First, the design and layout of the loudspeaker system to beam the sound in the required directions – different loudspeakers were needed for different areas; some highly directional with electronically controlled beam-forming and others more conventional. Secondly, the acoustic design of the surface finishes to control the reverberation of sound in ‘cathedral’ size volumes.
All other acoustic design work flowed from the main theme, in particular, the control of background noise from various sources to levels which would not interfere with speech intelligibility. Aircraft noise was controlled by the design of the building envelope and mechanical services noise was reduced by the selection of quiet plant and suitably sized silencers.
The result of our design approach is that, in addition to voice announcements being highly intelligible, passengers and workers alike enjoy a pleasant and calm aural environment.