DETECTABILITY AND ANNOYANCE OF REPETITIVE IMPULSIVE SOUNDS

Psychoacoustic research on the audibility of trains of single cycle waveforms of varying fundamental frequency, repeated at varying repetition rates, revealed sizeable differences in broadband signal to noise ratios needed to support constant detection performance. These differences were related to the bandwidth of the hypothetical first stage auditory filter through which people listen for signals occurring in background noise. Implications of these findings for design of helicopter rotor systems to minimize detectability and community annoyance are discussed in the context of the psychophysical Theory of Signal Detectability.