This paper researched on four different types cars, analyzing interior noise at the same speed under different points, the same point different speeds and the same car different speed different points, it is concluded that family car interior noise distribution law; Through analysis noise spectrum curve which can get the main frequency band, that may provide theoretical basis for automotive noise reduction. In addition, this paper gets that medium low-frequency noise(0-2Brk) are the biggest to composition car’s characteristics loudness from research on characteristic loudness curve, and with speed continuously improve characteristic loudness growth is very significant.
