Churches offer an extreme example of the multipurpose space. Churches have several conflicting acoustical requirements during the same event. The acoustics during the service can’t be altered to meet the acoustical requirements both for organ and choir on one hand, and speech intelligibility, on the other. The differences are huge. Though these differences vary widely in their acoustical requirements, they share one fundamental acoustical requirement: silence, the elimination of background noise.

Furthermore, there are severe aesthetic constraints on church design. Architectural acoustics has to integrate into architecture. For example, flying panels are an excellent tool for reconciling reverberation and clarity, yet church committees may be reluctant to consider such visible measures. An excellent example flying panels (sails) in a sanctuary is provided by Holy Spirit Church in Lancaster, Pennsylvania. These panels serve not only their acoustical function of providing clarity within a reverberant sanctuary, but also enhance the visual sense of space in the sanctuary: architecure plus acoustics equals architectural acoustics.

One excellent model for Protestant church design is the American Colonial Protestant church. These churches are modest in size, narrow, quiet, with side balconies. They work well for both speech and church music. Contemporary church design would benefit a great deal from careful study of these paradigms.

Most churches require a sound system that is really integrated into the acoustics of the sanctuary.