The acoustics of 16th-century Jesuit churches in Andalusia: Latin cross plans following the model of Il Gesù

• Acoustics in Jesuit ecclesiastical spaces after the Council of Trent (16th c.). • In situ measurements and modelling of three Jesuit churches inspired in Il Gesù. • Sources located in the high altar do not favour the perception of the sound field. • Receivers in tribunes improve the perception of the sound field. • The positions of the source under the transept dome are more favourable. Following the Council of Trent, profound changes were observed in ecclesiastical architectural space as a result of the new spirit infused into the Catholic Church by the Counter-Reformation. The Jesuit mother church, Il Gesù, contributed to the consolidation of the model of the single nave church, eliminating the aisles and reducing the size of the transept. This architectural model was disseminated in step with the expansion of the Society. The churches of Santa Catalina (Cordoba), La Anunciación (Seville), and La Encarnación (Marchena, Seville) provide emblematic examples of the model adopted by the Society of Jesus in the second half of the 16th century in Andalusia. The typological, geometric, and material similarities displayed by these churches enable a common analysis of the sound field, to be carried out through in-situ acoustic measurements and simulations. The study of different source positions in similar models enables the determination of the optimal source and receiver configurations. It was found that the position on the main altar, coinciding with the position of the priest in the Tridentine rite, does not facilitate the perception of the sound field, except in the positions in the high tribunes. When the source is under the dome of the transept, the sound field evaluation is more favourable. Conversely, a comparative analysis of churches considered to be ’twins’, St Catalina and La Anunciación, has shown the impact that the interior cladding of these spaces has on the perception of their sound field.