Acoustical design of the Kyoto Concert Hall

Abstract

The Kyoto Concert Hall was planned as the 1200 years’ memorial facility of the ancient metropolis, and was opened in 1995. It consists of two concert spaces: the Main Hall with 1833 seats as the home of the Kyoto Symphony Orchestra (KSO), and the Ensemble Hall of 500 seats. The shape of the Main Hall has essentially come under the category of ‘‘shoe box,’’ with two steps of balconies surrounding both the main audience floor and the stage. The basic room dimensions were fixed following a computer simulation study regarding the distribution of early reflections. Sound scattering elements were introduced on the lower side walls and the ceiling. The diffusing effect, namely, that the elements make the sound field uniform, was confirmed by a 1/10 scale model study. Other design elements are: a heavy concrete ceiling, a timber floor over an airspace, absorptive audience seats, an orchestra riser system, and the selection of a stage timber floor by audition. The Ensemble Hall has a hexagonal plane. In order to compensate for an insufficient ceiling height of 9 m, the walls were tilted 12 deg outward to delay the arrival time of some early reflections, and absorptive curtains were installed temporally to be available for adjusting to a variety of music.