Our absorbers are particularly used for the damping of low frequencies below 100Hz. While the peak points into the room, the columns are to be placed, according to the room`s seize, in the corners or at the side walls. By this, bass-booming or bass-banging can be effectively damped. For a 20m² sized room, 3-6 colums are needed in average. If required, foams can be coated or covered with film scrims by you, without an appreciable reduction of the absorption effect. The plates should not be painted or varnished from you, as the pores would clog and harden, thus the absorption effect would get lost.