When the Community of Christ wanted an ecumenical Peace Temple at their world headquarters in Independence, Missouri, they asked architect Gyo Obata to create a unique building with a shape inspired by nature. He drew on the chambered nautilus, creating a spiral that rose to a central spire.
The exterior shape is expressed within the 1,600 seat sanctuary with its concave walls and spiraling vaulted ceiling, which presented considerable acoustics challenges. Since many services are lightly attended, the seating bowl is divided into a main floor and a balcony, with control rooms and translation booths tucked under the balcony. The control room windows are angled in section to direct sound into the congregation. The walls behind the balcony are shaped into long-radius convex bows and built of split-face stone for bass support and high frequency diffusion.
To combat focusing off the spiraling ceiling, Kirkegaard took advantage of a large scale physical model that the architects had built of three bays of the spiral. Using a light source to simulate a sound source, we applied reflective mylar to models of various ceiling shapes until one was found that produced an even dappling of light on the main floor, free of concentrated stripes or hot spots. Balancing cost against bass response, the ceiling was constructed of gypsum board—triple layer for the large surfaces lower in the room, double layer for the surfaces higher in the room, and single layer at the very top of the spiral. The heavy stone walls behind the balconies compensate for the bass absorption of the ceiling.
A pair of spiraling pylons flank the platform, the elevated choral risers behind the platform, and the huge Casavant pipe organ. These convex pylons provide supportive reflections to the congregation, interrupt reflections from the distant concave walls, and provide a more intimate visual scale for the platform.
Faced with a directive to avoid any visible loudspeakers, Kirkegaard designed a distributed underpew loudspeaker system, supplemented by concealed line arrays in the platform steps for precedence and loudspeakers in the pylons to serve the choir. The current audio system uses exposed steerable column loudspeakers, technology developed since 1993.
The room is dramatic and unique, an inspiring place for worship and contemplation alike. Organ, choir, orchestra, and congregational singing are all beautifully supported by the clean, reverberant acoustics.