The measurement of reverberation time is of importance for several purposes. Examples include:

• Calculation of airborne insulation of building elements (ISO 140’Äì3/4);
• Determination of optimal speech intelligibility in spaces;
  Calculation of the reverberation time in the common internal parts of buildings containing flats or rooms for residential purposes (Approved Document E).

Reverberation time can be defined as the time required for a steady sound pressure level in an enclosed space to decay by 60 dB, measured from the moment the sound source is switched off. One of the few concert-hall criteria which can be defined precisely and measured with reasonable accuracy is the reverberation time. It is certainly one of the most important criteria.

It is critical for architects and other specifiers of buildings to get the reverberation time of a space correct. If the reverberation time of the space is too long, the communication of speech in spaces such as board rooms can often be difficult. The reverberation time of a space is determined by its volume and the surface finishes within that space. Hard and reflective surface finishes such as glass, marble and concrete lead to long reverberation times that may create an unpleasant acoustic environment. The opposite is true in spaces that are used for orchestral events where a long reverberation time assists and enhances the music performance.

Acoustics Plus is able to measure and predict the reverberation time of a space. Measuring the reverberation time of a space requires the measurement of the decay of a signal of suitable amplitude. This can either be through a loudspeaker or an impulsive sound such as that produced by a pistol shot. The prediction of reverberation time is undertaken through a proprietary room acoustics modelling package or through detailed calculation, whichever is the more appropriate.

New requirements contained in Building Bulletin 93 ’ÄòAcoustic conditions in schools’Äô and Approved Document E of the Building Regulations require the calculation of reverberation time to ensure stringent limits are met.

If you require further information about measuring or predicting reverberation time then please click on the building acoustics section of this website. Here you will find more information about reverberation time applications. If you require a no obligation fee quotation for reverberation time measuring or prediction, please do not hesitate to contact us, either by email (info@acousticsplus.co.uk) or phone.