A Study of Repeatability of Noise Measurements at Motor Vehicle Test Sites

The sound pressure level (SPL) measured at a given point varies as a motor vehicle goes through a pass-by noise test such as SAE J986a. The tests described in this paper were intended to assess the magnitude and variability of different motor vehicle noise measurements. All factors which might cause variation in the received SPL were either controlled or monitored. This study was designed to quantify the effects on SPL from wind turbulence.