The effect of dome cover on acoustic performance in multi-purpose halls and case study

Acoustic design becomes difficult in multipurpose halls as speech and music functions require different optimum condition. Additionally, the forms, dimensions etc. of the surfaces in the volume are acoustically important. Because the surfaces should direct the sound to the audience area in a planned and effective manner and shouldn't cause acoustic defects. Studies on acoustic evaluation of concave surfaces; shows that the dome cover causes defects such as focusing the sound in certain parts of the volume and not spreading it evenly. The aim of this study is to develop suggestions for improvement of acoustic performance and elimination of acoustic defects in a multipurpose hall with a dome cover and to question the effectiveness of these suggestions for different acoustic design approaches(natural acoustics, electroacoustics, integrated acoustics) and to provide designers acoustically in terms of the use of concave surfaces halls to provide additive design inputs. Eskişehir Bilim, Sanat ve Kültür Merkezi was determined as the case study due to the discomfort experienced by the performers and the audience because of the dome cover. Within the scope of the study, acoustic measurements were made in the field for the analysis of the current acoustic situation and a calibration model was created with ODEON Auditorium(14) software. 2 scenarios developed to improve the current situation of the hall are objective acoustic data obtained from 8 different hall designs, diversified over natural acoustic, electroacoustic and intagrated acoustic design approaches were evaluated. With the evaluations made, the necessity of making acoustic improvements to provide auditory comfort in multipurpose halls with dome cover has been reiterated. Due to the fact that the determined volume is too large for the number of spectators, the half-open model from the 2 scenarios developed is supportive in terms of preventing acoustic defects, but insufficient in some aspects in terms of acoustic parameters. However, suitable results were obtained in terms of acoustic defects and parameters in the model that completely covers the hall.