A preliminary investigation on the sound field properties in the Sagrada Familia Basilica

This paper reports on a preliminary investigation of the sound field properties inside a large Roman Catholic Church in Barcelona, the Sagrada Familia Basilica, which is a world heritage site although its construction has not been completed. The impulse responses were measured at five sound source positions combined with 14 measurement locations inside the Sagrada Familia Basilica, and the Impulse response to Noise Ratio (INR) were examined to examine the reliability of the measured impulse responses. The room acoustic parameters were calculated and the following five sound field properties in the Sagrada Familia Basilica were analysed: reverberation, spaciousness, loudness, warmth and clarity. The reverberation time (T20) and the Early Decay Time (EDT) were compared with the existing optimal values for small volume churches whereas the middle frequency strength of sound (Gmid), the low frequency strength of sound (G125), the clarity (C80) and the binaural quality index (1 - IACCE) were compared with the optimal values for concert halls. The understanding of the sound field properties in churches, especially in a church of such a large volume as the Sagrada Familia Basilica, is still an open topic and much further research is necessary for a more thorough understanding.