The linear array or the curved one is useful to the sound source of sound reinforcement system, and these arrays are utilized in many applications. In order to obtain desirable directive pattern of the array, the curved array is superior to linear one. However, it is quite difficult to determine the optimum arrangement of the curved array theoretically. In this paper, a method to design the curved array is proposed. It is shown theoretically and experimentally that adequate sound pressure distribution can be obtained by the curved array designed by the proposed method. The shape of the curved array is determined by the following method. That is, the region of audiences' seats in the sectional plan of the room is divided into equal M parts as shown in Fig. 1-(b) and equidistance points from the rear wall are denoted by P_1, P_2. . . , and P_<M+1>. By the use of the angles (θ_n, n=1, 2, . . . , M) between the straight line S_0P_n(n=1, 2, . . . , M) and the horizontal line, the arrangement of loudspeakers is determined as shown in Fig. 1-(a). The results of numerical computation on the near field sound pressure distribution of the curved array synthesized by the above-mentioned method are shown in Figs. 4, 5, 6 and 8. In comparison between the near field sound pressure distribution of the curved array (Figs. 4, 5, 6 and 8) and that of the linear array (Fig. 9) it is clear in Figs. 4, 5, 6, 8 and 9 that the sound pressure distribution of the curved array within the objective region is flatter than that of the linear one. Furthermore, the changes of the sound pressure distribution with respect to frequency in the case of the curved array are less than those of the linear array. Experiments on the sound pressure distributions of the curved array were carried out in order to verify the theoretical considerations. It is observed in the experiments that there exists some difference between the results of the curved array and the linear one, as shown in Figs. 11, 12 and 13.
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