade of appraising has risen to 16 from 12.Thus it has not merely proved the correctness of that comments on analyzing the model of mathematics subjectively, It also prove to everyone that the noise passive control method can enhance in-vehicle sound quality effectively under the acceleration conditions.