Video Screens for Hearing Research: Transmittance and Reflectance of Professional and Other Fabrics

Virtual reality labs for hearing research are commonly designed to achieve maximal acoustical accuracy of virtual environments. For a high immersion, 3D video systems are applied, that ideally do not influence the acoustical conditions. In labs with projection systems, the video screens have a potentially strong influence depending on their size, their acoustical transmittance and their acoustical reflectance. In this study, the acoustical transmittance and reflectance of six professional acoustic screen fabrics and 13 general purpose fabrics were measured considering two tension conditions. Additionally, the influence of a black backing was tested, which is needed to reduce the optical transparency of fabrics. The measured transmission losses range from -5 dB to -0.1 dB and the reflected sound pressure levels from -32 dB to -4 dB. The best acoustical properties were measured for a chiffon fabric.