Medieval Vaults and Contemporary Acoustics

In his 1998 book Musicking, the New Zealand-born musician Christopher Small makes a poignant observation. “I cannot remember seeing a concert hall built in Gothic style, possibly because its association with a mystical, theocentric culture is felt to be out of place in the rational, humanistic world of classical music.”¹ Indeed, one does not usually associate the performance spaces of classical music with Gothic architecture, unless perhaps the performance is embedded in religion. Yet in Ghent, a thirteenth century hall is one of Belgium’s foremost venues for classical music. However pointed the arches in the façade may be, its interior is dedicated mostly to the varied musical tradition of the more recent five centuries (give or take). Mediating masterfully between Gothic and acoustics is a contemporary architectural intervention by DRDH Architects and Julian Harrap Architects, with the acoustic expertise of Arup.

The problem of room proportions

Few audience members will suspect the challenges the design team was faced with, as today the concert hall serves its purpose with apparent ease. The elongated space pulls focus to the stage, its directionality amplified by a gradual incline of the seats. Audience and performers are united in a warm embrace of oak panelling, which lines the entire perimeter of the hall in the lower third. Its dark wooden tones and rhythmic expression echo an elaborate roof structure above. Its vaults are made up of two intersecting arcs, a formal theme reprised in the semi-circular curve in the panelling at each end of the hall. The layout is vaguely reminiscent of a church, although there is not even a trace of religious elements. In between the panelling and the roof, the walls are finished in clear white, completing a familiar composition. It all simply makes sense. And above all, the acoustics are impeccable. One can hear every last bit of detail in Beethoven’s Ninth from the back half of the hall (I can assure you).

However effortless it is all made to look today, the design brief was a challenge. The old hall is a medieval structure with major historical significance, but with a minor acoustic performance. The hall had obviously slanted stone walls and awkward dimensions. It is roughly four times as long as it is wide. Even the roof, a major redeeming factor in most regards, was actually quite low—limiting both acoustic performance and the stature of the hall. It was also highly complicit to the elongated character of the hall, as it defined the very same section profile over the entire length. It does not take an expert to understand that this spatial circumstance did not translate to perfect acoustic conditions.

Culture awakens in Flanders

These challenging conditions, however, did not stop music from being performed there way before the building was adapted to it. In fact the hall’s reputation as a classical music venue long precedes the most recent architectural intervention. The first concert was held in 1988, after the hall had been left abandoned. Before that, the hall was an infirmary to the thirteenth century Bijloke hospital and abbey, which expanded heavily in the seventeenth and nineteenth centuries. The older parts of the abbey were acquired by the city in 1913 (the year of the Ghent International Exhibition) to house a history museum that now operates under the name STAM. Meanwhile the hospital remained on site until 1983. Early musical initiatives were subsequently spearheaded by local enthusiasts and, combined with the unique atmosphere of the Gothic building, would eventually lead to its more institutional era as the primary concert hall in Ghent from the late 1990’s onwards.

This brief history of the Bijloke Concert Hall actually fits within a broader context of a cultural ‘awakening’ in the region of Flanders in the 1980’s and 1990’s with counterparts in art, fashion and architecture. That elucidates why this awkwardly dimensioned Gothic building has become a classical concert venue in the first place. To put it simply, the hall was empty and available at a time when cultural infrastructure in Flanders was being developed out of bottom-up initiatives. Since then, the venue has proven its merits and established its reputation as the place to be for classical music in Ghent, despite its less than ideal acoustic characteristics. This matter would be tackled later though, and it would be done thoroughly.

There are some decisive choices behind the harmonious whole that is the concert hall today. First of all, the floor of the existing building was given up to dig into the soil beneath. The increased height of the hall optimizes the spatial proportions and is a first factor in improving acoustics. But so is the variation in height, as the floor gently slopes from what used to be underground to the raised seats in the back. Of course, the slope also improves lines of sight for the audience and the overall orientation of the space. The wooden structure sits in the existing hall as if it were an oversized bath tub. The ends of the tub are curved and pushed towards centre of the hall to reduce its length. Behind the stage, the difference is made up mostly by raised choir benches and stairs to reach them. Depending on the concert the audience might sit here as well. Then still, square meters and hypothetical seats are undeniably lost in the new smaller footprint. All this, once again, for the benefit of spatial proportions and acoustics: Quality over quantity, after all.

Between presence and modesty

These bold choices should not detract from the level of detail on show as well. The oak panelling is refined yet modest, exuding warmth and solidity while adding yet another layer of acoustic refinement to the hall. Well hidden within are doors to the stage and the one-row gallery on each long side. The main entrances remain more clearly visible. They are on exactly the same level as the adjacent foyer, which in turn is connected to the outside without any steps, making the hall easily accessible. Above the stage, a final set of acoustic aids is suspended, along with lighting, from black steel arc that neatly align with the vaulted ceiling. All seats are upholstered in a greyish blue that contrasts ever so slightly with the wood tones around and above. Every single one of these design choices is present, but never intrusive.

Directly connected to the main concert hall is the former chapel, now the cloakroom. Mediating between inside and outside are and the foyer at the heart of the Music Centre and a café to the north. The interiors of both are designed by Studio Helder and Onbetaalbaar, with an emphasis on reuse of materials. In the nineteenth century south wing, an anatomical theatre can host more intimate concerts or lectures, while the beautifully renovated anatomical cabinet suits small events, lectures or even exhibitions. Somewhat hidden in the back is the ‘Kraakhuis’: a smaller infirmary from the sixteenth century, now equipped for chamber music.

The main merit in the project of DRDH and Harrap is perhaps this confident balance between presence and modesty. They recognized what qualities had made the hall appealing for classical concerts to the local music scene. This can be roughly summarized as a beautiful roof under which people enjoy classical music together. In their efforts to improve the experience they did not attempt to overpower the existing, nor did they let the existing overpower them. To put it in musical terms, their lower third is a harmonious counterpart to the melody that the medieval vaults had long established. After all, and as is true for music, good architecture is a matter of ‘listening’ as much as it is about ‘performing’. Especially when dealing with historic buildings and established cultural institutions – or, in this case, both.

The social aspect of music performance

Which brings me back to Christopher Small and his Musicking. The central argument of his book - as well as the point of its title - is to consider music as a verb rather than as an object. He takes a departure from classical music’s tendency to overly theorize. With abstraction, the social values and meaning of performance and listening tend to be overlooked. Small puts a lot of emphasis on the spatiality of music in this sense. As classical music evolved, so did its performance space, particularly the threshold between audience and performers. The design of these thresholds is interwoven with the design of performance spaces, directly informing the sense of exclusivity of the music being performed

In the Bijloke Concert Hall are definite signs of ‘inclusivity’. Some of the missing thresholds definitely are serendipitous, given with the historical building. For instance, there is literally no threshold to speak of between it and the surrounding campus – probably because of its origin as an infirmary. And the architecture is definitely Gothic and thus familiar - perhaps even revered. But it has no religious connotations. DRDH and Harrap seem to have picked up on this theme of minimal thresholds. Despite the slope they introduced, the perceived social distance between audience and performers is remarkably minimal. Both groups are quite literally put under a common horizon of the oak panelling. But most of all their design is atypically unpretentious for a classical music venue, yet dignified.

As classical music tends to be overtheorized, perhaps also stage architecture tends to be approached too much from an acoustical-engineering perspective. And acoustics do matter, as DRDH, Harrap and Arup have shown in Ghent. But what makes their work remarkable is that it shapes the social dimension of music – ‘musicking’, if you will – at least as much as its frequencies. – Petrus Kemme