Notre-Dame is getting a high-tech upgrade – and this time, it’s all about sound.
After a devastating fire in 2019, Sennheiser has installed a next-generation wireless audio system as part of the cathedral's' restoration, providing wireless coverage for microphones and transmitters.
The challenge wasn’t just reaching every corner of the building – it was doing so in a way that remains unobtrusive in one of the world’s most iconic and historically sensitive landmarks.
Novelty, the integrator responsible for re-equipping Notre-Dame, selected Sennheiser for the task.
David Créteur, Project Lead at Novelty felt the old system – an analogue two-channel Sennheiser 3000 series – was due an update.
“Instead of working only along the axis, we now had to cover almost the entire cathedral, which is just over a hundred metres long from the entrance to the back and almost 50 metres wide at the transept.
"With the digital wireless technologies we were familiar with, we could have done it, but we would have had to multiply the number of antennas to a total of at least eight to be placed throughout the building, and then connect them with long lengths of cable.
At more than 100 metres long and nearly 50 metres wide at the transept, Notre-Dame is a highly challenging environment for wireless signals. It has thick stone pillars, wooden partitions and constantly changing audience layouts.
Just as importantly, the system had to be discreet and simple to operate. Services take place alongside visitor tours.
Clergy, technicians and broadcasters all share the same space. Any solution would need to work reliably in the background, without constant manual intervention.
Moving Beyond Traditional Wireless
Notre-Dame’s previous wireless system relied on an analogue two-channel receiver and centrally positioned directional antennas.
While adequate for more limited use cases, it was no longer sufficient for the expanded coverage required following the restoration.
Achieving full wireless coverage using traditional approaches would have required at least eight antennas distributed throughout the building.
They would have been connected via long coaxial cable runs – which would introduce signal losses, increase complexity, and in a historic environment, pose significant installation and aesthetic challenges.
Fibre-based extension systems could have mitigated some of those issues. However, they would add expense, complexity and operational overhead, particularly when it came to antenna zoning and manual activation.
Instead, Novelty turned to Sennheiser’s Spectera system, the company’s implementation of WMAS (Wireless Multichannel Audio Systems).
The team could reduce the number of antennas from eight to four while still achieving consistent wireless audio coverage throughout the cathedral. Automatic antenna combining removes the need for manual zoning.
