The main point for the choice of the Bosch system, says the company, was the fact that Praesideo easily met the tough EVAC requirements for Terminal 1 and is "far more cost-effective than would be possible with an analogue system". Additionally, the system has been independently certified to the IEC 60849 safety standard.
Terminal 1, which handles the bulk of the international traffic of Paris' largest airport, presents special challenges for a PA installation. Managing the flights of around 60 airlines, the circular terminal covers seven floors and includes a central building and seven departure satellites to which passengers are conveyed through transparent tubes. In a terminal of this size, the installation of a traditional analogue PA system would require an enormous amount of recabling. Unlike traditional PA systems, the Praesideo uses a network configuration based on fibre optics.
Axians started the installation in 2004, after performing an acoustic study to check how many loudspeakers would be needed in each part of the terminal. The main control room was first installed in the central building, followed by smaller control rooms in each of the departure satellites. These were connected to the main control room by fibre-optic cabling resulting in a total of 13 interconnected Praesideo PA systems and 12 emergency zones.
One of the challenges facing the installers was maintaining the old analogue PA system in operation during installation of the new digital system. Once the new hardware was in place, Bosch were able to hook up to the old cabling and speakers while they installed the fibre optic network, making the switchover from the old to the new PA system smooth and seamless.
The system is currently operating with the original speakers which Axians is due to replace in phases, starting this year and ending in 2007. When complete, the system will boast 1000 Bosch MCS 3500 ceiling mounted tri-cone loudspeakers and 50 XLA 3200 line-array column loudspeakers.
(Jim Evans)
