LAUSR

Abstract Acoustic studies were carried out in a dome-shaped sacral room of the Pentecostal Congregation in Katowice in Silesia, Poland. The investigated room is used for religious purposes, and in terms of acoustics it facilitates the propagation of speech and musical sounds. In the study, acoustic measurement methods were adopted to assess sound reverberation. The “in situ” method was used to determine sound decay curves, and reverberation time was determined in line with EN ISO 3382-1: 2009, EN ISO 3382-2: 2010. Participants of the services complained about poor reception conditions of verbal and musical sounds and flutter echo in some places of the room. Acoustic studies confirmed the listeners' impressions. The room had long reverberation time. To improve the acoustic parameters of the interior, the application of spray-deposited insulating material was proposed. The selected material was subjected to laboratory tests on sound-absorbing properties. The sound absorption coefficient of the material was determined as a frequency function. Then the material was applied on the inner surface of the dome. Acoustic measurements of the adapted interior were repeated. Based on the measurements, the STI was calculated. In effect, a significant improvement in reverberation conditions of the investigated interior was obtained.