Vltava Philharmonic - competition proposal 4th place

DESIGN ARCHITECTURE
The design architecture is inspired by the Vltava River and its energy. The flow of water is transformed into the shapes of the halls in both the exterior and interior. All constructions and details of the building are subordinated to the inspiration of water flow.
The foyer of the main hall, with communication ramps, is open to a large window offering a view of the panorama of the historic city center, the Vltava River, and the silhouette of Prague Castle. At the highest point, an outdoor terrace is designed with a panoramic view.
The building features a guided tour circuit of the main components of the complex, with a view through a "triangular window" directly into the main hall and a perspective on the panorama of Prague and the Vltava River.
The viewing interior ramps serve as internal promenades, connecting the social spaces.

URBAN PLANNING SOLUTION
The "Pebbles" of the concert halls stand dignifiedly on a platform sloping towards the river. The platform serves as a magnificent public space with a café, terrace, restaurant, viewing staircases, and leisure meadows. Inside the platform, there is an entrance hall that is permeated by the curved shapes of the outdoor shells of the halls. The central hall is at the core of the free space, surrounded by service areas with clear entrances and visual connections.
The Philharmonic building is interconnected with the surrounding city. The design is intended to make it not only a cultural and social center but also, in a certain sense, a public space with the function of a square.

ACOUSTIC SOLUTION
Extraordinary care was given to the acoustic design of all three halls.
The layout of the "main" hall and "small" hall is designed as a "vineyard." The audience surrounds the stage from all sides to ensure good physical and visual contact during performances.
The shape of the auditorium is inspired by the flow of water, creating "streamlines" around the stage. The walls are carefully oriented and have a structured surface for optimal reflection of sound waves. The dimensions and shape of the hall take into account the uniform distribution of sound reflections in time and space. The proportions and chosen volume ensure adequate reverberation. The air conditioning is integrated into chambers under the seats and silently circulates fresh air throughout the space.
The acoustic design accounts for the optimization of early reflections in relation to reverberation to balance sound clarity and richness. The auditorium is steep for good sightlines and listening. The audience feels a close connection with the musicians and other spectators in the hall. The average height of the ceilings in the halls is 21 m. The height of the ceiling above the stage is approximately 14–15 m – above it is an acoustic reflector that allows for control of the delay and distribution of early reflections while maintaining a large volume. Shallow overhangs on the sides of the stage provide musicians with early reflections.
The multipurpose hall is designed separately as a so-called "black box." The height of the hall is 13 m. The walls and ceiling are equipped with acoustic shaping and panels of variable acoustics. The materials for the reflective surfaces are heavy (30 kg/m² for walls and 60 kg/m² for ceilings) and feature profiling of a depth of 10–50 mm.
Acoustic absorbers are evenly distributed throughout the space and designed to control a wide frequency range. This is complemented by the use of variable acoustic curtains or panels to ensure flexibility for various programs: concerts, recordings, dance performances... For flexible spatial arrangement, the design includes a stage elevation and a movable panel, allowing for the reduction or division of the room to optimize logistics between events.
Particular attention is paid to the acoustic solution in terms of noise and vibration insulation and regulation. The "Noise Criterion" value is NC-15 for the main and small halls, and NC-20 for the multipurpose hall and large rehearsal rooms.
Considering the risk of vibration transmission through the structures and external noise, several structural construction measures have been implemented. The halls are designed as "box in box" with a separate inserted structure, cushioned as well. The roof structure, surrounding floor structures, and communication facilities are placed independently.

SPATIAL AND OPERATIONAL SOLUTION
The complex consists of three parts:
PART I
The volumes of the halls are located on the "public platform." The large and small halls are connected to a common communication core and have immediate access to the backgrounds, rehearsal rooms, orchestra dressing rooms, and storage spaces for instruments.
The multipurpose hall is designed as a standalone structure to eliminate potential noise from different productions.
PART II
A compact base of the building with a public space "platform" on the roof. Here, the main entrance hall is centrally located, providing access to the three halls and other operations, service areas, dressing rooms, restaurants, and cafes. The entrance to the main hall is designed from all access directions.
At these levels, the building is connected to delivery ramps and a technical operational hub. There are spaces for administrative and operational support for the orchestras, dressing rooms, and rehearsal spaces, as well as the Philharmonic management.
PART III
Garages, machine rooms, and technical facilities in the backbone collector. These facilities are located in the lowest levels of the basement so that this horizontal transportation and technical infrastructure can logically and without conflict be connected by vertical corridors to the serviced parts of the building.

STRUCTURAL AND MATERIAL SOLUTION
The external structure of the halls is a reinforced concrete shell with an acoustic lining made of wooden slats in the interior. The halls have a "box in box" structure lined with wood. The structures of the halls are suspended from the base platform on which they stand. The platform itself is a reinforced concrete skeleton founded on piles. The surfaces are noble and visually appealing. The floors are made of wood, stone, cast concrete, and screeds, depending on their nature...
The material solution for the exterior is based on the basic architectural concept. Durable and solid materials are selected. The main structure is made of quality exposed concrete. The cladding of the main halls is made of glass-ceramic triangular tiles.
The viewing staircase of the terraces is designed in a combination of concrete and wood to allow for comfortable seating.
The interior materials are durable and noble (exposed concrete, glass, stainless steel, wood). The inserted halls are equipped with profiled cladding made of veneered wooden panels complemented by solid wood. The floors in the halls are wooden. The floors in the foyers are cast, coated, wooden, and in parts combined with stone.