A laboratory listening experiment on subjective and objective rating of impact sound insulation of concrete floors

A listening experiment on the associations between single-number quantities (SNQs) of impact sound insulation and subjective rating of impact sounds was conducted. The experiment was participated by 55 subjects in order to rate subjectively 44 sounds which were recordings of five actual impact sound sources directed to nine floor types. Eight objective SNQs were calculated for the floor types. A correlation analysis between the objective SNQs and subjective annoyance or loudness was carried out. The best indicators of subjective loudness regarding walking with hard-heeled and soft-heeled shoes and chair moving were L'n,w + CII, L'n,w + CI,50-2500 and the SNQ developed by Gerretsen. Concerning subjective annoyance of these sound types, the best predictors were L'n,w + CI,50-2500 and the SNQ developed by Bodlund. The best SNQ for explaining both loudness and annoyance was L'n,w + CI,50-2500. The subjective ratings of walking with socks and superball bouncing were weakly correlated with the SNQs. The results give some support the extension of the measured frequency range in objective rating of impact sound insulation of concrete floors to 50 Hz. There is nevertheless a need for the development of new SNQs which would correlate better with all general sound types.