Analysis of Just Noticeable Difference and Annoyance by Octave band of Rubber ball Impact Sound using auditory perception experiment

This study investigated the Just Noticeable Difference (JND) and Annoyance in each octave band of impact source produced by rubber balls using an auditory perception experiment. Through a literature review, two representative spectra for the impact sounds of rubber balls were selected. Spectrum A represents the impact sound on a 210mm concrete slab, while Spectrum B represents the impact sound on 110 ~ 180mm concrete slabs. The source levels of the rubber ball impact sound used in the experiment were given as Single Number Quantities (SNQ) of 47, 51, and 55 dB. Additionally, variations of ±2, ±4, and ±6 dB were conducted for each octave band. The subjects' response data were analyzed using Probit regression analysis. The results showed that both Spectrum A and Spectrum B exhibited higher change rate of Annoyance in the frequency bands where the JND results were smaller. Specifically, these frequency bands were 63 and 125 Hz for Spectrum A, and 250 and 500 Hz for Spectrum B.