Differences in subjective loudness and annoyance depending on the road traffic noise spectrum

There is at present no consensus about the relative importance of low frequency content in urban road traffic noise. The hypothesis underlying this research is that changes to different parts of the spectrum will have different effects depending on which part of the spectrum is subjectively dominant in any particular situation. This letter reports a simple listening experiment which demonstrates this effect using typical urban main road traffic noise in which the low frequency content is physically dominant without necessarily being subjectively dominant.