Methods of room acoustics


In acoustic planning, absorption is especially important for the reverberation time. During absorption, sound waves are absorbed by a material, and their energy is converted by friction into heat. Sound waves that are not absorbed are reflected by the material or object. The absorption coefficient indicates how well a material absorbs sound. Moreover, a product has the ability to absorb to varying degrees in different frequencies. Thin materials typically exhibit poor to moderate absorption in low frequencies but good to excellent absorption in high frequencies.


Sound shielding is used to reduce the sound propagation in a room. Special sound shields can have a positive impact on speech intelligibility (STI). In addition, vertical shields create privacy and a feeling of intimacy. Sound shields need to be of a certain size in order to achieve a good level of effectiveness. Effectiveness is further increased if these shields are designed to be absorbent.

Reflection / Scattering

Sound waves that strike a hard and smooth surface are reflected back into the room from this surface. In acoustic planning, reflection – or scattering – can be used in a purposeful way, for example in order to direct the sound in a large room, such as a theatre, as far as the last row of seats. Structured surfaces reflect incident sound waves in different directions. Thus, the sound is distributed uniformly in the room and a diffuse sound field results, without disruptive acoustic artefacts such as flutter echoes or standing waves, which is generally perceived as pleasant. In order to use the positive effect of scattering, elements that either have a structured surface or are arranged in such a way as to create a three-dimensional structure are utilised.

Examples of XAL products


acoustic suspended


acoustic suspended


acoustic suspended


acoustic round
MOVE IT 25 / 45 ACOUSTIC 1200 square inlay


acoustic inlay


ceiling / suspended