The Grande-Duchesse Josephine-Charlotte Concert Hall

Urban context and form

Christian de Portzamparc was the winner of the 1997 international competition for the Philharmonie Luxembourg. Among the other candidates there were two other French architects, Jean Nouvel and Claude Vasconi, as well as others such as Mario Botta and Zaha Hadid, etc.

The Philharmonie, located on the Kirchberg plateau in Luxembourg - a new quarter between the airport and the old city, dedicated to European offices and institutions as well as culture - is deployed at the centre of the Place de l'Europe, which is a "square" of triangular geometry designed by Ricardo Boffil, who is in charge of the urban development plan.

The oval shape of the Philharmonie adds dynamism to the triangular Place whose urban layout it follows: its curved sides extend between two opposing corners which hug the borders, facing on one side towards the historic city and on the other side towards Boulevard Kennedy, a major thoroughfare through the Kirchberg plateau, expected to become a genuine urban avenue.

As a vast rotunda of curved walls, it highlights its independence and contrasts with the straight-line façades of the buildings surrounding it. The tension induced by the shape is further accentuated by the kinetic design of the façades, constituted by thin steel columns. On the north side, the Philharmonie borders along the front square space and falls back as if in gradual movement.

Response to the programme
The challenge of the competition was to bring together three major public exhibition spaces in one structure: a large philharmonic hall with 1,500 capacity, a small chamber-music hall with 300 capacity, and an open-air space to fit 120 spectators.

These spaces are provided with all the necessary living facilities:
- public reception: foyers, ambulatories, function rooms, video and audio tape library, bar,
dressing rooms, information, ticket offices
- rehearsal areas: strings, wind, percussion, soloists
- artistic staff reception: green rooms, dressing rooms
- technical staff reception
- management
- staff cafeteria
- logistics: transit, storage, workshop

The generously dimensioned reception areas placed on a sloped disc enable the audience to appreciate the space - which is simultaneously awe-inspiring, simple, and clear, and distributes the activities - in its entirety.

Underneath this disc, near the entrance, the infrastructure is organised into all the hall service spaces: transit, storage, rehearsal rooms with natural lighting, linked to the serving road provided alongside the Schuman building.

A frequent disadvantage with theatres and concert halls in cities is the exposition of closed, drab backstage rear façades, designed for deliveries. Here, all logistics takes place underneath, thanks to an overall slope of the entire public-reception level, which thus surrounds the entire hall in a vast peristyle. The Philharmonie's role as the heart of the place is therefore established, and its interior is an unending promenade.

The electroacoustic room is also underneath the disc.

The volume of the chamber-music hall sheltered under a "conical" surface appears to protrude from the chamber in the form of a coiled sheet.

Architecture - The Philharmonie and its peristyle
Entering the Concert Hall, into the world of sound and music, by crossing a curtain of light, is an experience that transcends the boundaries of the senses.

From the outside, the walls of the Concert Hall, made up of 823 parallel thin steel columns 17 m high, exude a gentle presence, alternately transparent or opaque. This "filter" façade offers glimpses of the interior that change according to the vantage point; it intrigues and attracts the passers-by to which it aims to appeal. Inside, it washes away the memory of the outside by imposing a light-filled space.

The walls, organised in a precise rhythm in several rows and intersected midway by a sheet of glass, vibrate like a musical partition developing along the arced lines of the façade. Some columns are load-bearing, some hold the glass, while others serve to distribute the air.

The Philharmonie is also a beacon in the city, whose light irradiates into the night outside, like a huge streetlamp.

The foyer gallery
Once inside the peristyle, the clear and mysteriously luminous inside wall of the columns and the folds of the central core appear, announcing the Grand Auditorium.

The folds of this core form a second façade, like an irregularly rhythmic cliff with large vertical fissures collecting the light from the midday sun during the day and coloured light during the night. The treatment of changing colour is one of the building´s peculiar traits. Christian de Portzamparc started this idea in 1986 with the conception of acoustic niches in the Villette hall and then in 1994 with the Bandaï tower and the play of colour diffraction on the façade relief. The interiors of the niches here are prismatic and, depending on the surface angles, the radiated colours differ continuously as a practical embodiment of this research started 20 years ago.

A ramp, bridges, and stairs coil around the Grand Auditorium, and make it possible to surround its height with access points to the hall's boxes.

Bars and an independent VIP lounge transform this space into a foyer for the audience.

The Grand Auditorium
The architect's major objective was to achieve the highest acoustic quality but also the highest aesthetic and functional quality for the hall. It is necessary to provide for a large volume in the knowledge that the control of sound reflection and diffusion is very delicate therein. The work is the result of volumetric concepts belonging to Christian de Portzamparc, tested and calculated by the acoustician Xu Yaying. Here, the architect repeated an innovative feature of the Villette concert hall: a high chamber with "occupied" walls.

Two layouts make this design optimal for acoustic quality:

1 - Creation of side walls near the orchestra and the stalls. This is a determining factor for the listening of the musicians and the audience in the stalls so that the initial sound reflections are quite short despite the large volume. The auditorium thus conforms to the "shoebox" type with its rectangular base in the widths and lengths recommended by the acoustician, but Christian de Portzamparc opens it up by giving depth to the hall above.

2 - This is about "occupying" the upper walls to render them living but especially because there is very good sound there and the musicians can feel those listening around them.

They are arranged over the base side walls with eight spectator-box towers for 28 listeners in each, with very favourable listening and viewing conditions thanks to the stepping of the levels and orientation according to slightly different angles giving each listener a good view towards the orchestra section. The irregular geometry of the towers enhances acoustic quality by alternation of diffusion/absorption, and by breaking up parallelisms.

The play of these independent towers suggests a depth that seems to expand the venue. Perception is no longer entirely of a closed chamber but that of lived-in constructions along the edge of a gathering place.

The Chamber-Music Hall
The architect designed this room as an uncoiling sheet, meeting up with the huge ellipse in the same movement.  Being sheltered underneath this twisted sheet - a cone section protruding from the column filter and being gently deployed - the volume of the chamber-music hall is very specific. The idea is a continuation of the research started in 1993 for the chamber-music hall of Nara in Japan, for which Christian de Portzamparc had explored the acoustic qualities of the Möbius band as a non-concentrating curved surface.  Inside, the hall is therefore determined by two diffusing walls with very tight forms over radiuses that prevent concentration of the sound.

A reflector above the orchestra area completes the layout. The hall axis unifying the orchestra with the audience is clearly defined and establishes the frontal ratio. The audience arrives through the top level of the hall and descends behind the orchestral shell along the wall. The orchestra goes below, linking with the lower logistical level.

The Open-Air Space
This open-air space for contemporary music, a place of spectacle and experimentation, must be especially flexible.

With a flat parallelepidic volume of 211 m2, it has a capacity of 120 people and benefits from all the stage equipment necessary for total modularity. Its specific position - underneath the disc near the main entrance - does not change the general shape of the whole. This third major space of the building developed on floors 0 and -1 is thus directly served by the logistical spaces.

The very nature of the space requires great acoustic vigilance with regard to the adjoining spaces, thus necessitating separation of the structure.