Real-time identification of airborne sound flanking paths using a 3-dimensional acoustic camera

Abstract

Sound transmission testing, whether conducted in the laboratory or under field conditions, is critical for quantifying sound transmission performance of building constructions and elements. When samples undergoing sound transmission loss testing are constructed in the laboratory, results can suffer from airborne sound flanking paths that may not be apparent through visual inspection of the test sample. In the field, noise reduction testing between spaces can be similarly influenced by airborne sound flanking paths that are not immediately obvious. One methodology is presented utilizing a portable calibrated device that generates accurate overlays of sound pressure level over visual images (the VisiSonics 5/64 Acoustic Camera), allowing for the successful identification of unwanted flanking paths in both laboratory and field environments. Data are presented from recent laboratory testing that show the efficacy of acoustic imaging to identify sound flanking paths in real-time, enabling users to optimize sound transmission performance of an assembly.