Flutter echo

In rooms, a “flutter echo” can occur when sound energy oscillates between parallel surfaces for a longer period of time. It occurs when a sound signal moves several times between at least two highly reflective surfaces. A floating echo can be perceived subjectively. It is generally perceived as disturbing and should be avoided. These false echoes, which can also occur between front and rear walls or between side walls, must be avoided by various measures.

In many rooms, it is possible that reflections from the rear wall, but also with the participation of the side walls, reach the front area of the room with a considerable delay in relation to the direct sound. This can be avoided by bending the rear wall or by tilting its upper part towards the room.

If it makes sense in terms of optimising the reverberation time, parts of the rear wall can also be designed to absorb sound. The side walls should also contribute to the sound supply to the rear areas of the room by a noticeable deflection of reflections. A reduction of this effect can be achieved by a geometrical design of the part and/or by partially covering the reflective surfaces with an absorbent material. Our team of experts will be pleased to advise you on this subject!