We have listed each fabric with it's NRC (noise reduction co-efficient) rating to tell you how efficiently the fabric absorbs sound wavelengths.
Every fabric will absorb different wavelengths differently, the hardest to absorb being the base sounds....duff duff etc.
A perfectly sound absorbtive material achieves a 1 NRC, wheras a 0 indicates no absorbtion.
Curtains at 2.5 times fullness should cut the reverberation by half and won't make the room completely dead.
It is also recommended that accoustic drapery sits 100-120mm out from the window, and this can be achieved by using the right brackets.
If you are having difficulty believing that a sheer can make a difference to the reverberation in a room have a look at the video from our supplier Materialised, click here.