Underground overtures

The new concert hall designed by Studio Seilern Architects for a Swiss ski village evolved from humble subterranean origins into a striking composition, opening up the building to the world’s leading orchestras. James Parker reports

Andermatt is a small ski resort village of around 1200 inhabitants nestled in the Swiss Alps – a former military outpost located at a historically important crossroads of strategic routes across the mountains. However, the village’s light had dimmed significantly in recent decades, paling in comparison to other Swiss resorts. After the military pulled out several years ago, the municipality wanted to ensure Andermatt did not decline further, and decided to invest in its future.

The latest example of Andermatt’s redevelopment is a world-class concert hall designed by Studio Seilern Architects, which puts the village on the map as a musical as well as holiday destination. It also does so in a surprising and stealthy way that harnessed the practice’s proven design ingenuity in cultural sector projects. This is a building mostly submerged in the earth, originally destined to be a subterranean conference room for the town’s new Radisson Blu hotel, until practice founder Christina Seilern had the vision to do something very different.

While the project began life as an enclosed building, its evolution into something far more ambitious is characteristic of many schemes the architect has worked on. She tells ADF: “It’s a bit like story writing, you put in the major points you’re trying to achieve, but it really takes you on an adventure.”

The project’s origins were when the Swiss Government approached Egyptian developer Samih Sawiris, who has a reputation for transforming places with scarce infrastructure or built assets into major holiday destinations. He restructured the ski lifts, and built hotels, including the stunning five-star Chedi Andermatt. Sawiris is also a “very passionate music buff,” says Seilern, explaining that her involvement began when she met Sawiris while designing two restaurants near the town: “He was talking about wanting to do a concert hall, and didn’t realise one of the things we do is performing arts!”

It was not only Sawiris’ love for classical music that made him want to pursue a grander vision for the hall – then under construction as a concrete basement next to co-client Radisson’s hotel – but also pragmatism. He was aware that a small resort couldn’t rely on seasonal sports, says Seilern: “it needs to be an all-rounder.” Creating a concert hall of a standard that would attract the world’s best orchestras (including perhaps the most famous, the Berlin Philharmonic) would help make Andermatt generate revenue throughout the year as a destination.

Site & design solution

The site is in the centre of the village, however it’s in an “unexpected niche,” says Seilern, adding, “normally a concert hall is on the main square.” It’s in fact located behind the Radisson Blu hotel, but the architect’s solution has ensured it presents an intriguing face to the local community.

Studio Seilern lifted and extended the existing steel roof (which would have made the ceiling only around 6.5 metres high) well above grade, increasing the volume from around 2,000 m3 to 5,340 m3. This enabled the building to host a full 75-piece symphony orchestra, and to seat 663 in the auditorium with the help of a concrete ‘backpack’ added to provide an upper gallery of seating. This addition also required magnanimity from the architect of an adjacent hotel, who had to redesign the scheme to give room for the extension to the concert hall.

With the client having strong ambitions to attract the leading orchestras, the design team toured other concert halls, including the flexible new space by Frank Gehry for pianist Daniel Barenboim’s Barenboim-Said Akademie in Berlin. This has a similar size in plan to the Andermatt Concert Hall, but is 12 metres high; Seilern says “it’s pretty obvious when you’re in there why you need that height.”

The big increase in height obviously meant a considerable uplift in cost (the project ended up costing 16m CHf), and the client needed careful convincing this was in line with their ambitions. Seilern explains how canvassing the views of the musicians who would use the space was essential: “What helped us enormously was not us telling the client, but the musicians, that was what really unlocked the project. They said ‘we’re not going to play in that little hall.’”

The continuously glazed upper level, peering above the ground, allows people walking past to have a glimpse down into the hall – and three pale, cloud-like acoustic fiberglass sculptures – and even to see an orchestra playing below. The full-height glazing also brings in copious natural light, as well as views of the surrounding mountains, into the hall itself. The architects explained: “The romantic idea was that if it was a winter concert, the audience would be surrounded by a whirlwind of snow, and in the summer surrounded by nature and sunshine.”

This “active frontage” turns the building into a “spectacle” externally, says Seilern, and internally marks it out among other concert halls, which tend to be somewhat closed off from their surroundings for acoustic reasons. Here full-height glazing runs continuously around the above-ground portion, underneath the roof, whose timber-lined overhang is deep enough to create a public plaza beneath. The glass has been specified according to the acoustician’s requirements to deal with 50 dB, and actually contributes its reflective properties usefully to the space.

Christina Seilern’s very first sketch for the scheme, informed by her knowledge of designing other concert halls, included three suspended acoustic sculptures in the hall. Although this scheme progressed to a single form at one point, it has ended up with something very similar to her intuitive vision – partly due to pragmatic concerns around needing to hold water in a single sculpture for sprinklers. Winches enable the three final forms to move up and down as required for different performances. With a world-class concert hall, Seilern explains, it is not a finished article at completion, “you are constantly tuning it.” She adds that the designers are gathering feedback from musicians, and return with the acousticians to tweak design elements.

Seilern describes the careful process which led to choosing the final glazing surrounding the sculptures, but which also provides the upper face of the concert hall itself: “We had to test it at different sound frequencies because the acoustician wanted 50 dB at certain sound frequencies but not others, and had to work with the manufacturer to get the right kind of glass.”

The solution of a triple-glazed operable facade with a single insulating layer “completely opened up the whole project and liberated it,” says the architect. “It made it transparent and light, it didn’t feel like a clunky, complex facade.” This was a major improvement on the “hugely complicated triple-layer facade” that was initially proposed, says Seilern. This was expensive but also had issues around transparency. An electronically-controlled curtain closes across the glass to enable conferences or evening parties to take place in greater privacy.

Acoustics & staging

The undulating ‘origami-like’ ceiling and wall design was devised by the architects working closely together with Kahle acoustics to create the best possible sonic results; in so doing it also provides an appealing visual geometry. The strips of white oiled oak, arranged in a pattern of triangular sections, are thinner as the building rises, and subtly change from something closer to white to a yellower shade.

“Everything has been angled for the ideal acoustic reflection,” says Seilern, adding: “It’s like an instrument, you are designing an instrument for the orchestra.” The interior has been painstakingly designed to optimise reflection and absorption from orchestra to audience in the right places, and the calculations have resulted in interesting forms such as the inclined balconies. The dynamic interior, with views up to tree-covered mountains, enhances the entire experience to an immersive level, helped by the suspended reflectors designed to achieve the perfect auditory balance.

The ceiling is striped with “technical strips” which discreetly house smoke detectors, lights and around 260 speakers and over 120 microphones – for the PA system. The building is designed for an orchestra to require no audio assistance, but does have an ‘electro-acoustic’ system to slightly increase reverberation time to optimise acoustics for larger orchestras.

Due to planning restrictions on the site, only some of the roof could be raised, this meant that the original configuration of the stage area would have been awkwardly constrained. So the designers placed the stage in the centre of the hall instead, giving symmetry to the space as well as acoustic benefits. This is enhanced by the two elegant pairs of angled white steel columns, framing the stage and reappearing at the ground floor entrance to support the roof.

Christina Seilern comments on the stage design: “It creates an acoustic pocket for the orchestra to sit in – to me what was really important was to sit the audience around the orchestra and envelop it.” She says that when the space is this intimate, and if you “wrap people around the orchestra,” everyone “has a good seat,” in terms of both visuals and acoustics. In addition, the central stage position means the foyer is a ‘crossover space’, which can be used by the orchestra during performances.

Behind the stage is a wall of expanded aluminium, designed to provide acoustic reflection in certain areas to help the musicians hear themselves. In others however it is more transparent, providing absorption, so that players of louder instruments don’t overwhelm themselves. Behind this sits air exhaust ducting – one area where the heavily serviced space discreetly accommodates its copious M&E plant. The hall is flexible – a stepped platform of up to nine rows can disappear under the main balcony to create space for events.

The building is designed to strict Swiss ‘Minergie’ energy efficiency standards, however with it being completely shaded by nearby buildings, solar gain was not a concern. What was a challenge was accommodating the M&E services required without any acoustic interference; this meant a redesign of the original services strategy with bigger ducts and lower velocities. The timber-faced balcony’s deep form not only attenuates, it also hides what Seilern says are “enormous” ducts, which vent conditioned air from openings underneath the seating.

Foyer & entrance

The entrance is a small, round pavilion that was already built as part of the hotel, with a door added by the architects for off-street access. Once inside, visitors descend the “origami well,” as Seilern describes it, down a stair, whose pre-existing concrete core now houses the foyer. A mezzanine gallery was added here to provide added space for bars and circulation, and the golden polycarbonate and metal wall continues the pattern of triangles, which is repeated throughout the building.

“Because it is underground, we wanted to create something that was very reflective and would bounce the light around; we were fighting this bunker effect,” says Seilern. While some natural light descends via the staircase, the wall, inspired by Alpine glaciers and rock formations, helps the area feel light.

The clients have ensured that the local community feels included, and indeed has a sense of ownership of this prestigious new venue. “They release tickets, and during construction they were taken around the site, and had a video done for the opening – they are incredibly proud, that it’s the first of it’s kind.” While there have been other classical music festivals in Swiss ski villages, this is the first to have a concert hall, and three festivals are currently planned for Andermatt.

Conclusion

“When a new hall opens, the musicians decide what’s right and what’s not,” says Christina Seilern. Following the showing of the project to musicians to ascertain their views in the project’s initial stages, the architects found they were able to harness their expert ears in persuading both client and themselves of the need to both expand the space and rigorously detail it so that it performed in the best possible way. As a result, the finished building is proving very popular with its knowledgeable users, who in turn are able to perform at their best for paying audiences.

The building was opened in June last year with a concert by the renowned Berlin Philharmonic Orchestra. Although the ultimate demonstration of the light-filled, acoustically honed hall’s success, it was a nerve-wracking test-run for the architects. Seilern says: “It was quite daunting, because they are the critics at the end of the day.” However, she reports that the musicians were “very happy” with the space, and only made some technical comments regarding artificial lighting, “which is fine, we can solve that.”

Since opening, Seilern says musicians who have performed at the hall “are thrilled to see they have a new instrument to play with.” Its intimate nature is also a refreshing change for many performers, used to playing in cavernous 12,000 seat halls. A musician at the opening told the architect they were close enough to see an audience member had been moved to tears – a powerful demonstration of how this building can provide orchestras as well as audiences with a rare experience.