Quantifying the character of wind farm noise

Relatively low levels of wind turbine noise have been shown to cause annoyance, suggesting that the character of the noise is more important than its magnitude. This investigation focuses on the time-varying nature of wind farm noise measured outdoors in the vicinity of a wind farm at a number of residences. The time varying characteristics of the noise are quantified using a number of metrics available for detection and quantification of amplitude modulation. Several psycho-acoustic descriptors such as sharpness, loudness and roughness are also considered and the relevant parameters are quantified for noise measured near a wind farm. The results are compared to subjective descriptions that were recorded by residents living close to the measurement locations.