A psychoacoustical study of wind buffeting noise

• We studied the unpleasantness of wind buffeting noise.
• A specific module in a wind tunnel experimentally generated wind buffeting.
• We conducted psychoacoustic experiments (real and equalized loudness).
• Unpleasantness is mostly correlated with loudness and fluctuation strength.
• We propose an indicator of sound quality for wind buffeting noise.

Aerodynamic noise resulting from a vehicle moving through air at high speeds is one of the most important sources of noise perceived by the passengers. It consists of a stationary broadband signal and of modulated and fluctuating components, particularly emphasized by gusts of wind and turbulences generated by the interaction with nearby vehicles. The article reports on a study of the perception of this latter phenomenon, wind buffeting, potentially deleterious to the sound quality of a vehicle. Binaural recordings of nineteen cars were conducted in a wind tunnel with a specific module designed to simulate mild or severe buffeting. Naive and expert participants first rated the unpleasantness of the recordings played at their real levels. There were large differences of loudness between the sounds resulting mostly from the car designs, and loudness was the main factor contributing to the unpleasantness of the sounds. Participants then rated the unpleasantness of the recordings equalized to the same loudness. In that case, unpleasantness was mostly influenced by the buffeting module and related to fluctuation strength, a psychoacoustical descriptor of perceived loudness modulations. We propose an indicator of the unpleasantness of wind buffeting based on fluctuation strength in several frequency bands as well as other descriptors of the spectral balance of the sounds.