Dynamic measurements of wind turbine acoustic signals, employing sound quality engineering methods considering the time and frequency sensitivities of human perception

A set of binaural time-recordings and analyses of wind turbine noise outside and inside a residence in Huron County, Michigan, made over two days and the intervening night in December 2009, is presented, centering on analysis at the time/frequency resolutions of human hearing according to the well-established practices of sound quality engineering and Soundscaping [1]. The purpose of this paper is to present wind turbine acoustic measurements at these timefrequency scalings and to suggest that such consideration, frequently neglected in favor of frequency resolution and long-term level averages, could augment the perceptually inappropriate averages (often A-weighted) typically taken over much longer intervals. The authors maintain that most measurements of wind turbines up to now have not considered, or not adequately considered, these signals’ very complex and varying behaviors at the time/bandwidth scalings of human perception. Although treating wind turbine noise aspects at all relevant frequencies, this paper will concentrate on low-frequency information.