Know-how

On the Road with CANTUS and NEXUS

Peter Flückiger, what exactly sets your O.B. Truck concept apart from other approaches?

Our O.B. Trucks are special in that we work not only with two fixed NEXUS base devices in each Truck but also with a pool of portable base units that act as stage boxes. Only one thin, lightweight optical cable is required to connect these stage boxes to the O.B. Truck. Multicore cables that are prone to interference and expensive are a thing of the past.

Does the pool concept mean that you move the portable units around?

Exactly. This pooling system allows us – a small broadcasting corporation with limited budget – to use the available equipment with uttermost efficiency. There are eight portable NEXUS units in all for two large and three medium-sized O.B. Trucks. The units – each of them provides 20 microphone and 8 line inputs – are used wherever they are needed. This flexibility saves us a considerable amount of money. Up to four of these stage boxes can be connected to one O.B. Truck.

Are there no technical limitations?

You are right. In a conventional NEXUS network, a given base device might not be freely connected to any other unit because of its »name«, i.e. its unique Base Device ID. This address identifies a unit within the network. Therefore, we requested more flexibility for our O.B. Trucks. The solution turned out to be simple but highly efficient: every stage box is equipped with a switch providing free manual selection of any Base Device ID between 0 and 15. This is all you need for configuring your NEXUS system as you go. Now any stage box can be connected to any O.B. Truck.

But that's not all: the two large O.B. Trucks are identical as are the three medium sized ones, thus allowing us to switch from one Truck to another as and when necessary. This also applies to the CANTUS and NEXUS configurations: we can freely exchange configuration and automation settings between Trucks, knowing that the quality standard will remain the same.

Why do you need so much flexibility?

Oh, there are various reasons for that. First, scheduling of O.B. Trucks and crews is much simpler when all Trucks have almost the same features and methods of operating. Furthermore, we make a surprising number of outdoor productions in Switzerland – just think of skiing or cycling events and the number of microphones required for covering such events. Then there are also spectacular events such as the ascent of the north face of the Eiger. With optical cables and multiple NEXUS devices along the road, long cable runs are no longer a problem.

Finally, there is also the consideration that our big O.B. Trucks cannot go to every location, what with the narrow roads in some areas. That is why we have to be flexible with respect to the number of base devices and the configuration of our NEXUS networks. As far as I know, we are the only ones who can establish a star network between our O.B. Trucks and two NEXUS base devices and then connect two additional NEXUS base devices in series!

Does this mean that you mainly rely on optical connections outside the O.B. Trucks?

It does indeed, because that gives us the best quality possible. I believe that when it comes to optical cables for on-location jobs, we are probably the most advanced crew in Europe. The only reason why we still have 12 microphone inputs for conventional multicore cables is that extreme weather conditions may not allow us to use the optical option. However, make no mistake: our NEXUS stage boxes also work when it is snowing or pouring down. Optical cables are undemanding in this respect, which is why we think of controlling the talkback system via NEXUS devices and distributing the signals via the optical network.

Our only technical problem to date has been of a totally unexpected nature: one fine day, a cow found one of our optical cables delicious, so the connection broke down!