Temporal characteristics of heavy-weight floor impact sound insulation: In-situ reverberation estimation from the impact signal

This study investigates how temporal characteristics influence the evaluation of heavy-weight floor impact sound insulation, with particular attention to their relation to reverberant effects captured in the fast time-weighted maximum impact SPL, L_i,Fmax. Field measurements were conducted in 16 rooms across eight apartment units located in four vertically stacked buildings. The data were analyzed in two stages. Each signal was processed according to international standards to obtain L_i,Fmax^′, and a 10 ms RMS envelope was applied to derive temporal descriptors. The analysis showed that when reverberant energy persisted around the peak, reflected in longer transient durations and slower initial decays, the resulting impact levels increased in the low-frequency bands. These findings demonstrate that the influence of reverberant sound on L_i,Fmax can be effectively estimated directly from in-situ impact signals. To this end, three temporal indicators – transient duration, initial decay time, and the RMS-Fast maximum difference – were defined, providing a foundation for signal-based approaches to estimating reverberant effects in the evaluation of heavy-weight floor impact sound insulation performance.