Knauf AMF Ceilings secret speaker makes a big noise in lecture hall

Bournemouth University has recently completed work on a £3.8m rebuild of its Kimmeridge House facility. The project included a new 70-seat lecture theatre and two large seminar rooms, along with the new 308-seat Large Lecture Theatre, where Knauf AMF Ceilings were specified to help meet the complex acoustic requirements. For the majority of time the Large Lecture Theatre is used for student lectures, which require high sound absorption to reduce the reverberation time and enhance speech intelligibility. However, the theatre is also used for musical concerts and recitals that need lower sound absorption and differing levels of reverberation. To overcome this issue, a sophisticated processing system has been installed that allows the reverberation in the theatre to be adjusted to suit the specific situation, whether short reverberation times for lectures or longer reverberation times tuned for a particular concert. With such high-tech equipment, it was essential that the ceiling system would work effectively to enhance the variable acoustics. Knauf AMF Thermatex Alpha ceiling tiles were chosen for the Large Theatre as they provide Class A sound absorption. They are lightweight and have a strong, white surface that gives a smooth, elegant appearance. Alongside this, 20 Knauf AMF Soundmosaic tiles were also installed. The Knauf AMF Soundmosaic is a flat-panel loudspeaker in a modular ceiling format that works on the principle of wave conversion. This means the mineral fibre ceiling tile itself is the loudspeaker, the oscillation being produced by a module on the reverse of the tile. This means the ceiling tile looks identical to the rest of the Knauf AMF ceiling, and Soundmosaic is available in all Thermatex face patterns. The wave converter as the source of oscillation constitutes a significant part of the loud speaker system. To optimise the effect of the sound, the adjoining tiles are integrated and linked to each other by hold-down clips. The low weight of the product allows for the system to be installed in both new-build and retro-fit or refurbishments without the need to alter the ceiling grid. Steve Gosling of 24 Acoustics, who designed the system, was impressed with the Knauf AMF products, as he notes: “The Soundmosaic tiles provide a very wide spatial response which helps mask the location of the sound source.” The large lecture theatre at Bournemouth University can now offer tailored acoustics depending on use, which is something that has previously only been available to much larger scale facilities.