Acoustic consultant John McDonald, who drew up the design brief, explained that "the objective was to make the sound as natural as possible. The chapel as a very pleasing acoustic, so we wanted to use natural reverb to enhance the sound. The main problem was the separation of noise source from the choir and organ, so that people sitting below the gallery could hear what was happening above." For this purpose, microphones have been centred in the choir area which are automatically activated when the choir begins to sing, and this sound is relayed to the speakers under the balcony.
Steele's commissioned TOA Corporation to build a complete 24-unit rack, comprising 8-channel automatic mixer, mic pre-amp, graphic EQ, digital delay and two power amps. This is sited in the organ loft; because it is all automatic, there is no need for any manual control. "The Chapel has an unusual shape," continues John McDonald. "There are a lot of seats for the professors and other university people in what would normally be side stalls. This required wide coverage and high intelligibility from the speakers." As a result, six constant directivity speakers have been installed in the main sanctuary, the organ loft and the underbalcony.
(Ruth Rossington)
