If wind energy converters are located anywhere near a residential area, they must never become too noisy even in high winds. Most such power units try to go easy on their neighbors' ears, but even the most careful design cannot prevent noise from arising at times: One source is the motion of the rotor blades, another is the cogwheels that produce vibrations in the gearbox. These are relayed to the tower of the wind turbine, where they are emitted across a wide area - and what the residents hear is a humming noise. ...In a joint project with colleagues from Schirmer GmbH, ESM Energie- and Schwingungstechnik Mitsch GmbH and the Dr. Ziegler engineering office, IWU researchers have developed an active damping system for wind turbines. The project is being funded by the Deutsche Bundesstiftung Umwelt.

Bolton explained the many ways wind developers methodology is flawed. Field measurements are not done correctly (i.e. - improper microphone placement, no justification for sampling sites, etc.); accurate samplings need to be done for a full year to account for seasonal variations, but aren't; and computer prediction models wind developers rely on are inadequate because they don't account for modulation, coherence, refraction, and icing. Facts contained in Perry's DEIS from the sound study done by Horizon for Perry were brought up that highlighted Bolton's point that sound studies being done are totally inadequate: ...In response to questions asking what he thought of being "surrounded" by up to 23 turbines within 1.5 miles of their homes, he answered, "I would be VERY concerned if I were you."