Buratti C., Mariani R., Costarelli I.

Indoor acoustic comfort is very important because it allows to have a good intelligibility of the acoustic message, intended as talking language and as music. In the present paper a case study of a church is investigated; the church (about 9.000 m3 volume) is situated in Perugia (Umbria) and it was built in 1993, so it is a modern building. Materials used in the church (such as marble on the floor, wood on the ceiling, etc) give no good acoustic performances, especially on speech intelligibility. A measurement campaign was carried out, in order to evaluate the main acoustic parameters in the current situation and to propose a corrective solution. Many measurements were carried out, in different points: reverberation time T60, RASTI, STI, clarity C80, definition D. Results show that the church has no good acoustic behaviour, especially due to the too high reverberation time values; also the other acoustic quality indexes are far from the optimal ones. So an acoustic correction of the church is proposed: the optimal values of the acoustic parameters were considered and a simulation of the acoustic behaviour was made by the calculation programme “Ramsete”; then the design of acoustic correction solutions was proposed.