초록 close

It was widely acknowledged that the proportion of a room affects the acoustic properties in that room. Especially three dimensional proportions are very important for the use and acoustical goals of halls for both music and speech. The present study aims to verify the effects of three dimensional proportion of rectangular rooms on the acoustic parameters of halls. Computer modelling and scale models experiments were undertaken using four rectangular imaged and scale models with different 3-dimensional proportions in order to measure RT, EDT, SPL, C, IACC at four receiver positions of each model. with a reference model of cubic room, length, width and height were changed to vary the proportion of the rooms. As the results, it was found that RT was affected by mainly room volume as expected regardless of the proportion of rooms while sound levels are most large in the smallest rooms where mean sound path is much shorter than others. Clarity index(C) was increased with a reverse function of RT. Especially, it was confirmed that 1-IACC, only a spatial parameter investigated, was most low in wide room. Also, it was found that higher RT, EDT, SPL were measured in the area near lateral wall rather than the central area of halls. Especially higher 1-IACC was measured in the area near lateral walls. This show that the central area of halls have a acoustic shadow zone in the wide halls. The overall estimation of the acoustic quality was also undertaken using statistical calculation using Z-score. The result represents that the long hall has a better value of acoustic properties rather than the wide or high halls.