Know-how

For many broadcasters, the ultimate stage in moving towards a fully digital studio complex is the digitalisation of the main switching centre. However, there are as many broadcasting services as there are concepts for switching centres with NEXUS

They only share a few common attributes. All are NEXUS-based and brand new. Since the NEXUS technology is so multifarious, they can differ in almost every other respect, above all, in fundamental concept.

Small yet Centralised

First example: The Hamburg NDR controlcentre. A direct substitution of the previous analogue system was required. The new system comprises two compact NEXUS racks, housing the entire controlcentre matrix. This exceptionally high packing density was achievable by using RJ45 sockets on 8-channel converter boards. This modern connector, familiar from computer networks, was specially adapted to the good old Siemens terminal strips, so with only a few plugs to reconnect, the new NEXUS could immediately be put into operation. Another aspect peculiar to this system is NDR’s use of Matrix 5 software and the latest generation CPU. Both were originally designed for NEXUS STAR systems, although NDR’s NEXUS is built around conventional base devices. The reason for this variation is that NDR needed one of the brand-new Matrix 5 options; the crossfade board. This is used to crossfade to and from regional programme opt outs.

Big Star

The Polish Broadcasting Service in Warsaw pursued an entirely different route. Here, the NEXUS installation was extended right into the studios. 18 distributed base devices connect to a NEXUS STAR in the control centre. This network is unusually wide, interconnecting two buildings almost 20 km (12.5 miles) apart. This gulf is spanned using a single-mode fibre to connect the second building to the STAR. This system architecture looks almost like a comet — a star with a long sub-net tail. Building this system was a real technical challenge for the SALZBRENNER STAGETEC MEDIAGROUP. Acting as a general contractor, they not only installed the audio network, but all the studio equipment for the broadcasting service.

Dual Security

The French Canal+ pay-TV service, based in Paris, runs one of the largest networks. Their existing NEXUS network was complemented with two STARs, each provides 4,096 inputs and 4,096 outputs. Under normal conditions, the total traffic is distributed between the routers. However, a single STAR has enough capacity to manage the whole network if necessary. This built in redundancy was a critical feature for Canal+, because here too, the entire internal audio cabling is based on NEXUS, with base devices spread throughout the building and into the individual machine rooms.

Distributed Control

A large distributed network with no sign of a STAR. This is a reasonable idea if you need to adopt working practices born out of the analogue world. A good example is All India Radio, AIR, the Indian government radio. At their New Delhi headquarters, AIR have completed the changeover from the analogue era to an entirely new, fully digital radio complex. NEXUS is a reassuring factor here as it has proved reliable in countless other installations, even under unusual climatic conditions. Unlike European radio ser vices, this system is designed on a decentralised paradigm. The signals are not directly routed to a control centre, but to NEXUS base devices located in primary control rooms. Each sub-centre autonomously manages the output of five or six radio studios, therefore, only a bare minimum of routing is required at the control centre.

Always Included

All four of these installations, located in very different corners of the world, illustrate an important trend. The new generation of control centres adapts to the task(s), not vice-versa. Small or large, centralised or distributed, with STARs or subnets, the choice is extensive, but always includes the very highest reliability and optimum audio quality, and of course, a NEXUS.