Combination effects of tone and duration parameters on perceived noisiness. NASA CR-1283.

Abstract

Subjective judgment tests were conducted to determine the effects of variation in the tone content and stimulus duration upon the relative acceptability of sound stimuli consisting of shaped broad‐band noise with and without a 2000‐ or 4000‐Hz tone. Tone‐to‐noise ratios measured 25, 10, and 5 dB in 13‐oct bands. All stimuli were of triangular time patterns and included durations of 4, 12, and 32 sec. Tests were also conducted to investigate the effect of varying the time at which the level of the tone reached its maximum value relative to the time at which the level of the broadband noise reached its maximum value. Various measures were employed in the analysis of the judgment results; these included the over‐all sound‐pressure level (SPL), A‐weighted SPL, N‐weighted SPL, and perceived noise level with and without tone and duration corrections. The results of the tests indicate that the perceived noise level with tone and duration corrections provides better agreement with subjective judgments of acceptab...