Anechoic Chamber Renovation

It has been our pleasure to work with the University of Suffolk (UoS) on an exciting acoustic renovation project. The facilities, now 45 years old, were built by BT for research and development testing of their telephony equipment – including speech intelligibility for home phones. These once state of the art acoustic testing facilities required complete re-furnishment. The DigiTech Centre is a collaboration between UoS and BT to establish specialist labs at Adastral Park to support regional skills development. With the advancement of technology and the progressive plans from the University, modernisation was needed.

Project Overview

Refurbishment and upgrade of

  • 2 Full Anechoic Chambers
  • 1 Mini Anechoic Box
  • 1 Reverberation Room
  • Safety Check Acoustic Electrics

Anechoic Chamber Renovation

The main anechoic testing chamber was the priority for this project. Will Pryke (Digitech Centre Project Manager) at the University of Suffolk outlined some big plans for the facility – “the main usage of this fully anechoic chamber will be to further develop our creative arts and digital communications courses. We’ll teach students how to use the chambers and how they can be used for research and development. We will also look to make the facilities available externally to the business community”.

 

The team at QuietStar completely stripped out and disposed of the existing foam wedges and steel ‘weldmesh’ grid support frames, speaker support frames, cable floor support system and corner flood lighting. These were replaced with new fire rated foam wedges and support frames, an acoustically transparent catch net below the old cable floor, new speaker support mounts, new door seals, new electrics and diffused lighting.

 

Following refurbishment, the full anechoic chamber was independently tested, and it was shown to have a cut-off frequency of 80Hz and a background noise level of 7dBA – suitable for sound power level measurements, free-field sound field audiometry and hearing protector testing.

Before and After Photos Of The Small Anechoic Chamber:

Before

After

All testing for Anechoic Chambers meet ISO 3745 and ISO 26101 acceptance criteria.

 

Mini-Anechoic Table Top Box Upgrade

The old foam in the Min-Anechoic Box was so degraded that it was unable to perform acoustically. We replaced the foam with high quality, durable foam to bring it back to life.

Reverberation Room Update

Reverberation rooms can be thought of as the opposite of anechoic chambers; instead of absorbing sound, the walls, floor and ceiling reflect sound energy. With multiple testing uses, the existing, outdated room was brought in line with the other refurbished rooms.

 

The main changes were to door seals and lighting, but we also repainted the ceiling, walls and floor to cosmetically bring the facility up to date with the other refurbishments.

 

Post refurbishment independent testing of the reverberation room found that mean reverberation time (the time for a sound such as a hand-clap to die away by 60dB) was nine seconds. This long reverberation is due to the hard surfaces having very low absorption coefficients (<0.02). The equivalent sound absorption area in the empty room meets the requirements for sound absorption tests (ISO 354) and sound power testing (ISO 3741).

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