Acoustics in Central-Plan Catholic Churches: The Jesuit Proposals in Andalusia During the 17th Century

During the Baroque period, centrally planned churches were widely promoted, particularly by the Society of Jesus, due to their symbolic and spatial qualities. In Andalusia, three representative examples of Jesuit centralised layouts were developed: San Hermenegildo, with an elliptical plan; Santo Cristo, with a circular layout; and San Luis, based on a Greek cross configuration. These churches share features such as lateral chapels integrated into thick walls or piers, upper tribunes ensuring visual and acoustic connection with the main space, and a dominant dome. The acoustic field was characterised through in situ measurements and validated acoustic simulations, considering multiple source positions and both empty and occupied conditions. Different source–receiver configurations were analysed to assess acoustic behaviour in centralised geometries. The results show that the elliptical plan of San Hermenegildo produces longer reverberation times and a more enveloping sound field, but reduced musical clarity and speech intelligibility. In contrast, Santo Cristo and San Luis exhibit improved acoustic performance, particularly when the source is located beneath the dome, where early reflections enhance clarity, definition and intelligibility. These findings highlight the influence of geometry, volume, dome configuration and source placement on acoustic perception in historical religious spaces.