Set in the village of Andermatt in the Ursern Valley of the Swiss Alps, the Andermatt Concert Hall opened its doors on an inaugural concert performance by the Berlin Philharmonic in 2019.
The hall has seating for up to 650 and offers an intimate atmosphere with enough space for a 75-piece orchestra. The stage and lower level are below ground, and feature a high ceiling with upper-level walls of glass and wood, and a wrap-around balcony. Studio Seilern Architects tuned the performance space, integrating acoustic ‘origami’ panels. An enhanced acoustic system was also installed to increase the subjective sound level within the space for differing performances.
To address acoustic challenges, the venue brought in KahleAcoustics, specialists in space acoustics for concert and performance venues, and Amadeus Active Acoustics, developers of the Amadeus multichannel, active acoustic and immersive sound system. They were challenged to design and install a high-quality sound system that was both accurate and natural. To do this, the team used 75 CX41 loudspeakers and eight CX/CA118S subwoofers from Renkus-Heinz to cover the performers and audience.
KahleAcoustic Acoustician Associate Evan Green says that the challenge with a large orchestra in a relatively small space is how to control the sound level from being overwhelming. ‘Once you have a fixed volume, the way you make it quieter is to add sound-absorbing elements and surfaces,’ he explains. ‘But when you do that, the room becomes less reverberant, less resonant and the sound has less life to it, so we recommended a room enhancement sound system approach.’
This involves installing many loudspeakers that fully surround the audience to create an enhanced version of the hall’s acoustics. In the case of the Andermatt Concert Hall, the immersive sound processing system from Amadeus Active Acoustics uses 32 microphones to pick up all sound within the hall. Those signals are individually processed with natural active acoustic algorithms and then routed to the discreet Renkus-Heinz loudspeaker and subwoofer channels.
‘Our ultimate goal is that the performers and audience are never aware that any of this is happening,’ said Fabio Kaiser, Principal Acoustician at Amadeus Acoustics. ‘The space simply sounds like the natural acoustics of the room, but it’s created in a way that doesn’t add to the loudness issue. The natural acoustic character is still very present, and the scale of the room is expanded and enhanced by the active acoustics system.’
To support the programme loudspeakers, eight Renkus-Heinz CX/CA118S 18-inch, high-performance subwoofers were also installed. These provide the impact needed in many venues, and feature an accurate 35Hz to 100Hz frequency response.
‘It’s important for musicians to feel that they’re inhabiting the same space as the audience, so we need to make sure every direction is covered, and everyone gets sound from every direction, so they feel completely enveloped in sound,’ Kaiser says. ‘When you attend a performance at Andermatt Concert Hall, the system is on, but it just sounds like the natural sound of the room. Extremely high-profile musicians have performed here who been astounded by the active acoustics in place.’
Green agrees: ‘This turned out to be the best solution possible for this hall. We now have good speech intelligibility for conferences and banquets, as well as excellent quality, resonance, and an enveloping acoustic environment for classical music. I look forward to working on more projects with Renkus-Heinz products.’
