  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.
