Long reverberation times can be reduced by using materials which are good at absorbing sound. This property can be described by means of a sound absorption value.

Hard and rigid materials with a smooth surface often have a low sound absorption value, while materials with a soft, uneven or porous surface typically have a high sound absorption value.

Sound absorption with hard and smooth surfaces		Sound absorption with uneven or porous surfaces

The higher the proportion of the room’s total surface area that absorbs the sound, the less reverberation there will be in the room. Therefore, it is important to select a material with a high sound absorption value for large surfaces.

In this way, it is possible to regulate and reduce the reverberation time to achieve a good acoustic environment with a clear acoustic image.

The ceiling will usually be the easiest surface to acoustically regulate, since it is both large and accessible.

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