For his television sound mix, Fracchia needed analogue converters in the form of two Optocore X6R-FX-8MI/8LO because only four MADI ports were available on Silence’s Vista 5, and these were required for stageboxes and multitrack recorders. (This is part two of a two-part feature. Click here to read part one!)
Analogue audience mics were also captured and distributed via the Optocore preamps.
The Vista 5, meanwhile, streamed orchestra, choirs and final mix to FOH, where all mixing consoles were connected to the Optocore network via MADI. This protocol was recovered via three Optocore DD2FR-FX: two for the Lawo NOVA routing system, which was connected to both LAWO MCe32 and MCe 24 consoles, and one for the Yamaha DM1000, which was equipped with a 16 I/O MADI card.
While the DM1000 handled advertising play-ins and firework soundtracks, both Lawo desks were used to capture live the Grand Orchestra and Great Choir of Radio France (and soloists).
In total six DD32R-FX interfaces were deployed, along with two older X6P-8MI/8LO – connected to AES ports of the DD32R-FX – three DD2FR-FX and six X6R-FX-8MI/8LO.
Both the Lake LM44 processors and Lab.gruppen PLM20000Q amps were connected to the Optocore network via AES3 from a DD32R-FX with analogue back-up.
Finally, production also used analogue video monitoring devices, utilising composite video I/O built into the DD32R-FX and DD2FR-FX, for control in the OB van, FOH and the fireworks soundtrack.
Bruno Lompech states: “The Optocore solution not only brought us the peace of mind necessary for an event of this magnitude, but the technology itself, the simple implementation and security against external interference through the use of the fibre were all huge advantages.
“I was also impressed by the minimal latency time for the routing of signals – whether they be analogue, digital or in the MADI format – and this proved that we were working with a team skilled in providing signal transport infrastructure out in the field and that Gilles Bouvard was the right provider.”
Lompech’s original request had been merely to set up a number of secure signal transport topologies from the console to the various control locations. “But we realised we could use the Optocore network to route signals from the ambient mics to the mobile recording unit and also to connect the outputs of the console returns to the stage monitor amps,” he observes. “Finally, we were able to use the Optocore network for routing and analogue video signal control.”
He adds that for the future he is already considering a more comprehensive solution where the whole transport of microphone recording can be entrusted to the network. “With the MADI protocol being present on most consoles, signal transport time being so fast and Optocore’s high-quality preamps corresponding to our expectations, a sharing of resources will produce an even more qualitative solution. In terms of installation this will greatly simplify the task.”
For Gilles Bouvard (pictured, left, with Bruno Lompech) one of the most exacting challenges in managing a digital network between several mixers was to master digital synchronisation “between Optocore and the rest of the world”. He explains: “In order not to lose sync, given the difficult configuration of the network, we relied on the Optocore master clock, expertly managed by François Iund.”
Other factors in the successful Optocore deployment included the 41µs latency, crucial in classical music, the high-quality rangbrobese of Optocore converters and the speed and simplicity of implementation, he says. “This was a recognition not only of the capabilities of the system but our own expertise.”
Such is the strength of their resource that GB4D were simultaneously handling a similar Bastille Day festival in the city of Toulouse, where they used 22 Optocore devices to cover distances of up to 6km (3.7mi). “The reason we are able to undertake such large projects requiring Optocore, is because we have 18km of quad single-mode optical fibre in our rental fleet,” he concludes.