The Opera House has around 1000 rooms with a total surface area of 41,000sqm, divided into some 280 extensive acoustic zones with 1,200 loudspeakers in all. The feed to the speakers comes from 79 Praesideo power amplifiers, which are in turn controlled by two network controllers. These form the heart of a Praesideo system: among other things, they monitor the operational readiness of the entire system, route live announcements precisely to the appropriate areas, play back digitally stored messages and play background music over the 28 available audio channels. There are four Praesideo call stations and two fireman's microphones in the Opera House for live announcements. The fireman's microphones are located on the right and left of the main stage.
The Praesideo system is housed in four groups of 19" control racks, which are located in strategic positions throughout the building. Three of these are connected by fibre optic cables and form a form a Praesideo sub-system. The fourth rack forms a second independent sub-system, which is interconnected by copper cables to the first subsystem.
The speakers had to fulfil contrasting demands: they had to be as unobtrusive as possible, without sacrificing reproduction quality. This was solved by using primarily LBC3500 type speakers set into the ceiling. These speakers have an especially wide angle of dispersion and offer high-quality reproduction of both voice and music. Bosch type LBC3201 line arrays were installed for emergency announcements in the 1700-seater auditorium. Thanks to the considerable range, only six of the arrays were needed on either side of the main stage.
The installed system is a combination of Praesideo with a Dateq MusiCall system. Each of the 280 acoustic zones has a small MusiCall wall-mounted digital control panel for operating Dateq's MusiCall Digital Matrix Mixer. Staff can use the wall panels to switch each zone to one of up to four sound channels: announcements, main stage, rehearsal stage and background music. The MusiCall Matrix and the Praesideo power amplifiers were matched to each other and housed in the control racks.
(Sarah Rushton-Read)
