Acropolis

Tisseyre + Associés has 40 years of experience in the acoustics of performance halls, its core business originally. Anticipating the turning point of digital and 3D visualization, we have developed a tool for 3D models of performance halls: Hall Acoustics^®, of which Acropolis was the first model. Instead of using the sound ray shooting technique which does not take into account the architectural details, we use the finite element mesh technique which allows these details to be modeled with finesse in order to fully integrate them into the acoustic performance. of the room from its conception.

Complete acoustic mission of the room

Thanks to our 3D model tool, Hall Acoustics^®, we can collaborate from the design phase with the architect in order to integrate the acoustic performance of the room into the architecture. Our work therefore does not focus on the dimensioning of a posteriori solutions of acoustic absorbers to attenuate the effects of reverberations. We work with the architect on the choice of shapes and materials used in order to optimize the reverberations so that they contribute to the acoustic performance of the room, which can be summarized as:

• Sound strength, clarity and definition. The sound should be loud, clear and precise.
• The Lev sound envelopment of all spectators. The people in the room feel like they are part of the show: the sound envelops them.

Tailor-made variable reverberation acoustic solutions

The integration of acoustic performance in the performance hall has led us to offer tailor-made solutions for the hall according to the variability of its uses. In order to optimize the acoustic performance of the hall for both symphony concerts and operas, we have designed removable ceiling hatches allowing a natural acoustic variability of 0.4 seconds. Thus, the reverberation time of 1.88 seconds (1 kHz), ideal for symphonic concerts, can be lowered to 1.7 seconds (1 kHz) by closing the hatches so that it corresponds to the optimal listening of an opera. In addition, in order to respond to the variability of the hall's uses, we have designed, together with the architect, a removable shell to accommodate 3 different gauges of orchestras. This room is the first room where L. Cremer applied his theory of staggered tiers allowing him to design the Berlin Philharmonic (1987). The acoustics of this hall remain today a benchmark in the world of concert halls.