Once the 3D model was completed the acoustic characteristics of the surfaces within the model were defined, as these play a crucial role in the accuracy of the acoustic results obtained from the simulated space. Again, the sound source is represented by the red sphere, with the grid of receiver positions represented by the arrangement of blue spheres The sound source is represented by the red sphere, with the grid of receiver positions represented by the arrangement of blue spheres Figure 18: Computer model representations of St Margaret's Church: ODEON model, looking towards the west wall and the tower. Figure 17: Computer model representations of St Margaret's Church: CATT Acoustic model, looking towards the east wall. Hence an appropriate 3D acoustic model was defined for both applications to the same level of detail, as shown in Figures 17–18. However, apart from being impossible to simulate every object and structure within a space, an extremely detailed model causes a significant increase in the number of the reflections that have to be considered by the geometric acoustic algorithm used in these applications, leading to a potential loss of accuracy in the results, especially for low frequencies. There are no standards providing recommendations about the level of the geometric detail that should be considered in such an acoustic model. These were adapted further based on physical measurements taken during the acoustic surveying process, and taking account of additional objects and furniture that had not been included in the original architectural plans. PREVIOUS NEXT CONTENTS SUMMARY ISSUE HOME 3.1 Modelling and calibrationĪ computer model of St Margaret's Church was also developed, using two leading commercial applications, CATT Acoustic and ODEON, initially based on the architectural plans created during the most recent refurbishment of the space (Foteinou and Murphy 2011).
Murphy, Shelley, Foteinou, Brereton and Daffern. Case Study: St Margaret's Church, York, UK.