Variable room acoustics has been a topic of big interest throughout the last years. This session starts with some general background information on acoustics for theatre and vent, before focusing on practical issues for materials and solutions on site. By the use of fabrics installed as curtains or roll banners it is possible to dramatically change the acoustics of a venue due to different events taking place in one and the same room. Choosing the suiting material and using it in the right amount and correct installation can improve the acoustics event more. In addition, bass absorbing materials can be added to control the overall sound.