SALZBRENNER STAGETEC MEDIAGROUP Networks
Athens Olympic Stadium
Athens, in August 2004: “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. |