News 17-02 (No.350)
Issued : February 25, 2017
Elbphilharmonie Opens in Hamburg / Special Edition
By Dr. Yasuhisa Toyota
<< The Opening >>
In Germany’s second largest city, Hamburg, the new concert hall venue Elbphilharmonie opened on January 11, 2017. Historically, the city of Hamburg developed as a port and commercial city on the Elbe River that connects the port to the North Sea. Facing directly on the Elbe River, in a district where old warehouses faced the river and that has become one of the most significant parts of the city, the Elbphilharmonie concert hall now stands prominently on the waterfront. Hamburg is a city rich in classical music associations, being the birthplace of Mendelssohn and Brahms and the sometime home of many famous composers, including Telemann and Mahler among others. It is also the city where Steinway & Sons manufactures its pianos.
(from Elbphilharmonie Website)
A full 14 years elapsed from the inception of the Elbphilharmonie project in 2002 to its January, 2017 opening, and 12 years have passed since Nagata Acoustics joined the project in 2004. Compared with projects of a similar type and scope in which I participated, Suntory Hall took 6 years to reach its completion in 1986, and Disney Concert Hall (in Los Angeles) took 14 years from its beginning until it opened in 2003.
Elbphilharmonie and Disney Concert Hall each encountered a hiatus due to special situations that stopped progress on those projects for a period of time. Even in the best of circumstances, a major concert hall cannot be simply completed in the 2 or 3 years that are sufficient to construct an office building or residential housing.
On a concert hall project, even if every part of the process proceeds smoothly, it can be expected that the shortest possible schedule needs 2 to 3 years for the design phase and another 3 years for construction. Add to this several months to 1 year for planning and conceptual design at the beginning, and at least several months of post-construction opening preparations, and 7 years becomes the minimum time needed to complete a new concert hall from the start of the project to the hall’s opening. At the beginning of concert hall projects, the project duration and costs are often not sufficiently budgeted, but instead begin with overly optimistic schedule durations and financial budgets. If this wasn’t the way things happen, it seems that some projects would not get started in the first place.
<< Architectural Design and Acoustical Design >>
The building that houses Elbphilharmonie has 26 stories and a total floor space of 120,000 sq. m. (1,300,000 sq. ft). The building comprises a 2,100-seat "Grosser Saal" (Large Hall), a 500-seat "Kleiner Saal" (Small Hall) and ancillary spaces, as well as a hotel and condominiums. At the height of the eighth floor, the building offers incredible 360-degree vistas of the city and the Elbe River. On this level, a Plaza offers access to the general public and also serves as the entrance to the "Grosser Saal" and "Kleiner Saal" built on the floors above the Plaza.
We designed the "Grosse Saal" as a concert hall for classical music and we planned the "Kleiner Saal" as a multipurpose hall with the focus primarily on chamber music and appropriate acoustics for a wide range of performances and events such as popular music genres, drama and lectures. The Swiss architectural firm of Herzog & de Meuron created the Elbphilharmonie project’s architectural design. Hochtief AG served as the general contractor. Nagata Acoustics provided all acoustical consulting services to the project from the design phase through construction and project completion.
The design of the concert hall’s room acoustics might be summarized as comprising 2 important areas, the “room’s shape” and the “room’s interior design materials”. Of course, consideration of the concert hall’s shape includes both the major elements of ceiling height, room width and overall layout, and also such details as surface variations along the ceiling and walls—that is, every visible element that has a specific physical shape. The concert hall’s interior design materials include not only the materials and finishes that are visible to the eye, but also the structure and properties of the underpinnings and backings of every interior element. The room acoustics design must address all of these elements, but it is also true that the same elements—the room’s shape and its interior design—are the focus of the architectural design. Therefore, designing the interior of a concert hall needs to be a single collaborative process of the architectural and acoustic designs.
In approaching the design of Elbphilharmonie’s interior, we identified the concept of “intimacy” as our keyword. From both the architectural (that is, visual) perspective and the acoustical perspective, we sought to achieve “closeness”. Because of the size of "Grosser Saal", the question of how to make the audience feel “not distant” from the performers became the most important theme of our design work. When Nagata Acoustics joined the project design team, the project had already decided that the basic shape of "Grosser Saal" would not be the “shoebox” configuration, but instead, would use the so-called vineyard configuration to seat the audience as close to the stage as possible.
For our room acoustics design, achieving acoustical “intimacy” most importantly meant how to obtain effective and valuable early sound reflections and, to do this, how to create acoustically effective walls around and in the vicinities of the sections of audience seating. Our design solution involved creating small groups of audience seats and designing effective, sound-reflecting wall surfaces for every group of audience seating.
<< Acoustical Testing >>
Critical assessments and judgements about the excellence or failings of a concert hall’s acoustics do not come from people reading data sheets with reverberation time and other numerical measurements of physical properties. Ultimately, individuals seated in audience seats listen to performers playing music on the stage and the audience, by listening to the music, evaluates and judges the acoustics.
It might be thought that the acoustical consultant attends a hall’s opening night performance as if “sitting on pins and needles” with tense concern about how the acoustics will be received, but this is not accurate. Usually, the most tense moment for the acoustical consultant occurred months before the opening night, at the first rehearsal held in the hall. This is also arguably the worst time to test or judge the acoustics of a concert hall. The reason is that the performers are unfamiliar with the hall’s acoustics, do not yet know how their playing will sound in the hall and do not yet know how to listen to the music of their fellow performers, so the first rehearsal in the hall almost invariably begins with fumbling around in the new environment.
The first rehearsal in the hall is the worst time to test the new hall’s acoustics. The time that the ensemble’s musicians spend listening to each other and creating the ensemble’s special sound is all in the future. If the first rehearsal is the worst time to test the hall’s acoustics, the second rehearsal is always an improvement over the first rehearsal and at the third rehearsal we always hear how things are improving and coming together. When I am asked how long should the rehearsal period be in a new concert hall before the official opening, my instinct is to answer “as long as possible”. But while I would be delighted for ensembles to spend years rehearsing in a hall before their first public performance, I know that this would be an unrealistic answer. At a minimum, an ensemble should spend 2 to 3 months rehearsing in its new hall and, when possible, rehearse for 6 months in the hall before the hall officially opens. In keeping with these guidelines, the Elbphilharmonie project schedule gave the NDR Elbphilharmonie Orchester 4 months of rehearsal time in the new "Grosser Saal" before opening night.
<< Orchestras and Concerts beyond Opening Day >>
"Grosser Saal" Grand Opening
It was decided from the planning phase of the Elbphilharmonie project that the new hall’s resident orchestra would be “Norddeutscher Rundfunk (NDR) Symphoniker” (the North German Radio Symphony Orchestra). For the orchestra and the hall, the resident orchestra’s relationship to the hall refers to something other than a commitment to perform a subscription concert at the hall on a monthly basis. For Elbphilharmonie and its resident orchestra, the resident orchestra relationship means that the orchestra will use the "Grosser Saal" stage on a daily basis to rehearse. The orchestra and the new hall will develop together with the hope and expectation that the orchestra will become the “face” of the new hall. One way that the NDR Orchestra revealed how deeply it understands its role and new beginning has been through its renaming of itself to its new name of "NDR Elbphilharmonie Orchester".
In addition to performances by the "NDR Elbphilharmonie Orchester", the city’s other orchestras: the Philharmonic State Orchestra Hamburg (which plays under the name Hamburg State Opera Orchestra when playing in the Hamburg Opera House pit), and the Hamburg Symphony Orchestra will both move their monthly subscription concerts to Elbphilharmonie. However, while both of these local orchestras will hold monthly performances at Elbphilharmonie, they will use the hall only on the days of their performances and will rehearse in other locations. In this way, their relationship to the Elbphilharmonie differs significantly from that of "NDR Elbphilharmonie Orchester".
In addition to performances by Hamburg’s 3 local orchestras, an impressive array of invited musicians and ensembles will come from around the world to give concerts at Elbphilharmonie. The organization responsible for planning the new hall’s calendar of guest performers is "Hamburg Musik", which is an agency of the Hamburg municipal government and the same organization responsible for the Elbphilharmonie’s daily operations and maintenance.
The official opening of Elbphilharmonie marked the accomplishment of the goals of an incredible architectural project. At the same time, for "NDR Elbphilharmonie Orchester" and the "Elbphilharmonie, Hamburg Musik" organization the hall’s opening is the first milestone of a new era of future musical accomplishments and possibilities.
Highlights of Room Acoustics and Sound Isolation Design
By Dr. Keiji Oguchi
<< Designing the Room Acoustics of "Grosser Saal" >>
Acoustic test with 1/10 scale model
Micro-shaping on the ceiling at "Grosser Saal" for sound scatter
Acoustically transparent wall in front of the pipe organ
Entering the Elbphilharmonie "Grosser Saal" from the dynamically flowing and smooth lines of the lobby’s interior surfaces, what first impresses the eye is the sudden change to a room of intentionally uneven, textured wall and ceiling surfaces. The surface micro-shaping of the walls and ceiling create a visual design with a seashell motif and serve the role of promoting acoustical diffusion for the hall’s acoustics. From the surfaces of the walls and ceiling we can expect the soft reflections and, in addition, these surfaces dissipate and eliminate any undesirable localized echoes that might otherwise occur.
The audience seating blocks and ceiling height, as well as the placement of a hall’s walls determine how reflections reach different locations within a hall. To study these basic shapes in the "Grosser Saal", we began by using computer simulation based on the geometrical acoustics to study how the reflections would distribute in the "Grosser Saal". With these studies we had intensively discussed about the basic room shape with the architect.
In the next phase of our room acoustics design after fixing the basic room shape, we built a 1/10 scale model of the hall interior and conducted acoustical experiments in the scale model to study more details about how sound would behave in the space. Our first step in scale model testing was to check for detrimental echoes and, if an echo was found, to solve how to eliminate it. In halls such as Elbphilharmonie’s "Grosser Saal" that have the vineyard (also called “arena”) shape, sound can easily return back into the room as a long path echo (a strong reflection with a long time delay). Our tests in the 1/10 scale model of the "Grosser Saal" found long path echoes at the stage and nearby seating. In the case of a long path echo, the options to eliminate it are: changing the angles of some reflective surfaces; adding sound absorbing measures; or adding diffusing elements. The architect favored diffusion to eliminate the long path echo as one of diffusing surface patterns which were usually expected to create soft reflections.
To test and confirm the efficacy of the seashell motif surface, we made a 1/10 scale version of the seashell motif surface and affixed it to the portions of the wall in the model that had caused the echoes. We also used scale model testing to determine the depth of indentations necessary to achieve our desired results.
In the project’s "Grosser Saal", the diffusion wall material was fabricated from gypsum board that is fiber reinforced to have relative density of 1.5. The fabrication process involved bonding together multiple layers of gypsum board panels and then sculpting out the surface in the seashell motif pattern. In the locations where we expected the surface producing soft reflections, the depth of indentations for diffusion measures 10 to 30 mm. (0.4 to 1.2 in.). Where we aimed to eliminate echoes, the depth of indentations for diffusion measures 50 to 90 mm. (2 to 3.5 in.). Also, because we needed these panels to have sufficient weight to effectively reflect sound even at low frequencies, the panels were fabricated so that they have a post-sculpting average density of 125 kg/sq. m. (25.5 lbs/sq. ft).
The seashell motif material is used entirely on the walls and ceiling of the "Grosser Saal". The 3D modeling was used to determine where to place joints in the panels of this material and then the panels were fabricated at an off-site factory. In addition, the flat panels of the same gypsum board material for the "Grosser Saal"’s flooring substrate over which the wood flooring was installed.
<< Audience Seating of "Grosser Saal" >>
Our primary requirement for the audience seating in the "Grosser Saal" specified that all surfaces be acoustically reflective except those that would be covered when a person is in the seat. This meant cushioning and upholstering only the front of the seat back and the horizontal seat, and using wood paneling for the rear side of the seat back. The unique design of the seating creates a visually smooth transition line between the seat and seat back when the seat is in the raised position. The seat’s upholstered fabric is attached directly to the rigid panel of the seat’s rear side.
In particular, because the seat cushions of the audience seating are thick, when we tested the seating in a reverberation room, we learned that its equivalent sound absorption area is a rather large value of slightly greater than 0.3 (at mid-range frequencies and with the seat vacant). However, when the seat is occupied, the equivalent sound absorption area is less than 0.4, which means that the difference between a vacant and occupied seating is quite small.
<< Interior Finishes of "Kleiner Saal" >>
Micro-shaping on the wall
at "Kleiner Saal" for sound scatter
Our acoustics design of the "Kleiner Saal" both prioritized the hall’s use for recitals and, at the same time, gave strong attention to its use as a multipurpose hall. The room’s tiered floor can be stored behind the hall’s rear wall using a pneumatically powered mechanism, making it easy to convert the room to a flat-floored space for events and receptions. Also, the walls of the "Kleiner Saal" have absorbing banners that can be moved up and down like roller shades to vary the room acoustics for the needs of a different kinds of events.
For recital and chamber music use, we gave the walls of the "Kleiner Saal" an intentionally uneven surface treatment that promotes diffusion, as we did for the "Grosser Saal", but we used different materials to achieve this. In the "Kleiner Saal", we fabricated the walls of laminated wood with cut-out patterns that achieve the desired uneven surface treatment.
For sound isolation reasons, which I explain in a below paragraph, the hall’s structure has a box-in-box concrete design. We kept the concrete ceiling of the “inner” box as an exposed concrete ceiling (with a black paint finish) in order to effectively utilize the hall’s limited ceiling height.
<< Sound Isolation to Address Ship Whistles >>
Ceiling structure and spring at "Grosser Saal"
Inner box (shotcrete) for sound isolation at "Kleiner Saal"
Large ship passing by "Grosser Saal"
For Elbphilharmonie’s architectural design, the architects kept the old brick warehouse facade that stands directly at the waters’ edge of the Elbe River and constructed the new halls on top of the old facade. The Elbe River functions as an active seaport for large, ocean-going vessels and ship terminals line the waterway on the east side of the Elbphilharmonie building. The berths accommodate large ships such as the Queen Mary 2 (weighing 76,000 tons) and other cruise liners.
When a cruise liner leaves its berth for a voyage, it blows its ship whistle. The sound of the whistle can be heard even several kilometers away in downtown Hamburg hotel rooms. Ship regulations require that the larger the ship, the lower the frequency of the ship’s whistle. In the case of the ship whistle of the Queen Mary 2, we needed to achieve sound isolation of ISO R’w (weighted sound reduction index) rating of 90, and 75 dB isolation at 125 Hz octave band. To achieve this high level of sound isolation, we adopted a building anti-vibration system using metal springs that can be set to a lower natural frequency than is possible using anti-vibration rubber material. Our goal with this design was to achieve more effective sound isolation at lower frequencies than can be achieved with rubber sound-isolating materials. Specifically, the both Halls structure has a 200 mm.-thick (8 in.-thick) concrete outer box (made of half-precast concrete) and, inside of this box, an inner concrete box, also 200 mm.-thick (a shotcrete deck structure) supported on the metal springs. The both Halls’ interior was constructed inside this inner box concrete structure.
The natural frequency of our design is 3.5 Hz. The springs used in this design can be compared to the rubber bearings used in a seismic isolation structural design. However, because rubber bearings are designed to dampen the effects of horizontal shaking, they are comparatively stiff in the vertical direction, while the building anti-vibration springs in Elbphilharmonie are flexible in both the vertical and horizontal directions.
In July, 2016, we visited Elbphilharmonie before construction completed and tested our sound isolation solution by measuring and listening to a large ship’s whistle. We confirmed that we could hear the whistle when we stood sandwiched between the "Grosser Saal"’s outer concrete box and the inner box. When we stood next to the small window facing to the river in the hall, we could not hear the whistle’s sound. We breathed a sigh of relief to have confirmed the success of our sound isolation design.
<< Acoustic Parameters According to ISO 3382-1 >>
The following values were measured using the methods of ISO 3382-1: 2009 Acoustics - Measurement of room acoustic parameters - Part 1: Performance spaces.
Nagata Acoustics Inc.
Hongo Segawa Bldg. 3F, 2-35-10 Hongo
Bunkyo-ku, Tokyo 113-0033, Japan
Tel: +81-3-5800-2671, Fax: +81-3-5800-2672
1990 S. Bundy Drive, Suite 795
Los Angeles, CA 90025
Tel: +1-310-231-7878, Fax: +1-310-231-7816
75, avenue Parmentier
Tel: +33 (0)1 40 21 44 25, Fax: +33 (0)1 40 21 24 00