DYNAMIC VARIATIONS OF DIRECT AND REFLECTED SOUND PRESSURE LEVELS USING BEAMFORMING

Ancient theaters are used for live performances for a variety of venues, and there is a demand for detail information relating to sound field within these remarkable historical architectural buildings. The objectives methods used to examine these types of spaces for their room acoustic characteristics are on site measurement at their current status and structural integrity, computer simulation and or scale models incorporating the past archeological records for their architectural details that relate to material and surface characteristics. The objective of this study is to demonstrate the ability to visualize sound fields of real and simulated spaces. Research objectives are to capture a space sound signature that significantly represents the characteristics of all architectural elements with their contributions to the room acoustics toward their historical preservation, and to visualize the audible impact of these elements, and represent these acoustic conditions within a virtual environment for the general public to experience. This paper describes a new approach in measuring the contribution of various frequency ranges for evaluation of the existing condition of the Rome Coliseum. Data were measured using Acoustic Camera spherical array, 120 channel data recorders, and utilizing various acoustic software for data reduction, computer modelling, simulation and analysis. The measured and simulated results based on these parametric studies are compared against selected well-known studies of Greek and Roman theatres. As part of the new historical preservation effort, and given the historical records on the use of materials with their unique surface characteristic, the frequency domain and spectral analysis are used as input to the computer modelling, simulation and analysis of the space. Newly developed room acoustic indicators provide a new approach in estimating the impact of the direct and reflected sound contribution to the sound level available within the current space. The results show a new research approach in room acoustics evaluation utilizing current standards and techniques