changeNOW, Europe’s most impactful sustainability summit, presents an audio engineer’s ultimate challenge: twenty simultaneous performance zones operating across Paris’s iconic—and iconically reverberant—Grand Palais. The three-day event hosts 40,000 attendees from 140 countries in a unique format that combines international conferences with live artistic performances. Six main stages plus fourteen additional performance areas must function simultaneously throughout the event, creating massive sound spill challenges in the glass-domed venue. Previous editions relied on headphone systems to solve the interference problem, but this isolated audience members in individual audio bubbles. This year, changeNOW and events agency Moma Event – led by Production Director Catherine Durand and Technical Director Olivier Duraton – challenged Fleik, their audio partner to eliminate those headphones entirely while maintaining pristine sound quality across all twenty zones—proving that traditional sound reinforcement could conquer even the most demanding acoustic environment.

(Above): changeNOW sustainability summit chooses L-Acoustics L Series to conquer its demanding acoustic venue, Grand Palais

The technical hurdles were significant. “The two main challenges were limiting interference between the six main stages and enabling the balconies to use traditional loudspeaker systems rather than silent headphones,” explains Antoine Secondino, Co-Founder of Fleik.

Rather than implement a complete system replacement, Fleik took a methodical approach to validation, testing their concept incrementally. “We tested the concept on the first day, running loudspeaker and headphone systems simultaneously,” Secondino notes. “Gradually, as adjustments were validated on site, we removed the headphones in favour of conventional broadcasting.”

Precision Through Prediction

Fleik’s solution centred on an L-Acoustics L2 system for the main Legacy Stage, where speakers would be using omnidirectional microphones. L Series was chosen for its ability to deliver clear sound for both spoken word and music, while limiting spill into adjacent zones and backstage areas. The team collaborated with changeNOW over eight months of planning and design, developing and refining dozens of plans using L-Acoustics Soundvision 3D audio modelling software to achieve the desired result.

Achieving the desired performance at this scale demanded precise predictive modeling. Soundvision’s integration with 3D design tools like Vectorworks and SketchUp enabled the team to optimize each system within the venue’s complex architecture before any equipment arrived on-site.

“Soundvision proved essential,” notes Jérémie Kokot, Co-Founder at Fleik. “It helped us predict coverage patterns, SPL distribution, and interference zones, allowing us to size our systems to the nearest enclosure with surgical precision—which was absolutely vital for this project.”

Strategic System Configurations

Legacy Stage, with an LCR setup served as the acoustic anchor: dual L/R hangs L2/L2D, a center cluster of four Kiva II, and ground stacked KS21 in cardioid. Syva/Syva Low pairs provided in-fill, with X8 enclosures handling front-fill, while Kiva II arrays covered the surrounding stairways

Collective Stage deployed nine Kiva II per side, center cluster reinforcement, and dual cardioid SB18 stacks maintaining essential acoustic isolation between zones.

Gallery Stage featured Syva/Syva Low pairs augmented by SB15m and Syva Sub configurations. A unique delay solution saw discrete Soka enclosures mounted on lighting totems around the audience area.

Agora Stage utilised dual seven-element Kiva II hangs with out-fill arrays and SB18 low-end support.

Garden Stage mirrored the Syva-based approach with SB15 reinforcement and four strategically positioned Soka for delay coverage.

Multiple intimate performance areas (70-220 capacity) across balcony zones, workshops, and community spaces employed precisely placed X8 systems with dedicated 108P monitoring.
LA12X and LA4X amplified controllers with P1 processors powered all areas, and all equipment was provided by L-Acoustics Certified Partner, Novelty.

Each stage system was carefully tuned to minimise audio interference while maintaining full-range coverage for diverse programming spanning voice as well as recorded and live musical performances. Fleik prioritised line-source systems over point source throughout the installation for their ability to accurately direct sound to minimize interference between stages.

Breakthrough Results

“The beauty of this project lies in what it represents,” says Secondino. “We didn’t just solve an acoustic puzzle – we proved that we don’t have to compromise between event complexity and audio quality. Traditional sound reinforcement can work everywhere, even in the most demanding environments, when you have the right tools and the courage to push boundaries. The feedback was unanimous: both the end clients and our production manager were blown away by the result.”

For more information on changeNOW please visit www.changenow.world. More information on Fleik can be found atwww.fleik.fr

More information about L-Acoustics can be found at l-acoustics.com