Acoustical considerations for improving spatial impression in designing concert halls

Abstract

One of the major acoustical considerations in designing concert hallsisimproving spatial impressions through providing more early lateral reflections.The lateral energy fraction (LF) and the interaural cross correlation (IACC) are useful measures for assessing design alternatives in a viewpoint of better spatial impression. In this paper, design developing process for improving spatial impression was demonstrated with a concert hall case.In the early design stage, a bell-shaped cross-section with vineyard seating was proposed to enhance the lateral reflections for the audience. The main reflecting surfaces, which were stage enclosure, lateral walls, balcony fronts, and ceiling, were evaluated to optimize the shape and angle for early reflections. The horizontal diffusers were additionally installed for the improving the spatial impression. The validation was performed with computer simulations and 1:10 scale model measurements for the evaluation of the alternatives.