Efterklangstid och ljudkrukor i Dalby kyrka : En studie av efterklangstiden på 1400-talet jämfört med nutid samt beskrivning av kopplingen mellan ljudkrukor och Helmholtzresonatorer

Sammanfattning: This study investigates the reverberation time in Dalby church. The reverberation time is analyzed with respect to contemporary conditions and the 15th century. The connection between ceramic pots and Helmholtz resonators (a kind of acoustic resonator) are investigated. In the ceiling in the church, holes are found which most likely are the opening of ceramic pots which is an important assumption for the thesis. In Swedish musicology, the relationship between ceramic pots and acoustic resonators is poorly documented. Similarly, there is limited scholarly discussion on reverberation time in churches from 15:th century compared to present time. Based on documentary evidence, the reverberation in Dalby church, was different in the 15:th century than it is today. The church interior was different from today and it has most likely contributed to a different absorption in the church. This study investigates how these circumstances altogether affected the reverberation time and discusses its possible implications for the performance of chant. This master´s dissertation is based on theoretical studies combined with practical measurements of the reverberation time in Dalby church and simulations of reverberation in soft ware program? Odeon in a 3D-model of the church. The following questions guided the work: What was the difference in reverberation time for Dalby church in 15:th century compared to present time and what effect does it have on chant? What´s the contribution from ceramic pots for the acoustic environment in the church? The rebuilding of the church during this period is taken into consideration. This also affects the volume of the church. A potential method on evaluation of ceramic pots was tested. Conclusions are: Reverberation time was shorter in church of Dalby in the 15:th century compared to present time.  The ceramic pots can potentially contribute to alterations of various frequencies and thus affect the performance of chant.