October 2004 - The head office of the T-Mobile telecommunications group is a massive 123,000 m2 complex in Bonn, accommodating
around 5,000 employees. Its impressive entrance hall, itself covering an area of 2,300 m2, houses Europe's largest indoor LED
wall, and a powerful surround sound system powered entirely by CAMCO amplifiers.
Installing a good sound reinforcement system in the hall represented a challenge for consultants, the Walters-Storyk Design Group
Europe. The rectangular room has glass walls on the left and right and the mobile dividing wall at the rear is also hard and
acoustically reflective. Despite this, T-Mobile wanted a surround system based on the established criteria for cinema sound
The client didn't want to see additional acoustic elements in the hall so the only workable solution was to use a system in which
coverage could be directed as precisely as possible. The obvious choice then was a line array system, a compact solution from
the French manufacturers NEXO, driven by CAMCO's Vortex amplification.
On both sides of the LED wall, two banana-shaped arrays of NEXO GEO cabinets, divided into two segments for control purposes. As
the centre loudspeaker could not be positioned behind the acoustically reflective LED wall, a smaller array was mounted in the
limited space above the display, supplemented by front fills below the LED panels. The front fills are for first few rows to
ensure the sound is perceived as coming from the stage.
The line arrays are driven by CAMCO Vortex 6 and Vortex 4 amplifiers mounted in a rack behind the LED wall. The amps are
connected to a digital controller (NEXO NX241) which in turn takes its signal from an AudiaEXPO-Expander biamp. Via CobraNet, the
Audia Converter is connected up to the forum control room, where the central units are accommodated. The signals are received
and processed by two biamp AudiaFLEX processors, which then distribute them to the appropriate amplifier or loudspeaker