The basic materials of the room walls and of the 3D objects walls are selected from the Materials Data Base. The sound absorption coefficients of the materials influence the reverberation time and thereby the evaluations of the Acoustic Ambiance.

Additionally you may define special rectangular areas (Material Surfaces) within a wall. The Material Surfaces simulate e.g. doors, windows, curtains, or carpets. Their sound absorption coefficients will usually differ from that of the respective wall.

Material Surfaces are two dimensional and will therefore not influence the calculating times, whereas three dimensional '3D objects' (e.g. furniture) will increase calculating times noticeably because '3D objects' introduce additional sound absorbing and reflecting surfaces into your room design.

Make use of 'Guidelines' to meet the exact dimensions of the 'Material Surfaces'.