Quietness, Comfortable Sound and Excellent Acoustics NAGATA ACOUSTICS


News 11-01 (No.277)

Issued : January 25, 2011

[ Japanese Version ]

Iwaki Cultural Center Main Hall Transformed Into a Concert Hall

by Ayako Hakozaki

Building exterior
Building exterior

Just two years after the first phase of Iwaki "Alios" Performing Arts Center held its grand opening, the fourth and final phase of this city's Private Finance Initiative (PFI) completed in the spring of 2010. The last phase renovated the city's old cultural center's main hall, transforming it from an outdated and worn multipurpose venue into a true concert hall.

<< Background and Aims of the Renovation as Part of the Alios PFI Program >>

The original Iwaki Cultural Center opened in 1975. The building occupies a convenient location that is a 10-minute walk from JR Iwaki Station and also a short distance from Iwaki Alios Performing Arts Center. Iwaki Cultural Center houses a main hall, a science exhibition hall, a teaching kitchen for the culinary arts, and general meeting rooms and exhibition galleries. In the decades since the center opened, many Iwaki City residents have come through its doors to participate in and enjoy a variety of events and activities.

Interior of the old hall
Interior of the old hall
Interior of the old hall

Among the center's facilities, the area of the main hall especially became outdated and worn over time. Iwaki City's residents wanted the main hall to be upgraded to current hall functionality and standards. The Iwaki Alios PFI program (featured in our May, 2008 newsletter) included this project as the last phase of its four-phase initiative.

The old main hall was a typical multipurpose hall with a proscenium stage. It had a single, sloped level of audience seating with 580 seats. The sound reflection panel system consisted only of panels at the rear of the stage and overhead.

The construction of Iwaki Alios Performing Arts Center and its second phase annex gave Iwaki City four new performance halls. Therefore, the PFI programming for the cultural center main hall specified that, as the city's fifth hall, the renovations should change this hall from a multipurpose venue to a concert hall specifically designed for music performances.

Iwaki Bunka Koryu Partners Co. Ltd, a consortium of multiple companies formed specifically to implement the designs and provide construction management services for all of the PFI's phases (as well as construction services for the first two phases) also designed and managed this renovation project. Kajiwa Corporation, which has its headquarters in Iwaki City, served as the general contractor.

<< Interior Structural Changes for the Transformation to a Concert Hall >>

The design objectives for this hall renovation specified in writing the goal of a feeling of oneness between the audience and the stage and, to achieve this goal, the removal of the old hall's reinforced concrete partial walls that hung from the ceiling at the proscenium. The renovation requirements also included installing new beams at a higher height as structural reinforcements. To implement the design objectives, we needed to gut the entire interior of the hall, leaving only the external frame, and build the hall interior anew.

While we could easily define the key changes needed to transform this hall from a multipurpose hall to a concert hall, we faced a number of planning and design challenges as we determined how to achieve the maximum ceiling height within the structure's limited space and create a feeling of oneness between stage and audience. As we developed answers to the room acoustical needs of the concert hall, it became clear that the project's stated requirement of changing the suspended partial walls and reinforced concrete trusses at the upper portion of the proscenium was also the key to answering the project's acoustical goals. These suspended wall portions at the proscenium restricted the height of the ceiling at the proscenium to just 6 m. (20 ft) above the stage floor, an undesirably low height for a concert hall.

In a room such as the Iwaki Cultural Center Main Hall that has large spatial volume, the structural considerations of changing the reinforced concrete trusses and suspended partial ceiling can surely be considered the project's most significant challenges. However, almost equally important was the development of a plan for temporary work, including determining the costs and other considerations involved in this portion of the project.

Reinforced concrete bearing wall (before renovation) Method of shortening reinforced concrete trusses and raise beam height at proscenium

Method of shortening reinforced concrete trusses and raise beam height at proscenium

Interior of the renovated hall
Interior of the renovated hall


<< Replacing the Suspended Partial Proscenium Walls >>

I included a photo of the old interior's problematic reinforced concrete wall with trusses. In our initial renovation design, we planned to entirely remove this wall and replace it with new steel trusses. Eventually, in the design we implemented, we decided to keep a portion of the reinforced concrete wall and the original trusses and remove only the bottom chord of the trusses (the portion shown as "A" on the drawing). The sequence of this work can be seen in the drawings with numbers (1), (2) and (3). First, we added a new, unifying reinforced concrete chord as indicated by "B". Then, after we confirmed the strength of the chord, we removed the portion of the trusses below the new chord.

While this change to the truss structure did not achieve the ceiling height that might have been obtained using our original full replacement design, we did achieve the significant ceiling height increase of 1.5 m. (5 ft). This renovation both raised the height of the ceiling above the stage and also enabled us to create a curved ceiling that connects smoothly from the stage to the audience seating area.

<< Other Changes to the Hall's Interior >>

As part of the renovations we also changed the design of the interior side walls so that they contributed to the feeling of oneness between the stage and the audience. In addition, along the lower portions of the stage and side walls, we specified the installation of a curved surface and a tile finish to create a diffusing wall surface that prevents the sound reflections from being too strong.

For the audience seating, we selected wider seating than was used in the old hall. The white ceiling and walls of the new concert hall combine well with the red floral pattern of the audience seating upholstery to create a visually bright and colorful atmosphere in the hall.

<< Highlights of the Concert Hall's Sound Isolation Design >>

The interior of the pre-renovation hall was connected by a single concrete structural layer to the hall exterior. In addition, an emergency exit led directly from the audience seating area to outside the building. The old hall's design did not provide sufficient sound isolation from noise generated outside the structure.

During the renovation, we added sound isolating wall material in the interior layer of the building's structure. As part of our sound isolation strategy, we also replaced existing doors with sound isolating doors.

Inside the building, we set NC-20 as the maximum allowable noise level for the hall's HVAC system. With this level of internal quiet and the external sound isolation measures in place, we achieved a quiet environment for the concert hall.

<< First Impressions after Completion of the Renovation Project >>

Many people who were familiar with the old hall said that the transformation so completely changed the hall that they could barely believe the new concert hall was once the old multipurpose hall. We designed this renovation within the constraints of the existing structure's framework, striving to come as close as possible to achieving a true concert hall. The project involved major reconstruction of some of the building's structural elements, and the project's success provides an example of a renovation that truly stretched the limits to transform a space into something very different than it was before the project started.


Announcing the "Save Casals Hall" Effort and Signature Campaign Appeal

By Dr. Minoru Nagata, Founder of Nagata Acoustics

Eight months ago, in the May, 2010 issue of this Newsletter, we shared the unfortunate news that Casals Concert Hall closed on March 31, 2010. Since its closure, the fate of this hall, which had the honor of bearing the name of the late master cellist Pablo Casals, continues to be a topic of concern discussed repeatedly in the classical music and organ music worlds. Many people continue to voice their desire for Casals Concert Hall to be reopened and, in response to these ardent appeals, a preservation movement came into being. The group spearheading this effort calls itself the "Save Casals Hall Committee", with pianist Shuku Iwasaki leading the committee's work. The committee aims to obtain one million signatures in support of the hall's preservation, and is focusing its efforts on people associated with the classical music industry who know the hall best.

<<Signature and Charity Concert Campaign to Revive Casals Hall >>

In addition to the signature campaign, the Save Casals Hall Committee has begun holding charity concerts to raise both funds and awareness. The first concert was held on Wednesday, September 1, 2010 and a second concert was held on Friday, December 2, 2010. The committee plans to continue the charity concerts at a pace of about one per month. The first two concerts and most of the planned future concerts are being held at Senkawa Avenue Hall in Chofu City, at the western end of the Tokyo Metropolis.

In addition to having pianist Shuku Iwasaki as the group's Chairperson, the Save Casals Hall Committee has Mrs. Marta Casals Istomin (Pablo Casals' widow) as honorary advisor. In addition, some 50 composers, orchestra conductors, musicologists, string instrument musicians, wind instrument musicians, vocalists, keyboard musicians and percussionists serve in volunteer capacities or have lent their support in other ways. The committee's mission statement reads: "We, a group of well-known music professionals, sharing strong affection for Casals Hall, join together in our appeal for the preservation of this famous hall that has so touched our hearts and where we have cherished memories and history. We fervently plead with you that somehow, some way, Casals Hall be kept alive."

<< Retrospective Symposium and Support from the Architectural Community >>

In addition to the above activities, on the evening of Tuesday, November 16, 2010, six music industry and architecture-related panelists participated in a special retrospective symposium held at Kitazawa Town Hall in Tokyo's Shimokitazawa neighborhood. Organized around the theme of the hall's value from the perspective of musicians and architects, each panelist spoke to the audience about performances and personal memories of Casals Hall, the hall's construction, architectural and acoustical features and the state of architectural preservation activities in Japan. At this event, Casals Hall architect Arata Isozaki voiced his support of the effort to save Casals Hall, giving us the promising step forward of having Japan's architectural community join with the music industry in the campaign to preserve the hall.

The symposium
The panelists at the symposium

Before and after the symposium, the three cellists Kou Iwasaki, Ryosuke Hori and Sayaka Hori, as well as pianist Shuku Iwasaki treated the audience to musical performances. They ended the evening with Pablo Casals' arrangement for cello of the Catalan folk song "Song of the Birds". About 200 people attended this symposium in support of the preservation of Casals Hall.

The symposium's six panelists were:
*Hiroyuki Suzuki, Architectural Historian and Aoyama Gakuin University professor
*Minoru Nagata, Acoustical Consultant on the Casals Hall project
*Shuku Iwasaki, Pianist and Toho Gakuen School of Music professor
*Tsuguo Hirono, Organist and Tokyo National University of Fine Arts and Music professor emeritus
*Shinichiro Ikebe, Composer and Yokohama Minato Mirai Hall Executive Director
*Koichiro Kanematsu, Architect and Kanematsu Architectural Design principal

<<Taking Action to Support the Save Casals Hall Effort >>

As yet unstated, but lurking in the shadow of the closure of Casals Hall is the possibility of the hall's demolition. I dread this eventuality primarily because it would mean the destruction of a treasure of music culture, and only secondarily because of my role in the hall's design and construction. I wish to do all I can to avoid this fate for the hall.

Currently, I can take two actions to support the effort to save Casals Hall. One action is to urge people to sign Shuku Iwasaki's petition to save the hall. The second action is to promote the monthly charity concerts held on behalf of the Save Casals Hall effort.

Individual and multi-signature Word documents can be found at the Save Casals Hall Web site, http://casals.us. Please print the forms, sign them and send them by e-mail, fax or regular mail to the addresses or fax number provided below. Also, for our readers in Japan, please make time on your calendars to attend the upcoming concerts. Here is the schedule for the first half of 2011:

Save Casals Hall Charity Concert Schedule January to June 2011

For more information about the committee's work, upcoming concerts and to reserve tickets, please contact the Save Casals Hall Committee by visiting its Web site at http://casals.us. The committee's phone number is +81-3-5314-9746 and the fax number is +81-3-5314-9759. The mailing address is: Save Casals Hall Committee, Senkawa Avenue Kita Plaza 2F, Senkawa-cho 1-25-2, Chofu City, Tokyo, Japan 182-0002. Thank you for helping me support this effort.


JATET (Theatre and Entertainment Technology Association, Japan) Forum 2010,
on the Occasion of the Association's 20th Anniversary

by Makoto Ino

JATET Chairman Ichiro Takada gave the keynote address.
JATET Chairman Ichiro Takada gave the keynote address.

Starting on Friday, December 3, 2010 and lasting two days through Saturday, December 4, the Theatre and Entertainment Technology Association, Japan (JATET) held JATET Forum 2010 at Owl Spot Theatre, a 301-seat theatre in the Ikebukuro section of Tokyo. JATET Forum 2010 celebrated two milestones: the 20th anniversary of the association, which was founded in July, 1990; and the association's new status as a "public interest incorporated association" ("koeki shadan hojin"), a step taken under new Japanese government rules for non-profits instituted in December, 2008.

<<A Brief History of Theatre and Technology Associations >>

Many countries around the world have theatre technology associations and most of these country-based associations connect with each other through the International Organization of Scenographers, Theatre Architects and Technicians (OISTAT). The start of OISTAT's predecessor organization, the International Organization of Scenographers and Theatre Technicians (OISTT) dates back to 1968.

A Japanese scenographer, Mr. Ichiro Takada, who now currently serves as JATET's chairman, attended OISTT's founding congress in 1968. He and other Japanese theatre technology professionals recognized the need for a Japanese association along the same lines as OISTT and founded Japan's first theatre technology association, the Japanese Institute for Theatre Technology (JITT), in May, 1969, one year after the establishment of OISTT.

In 1989, JITT disbanded. The following year, when some of JITT's formerly active members founded JATET, they expanded the scope of the new organization from JITT's narrow target of playhouse technicians and made it relevant to a broader range of theatre and stage technical professionals.

In the United States, the USITT (U.S. Institute for Theatre Technology) was founded in the 1960s. The USITT led the United States' development and widespread adoption of standards and work safety rules, such as the well known DMX (digital multiplex) standard for controlling stage lighting and stage digital communication networks. In 1987, a new U.S. organization, the Entertainment Services and Technology Association (ESTA) came into being to create a voice and forum for manufacturers and vendors of stage equipment and the technical professionals who operate and service the increasisngly sophisticated equipment used in theatres, halls and other entertainment venues. In Europe, the England-based PLASA (Professional Lighting And Sound Association) has been working actively since 1983.

All of these professional associations operate as non-profit entities, promoting the development of technical and safety standards within each of their countries and regions and serving as information hubs for their members. The associations' members include scenographers, theatre technicians, theatre architects, consultants (including acoustical, lighting and other consultants), stage equipment and systems manufacturers and vendors, stage construction companies, schools and other providers of instruction and training and governmental agencies.

<<Highlights of JATET Forum 2010 Presentations and Symposia >>

In 2001, the Japanese Diet enacted the Fundamental Law for the Promotion of Culture and the Arts with the aim of transforming Japan into a country where cultural and artistic activity has a firmly rooted presence. On the first day of JATET Forum 2010, Mr. Hirokazu Kadooka, Director of the Agency for Cultural Affairs, Cultural Activities Promotion Office, spoke to Forum 2010 attendees about issues the Japanese government anticipates will arise for arts promotion in the coming years. He also explained the government's key strategies and proposals for promoting cultural and artistic activities. Specifically, Mr. Kadooka said that the Japanese government expects Japan's decreasing population, combined with the country's difficult economic situation, to weaken some of the foundational supports for cultural and artistic activity. To counteract this expected trend and strengthen Japanese society's basic support of cultural pursuits and the arts, Japan's government proposes reorganization and refocusing of attention on public halls as centers of creativity.

At a symposium session on the first day, Mr. Tetsuo Kuwaya, Za-Koenji Public Theatre Executive Director reported on a local school program that follows an English educational model. This program targets the elementary and middle school students in Tokyo's Suginami City. The program engages the students in theatre arts activities that foster an understanding of the particular appeal of this performing art genre. The programs discussed by Mr. Kuwaya are based on the thesis that cultivating interest in culture and the arts by the youth of our society will create a sustainable source of cultural activities and support for the arts. The validity of this concept cannot be denied.

On the second day of the event, Mr. Oriza Hirata, a playwright and special advisor to the Japanese Cabinet, spoke to the gathering on the topic of "Organizational Structures for Public Theatres". Mr. Hirata introduced the Japanese audience to the collaboration methods used by public venues in France. He explained that the administrators of French public theatres involve themselves heavily in producing the performances held at their venues and that multiple theatres work together by contributing funding, human resources and their ideas and opinions to achieve high quality performances at their theatres.

During the forum's two days, the event hosted numerous speakers and symposia. In addition to the sessions I mentioned in the above paragraphs, the sessions included joint presentations with the Japan Theatre Directors Association about safety issues and there were opportunities to learn about new technologies and products. Overall, the JATET Forum 2010 provided a very satisfying program and I was glad that I attended the event.

For more information about JATET, visit the association's Web site at http://www.jatet.or.jp/



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[ Japanese Version ]