Spectrally equivalent artificial reconstruction of a historical church bell as a characterized acoustic source for in-situ soundscape studies

Historical soundscapes are often difficult to investigate experimentally because the acoustic sources that once shaped them have been removed, replaced, damaged, or are no longer usable under controlled conditions. This study proposes a digital metrological procedure for constructing a synthetic church-bell sound as a reference acoustic signal with known spectral characteristics compatible with those of a real historical source. An in-situ recording of a thirteenth-century bell from the Cathedral of Salerno was used as case study. The recorded signal was processed to reduce environmental noise, identify bell strikes, extract dominant spectral components, estimate the temporal decay, and generate a spectrally equivalent artificial signal through tonal synthesis. The comparison between the denoised recording and the reconstructed signal showed strong correspondence in terms of strike sequence, dominant tonal peaks, and decay behaviour. The resulting signal is not intended only as an audio replica, but as a characterized acoustic source that can be integrated into in-situ measurement chains for soundscape studies. The approach provides a bridge between hard metrology and soft metrology: a physically controlled sound event can be used to investigate how historically meaningful sounds may influence the perception, identity, and genius loci of cultural landscapes. By artificially reactivating the practice of sounding a bell, the method also addresses intangible heritage through measurable acoustic evidence. The results support future applications in acoustic heritage assessment, archaeological soundscape studies, cultural soundscape mapping, immersive interpretation, and digital-twin environments.