As Berlin’s first techno club, Tresor is among the most renowned locations on the international dance club scene. Opened in 1991, it relocated to an abandoned heating power plant in 2007, taking with it the vibe that had built its reputation. Now, its 25th anniversary sees the introduction of the Plus4Bar, a new dancefloor with a unique concept behind its acoustics.
Former industrial buildings are friendly to the requirements of musical performance – an elongated concrete cube was to be the Plus4Bar’s site and presented a typically difficult acoustic proposition. Pronounced reflections, room modes and a propensity for feedback made it a highly questionable environment. In order to meet the high acoustic demands of both audience and its proprietors, Lambda Labs, together with Audiophil Berlin and Ron Schneider, the Tresor’s Head of Sound, devised an extraordinary and extremely effective acoustic solution.
The requirements were clear – the room had to offer consistent sound distribution, uncompromised impulse response and immense headroom, while maintaining an extremely high resolution across the entire frequency range at every listening position. The floor’s early sound installation had disappointed and had to go, since the sound quality and technological implementation of the materials used was not up to the split test and precluded any potential for significant improvement.
At first, the acoustic conditions were analysed using a complex simulation (the so-called Boundary Element Method or BEM). This time consuming yet effective procedure takes into account not only the individual speakers’ directional characteristics, but also incorporates a physically correct calculation of the absorption factors of the different surface elements of the room to provide data for the exact positioning of the absorption material.
The choice was for 18 of Lambda Labs’ new Wideband FRP absorbers. These absorbers ensures an extremely high absorption factor even in the frequency range below 30Hz. This optimised acoustic blends into the club interior.
The bass set-up particularly required an ‘outside the box’ solution, and had to go beyond the conventional LR positioning – two vertical bass arrays each comprising two Lambda Labs DH-18 providing pressure and sonic precision from 30Hz to 100Hz. Configured in Directivity Mode, they take up almost the entire height of the room. The distance between the arrays was determined to allow a constructive overlay of the individual sources, creating a cylindrical source with an even power and pressure distribution. This minimises excitement of room modes between floor and ceiling, which achieves significant improvement on the turntable’s feedback immunity. The positioning on the wall increases the radiation impedance that results higher efficiency.
At 100Hz, the flown TX-3A three-way main speaker takes over. The nominal dispersion of 50° x 50° focused perfectly to the dancefloor provides an extremely powerful and dynamic sound experience. Being a high priority, DJ monitoring was also incorporated into the acoustic concept. Here, Lambda Labs CX-2A monitors take care of the sound and an impressive SPL, even behind the decks.
Initial evaluation not only revealed immediately perceptible and audible changes, but also brought new challenges to the dancefloor that recently was open only occasionally – while the bar usually closed at 6am, the Tresor staff had to go out hunting for replacement DJs to serve the crowded dancefloor even after 10am.
More: www.lambda-labs.com
