References

Olympic Games in Athens  

“The heart of the world beats in Athens!” These were the words the president of the Republic of Greece Constantinos Stephanopoulos said to 72,000 visitors of the opening ceremony of the Olympic Games in the Athens Olympic Stadium on 13 August. More than 200 loudspeakers and over 90 power amplifiers made him audible even in the most remote corners of this new giant stadium. This is a unique success for SALZBRENNER STAGETEC MEDIAGROUP, too, as they had implemented the entire digital audio network for the loudspeakers and the control and monitoring components in the Olympic Stadium.

The system provided by SALZBRENNER STAGETEC MEDIAGROUP comprises a NEXUS routing system combined with a C.A.S. control and management system. All announcements, playbacks, and other audio signals from the stadium control room are distributed via optical fibres to three NEXUS units in three technical centers in the stadium from where they are forwarded to the speaker system amplifiers. The installation of the NEXUS units in the technical centers was itself a considerable challenge because two subcenters are located more than 40 meters above the ground in so-called tubes sited just below the stadium roof. The main center is situated next to the control room on the stands level. It houses a NEXUS unit featuring I/O boards to provide connectivity to the C.A.S. system and also control interfaces for monitoring the whole speaker system. The unit even is equipped with two DSP boards for processing signals for the entire sound-reinforcement system. All three NEXUS units are networked with a star topology. All audio, control and monitoring data are communicated between them via fibre-optic cables with a total length of more than two kilometers.

A number of specific requirements had to be considered already during the planning stage of the large sound-reinforcement system to meet the high safety standards of the Olympic Stadium. Preventing a failure of the sound reinforcement system was a key objective. For this purpose, SALZBRENNER STAGETEC MEDIAGROUP designed new hardware controllers allowing for switching from the high-power amplifiers (up to 2,000 W) to backup amplifiers if required.
In addition, the Olympic Stadium is subdivided into 24 zones with separately addressed and monitored speaker groups. This is important in cases of emergency when announcements dedicated to individual stadium zones might be necessary. Presets for the C.A.S. system were defined, allowing for quickly addressing individual zones or groups of zones. The C.A.S. also provides for continuous monitoring of all speaker lines.

The planning stage of this project started about 18 months before the opening of the games. Even so, the SALZBRENNER STAGETEC MEDIAGROUP were considerably pressed for time because of the sluggish construction progress in Greece. Therefore, a large part of the audio network was preconfigured at the company headquarters at Buttenheim. The system in Athens now has a fallback line to computers at Buttenheim, allowing for remote software support and maintenance from Germany with no need for an engineer to be physically present in the Greek capital. Fortunately, this “remote control” has not been required yet as the system works flawlessly – this is visible (or rather audible) to all current Olympics enthusiasts.