Convention Paper
A Preliminary Evaluation of 360 Degree Concert Halls
AES Convention 61 · Paper 1420 · November 1978
Abstract
The problems which have beset recently-opened 360 degree concert halls are described and qualitative explanations offered. Confusion factors in auditorium acoustics include the conflict of visual beauty with good acoustics and the assumption that an acoustician can make any shape hall sound good. The inadequacy of reverberation time as an estimator of quality is discussed. Experience from three 360 degree halls indicates a general weakness of the bass clef instruments. The absence of reflectors on the sides, top and behind an orchestra makes it musically difficult to give an inspired performance. Auditory backwards inhibition explains why the musicians complain of not hearing each other. Compared to traditional halls, the audience hears a different sound quality which is explained by musical instrument directional patterns and the timing of reverberant sound in the hall. In at least one 360 degree hall, auditory backward inhibition makes it impossible to understand the human voice. In this same hall, audiences severely criticized the acoustics after a jazz concert. Recordings made in another 360 degree hall are inferior to those made in good traditional halls. The author's conclusions include seven reasons for not building more 360 degree concert halls.
