Acoustic Analysis of the Sacred Bell of King Seongdeok and the Utilization of Digital Sound Sources

Abstract. The Sacred Bell of King Seongdeok, cast in 771, is one of Korea’s most iconic cultural heritage artifacts, renowned for its elegant appearance and magnificent sound. To ensure its preservation, regular striking of the bell was discontinued in 1992. Since then, several scientific investigations have been conducted to accurately assess the bell’s condition and develop effective conservation strategies. The most recent investigation was an acoustic analysis carried out from 2020 to 2022. This study aimed to diagnose potential structural changes in the bell by comparing the results with those from an acoustic investigation conducted two decades earlier. Upon comparison, no changes were observed in the distribution of natural frequencies. Furthermore, there were no differences in beat duration or directionality—factors that are highly sensitive to even subtle structural changes—suggesting that no significant structural alterations have occurred, based on vibration and acoustic measurements. Alongside this diagnostic analysis, sound sources were recorded during the investigation in an effort to capture audio as close as possible to the bell’s original sound. The digitized sound data obtained through this process is now made publicly available in various formats, allowing the general public to listen to and experience the sound of the Sacred Bell.