Background
Anderson Acoustics was commissioned by Gurdwara Sri Guru Singh Sabha, a Sikh temple in Southall, London, to advise on potential design changes to improve the acoustic conditions for event use of a 2,300 m3 hall space.
What we did
We undertook an acoustic survey of the hall and a 3D acoustic modelling exercise to demonstrate potential acoustic treatments to mitigate against the current challenges experienced in the space.
- Acoustic Survey
Reverberation tests were carried out in the unoccupied space using a starting pistol located in corners and edge positions in the hall to generate a diffuse impulse noise signal throughout the space. The measurements confirmed the existing reverberation time in the space to be excessive causing speech sounds to be blurred so resulting in poor speech intelligibility.
Observations made on site also indicated the presence of ‘flutter echoes’ caused by the two side areas of the space. This characteristic occurs in a space where two parallel surfaces are reflecting sound between one another and causes an audible ‘echo’. Gurdwara staff commented that this condition was having a negative effect on the space, causing the two side areas to be avoided by worshippers.
Reverberation time criteria for this multipurpose hall are based on the acoustic performance standards in Building Bulletin 93 Acoustic Design of Schools Performance Standards (BB93), and other guidance. The performance standards in BB93 are only mandatory for schools to comply with the Building Regulations but may also be used as a guide to inform the acoustic design of other large multipurpose halls.
- 3D Acoustic Modelling
3D acoustic modelling was undertaken to determine the approximate quantity and location of sound absorbent treatment required to achieve the desired acoustic criteria.
The results of the 3D acoustic modelling exercise showed that provision of fixed sound absorbent finishes would significantly improve the reverberation time to support greater speech intelligibility within the hall.
