Quietness, Comfortable Sound and Excellent Acoustics NAGATA ACOUSTICS

News 11-04 (No.280)

Issued : April 25, 2011

[ Japanese Version ]

Yokohama's Tsurumi City Cultural Center (Salvia Hall)

By Akira Ono

Artist's rendering of the Sea Crane complex
Artist's rendering of the Sea Crane complex

On Saturday, March 5, 2011, Tsurumi City Cultural Center (named Salvia Hall) held is official opening, adding a new cultural and entertainment attraction to this part of Yokohama, conveniently located in front of JR Tsurumi Station.

<< Project Overview >>

The Salvia Hall project completes a larger redevelopment plan by Japan's Urban Renaissance Agency on land adjacent to JR Tsurumi Station that was previously used by the JNR Settlement Corporation. In addition to the cultural center, the redevelopment program built a hotel to be managed by JR Group, a 31-story apartment tower, childcare facilities and space for shops and offices. All the buildings except the cultural center opened in October, 2010, five months earlier than Salvia Hall. The redevelopment plan also includes enlarging the plaza in front of the train station and a complete makeover of the station house. These last changes are still in progress.

The project planners sought public input on names for the overall redevelopment program and the cultural center project. From among the suggestions received, the decision makers chose "Sea Crane" for the overall complex and Salvia Hall for the cultural center. The name Sea Crane echoes the city name of "Tsurumi", which is written with two Chinese characters, one that refers to the bird "crane" and one used as the root of the verb "to see".

The redevelopment program's key participants included Ishimoto Architectural & Engineering Firm, Ltd for the basic architectural design, P.T. Morimura & Associates for the mechanical equipment and systems design, Arts Space Factory as the stage consultant and Nagata Acoustics in the role of acoustical consultant. After the completion of the basic architectural design, Takenaka Corporation became responsible for completing the project's construction drawings and also served as the general contractor. For Salvia Hall, the design team continued its participation and oversight to ensure the project's implementation of the design objectives and manage the interior installation.

<<Sound Isolation Design >>

Because the project site sits sandwiched between the JR Keihin Tohoku Line Tsurumi Train Station and the Keihin Express Line's train station, we began our work on the project with the assumption that noise and vibration at the site would require serious attention. As an input to our design strategy, we conducted on-site studies of the noise and vibration levels while the land was still a vacant lot. Based on the information we obtained we decided that noise and vibration structural designs would be needed both for the overall structure and for each room of the Salvia Hall Cultural Center.

The first stage of implementing our sound isolation plan began with an assessment of the need to adopt an underground anti-vibration structure below all of the buildings planned for the site, including the high rise apartment tower. Our design specified the use of cushioning material in between the soil-mixing cement continuous wall system (diaphragm wall) and the buildings' underground structural system.

In addition, for the multipurpose hall, music hall, three practice rooms and rehearsal hall of the cultural center we specified a "box-in-box" sound isolation design. This design strategy addressed the need to abate noise and vibration from passing trains and also the need for effective sound isolation between rooms of the cultural center. After the completion of construction, we performed acoustical measuring and found that we achieved isolation levels above D-85 between the multipurpose hall and the music hall (separated horizontally by a single column span), among the three practice rooms and between each of the halls and each of the practice rooms.

During the planning stage of the project, the Yokohama government representatives who provided requirements to the project asked for the sound isolation design to isolate the halls from the sound of Japanese taiko drumming in the practice rooms. We explained that while our sound isolation design would surely implement a high level of sound isolation, it is extremely difficult to completely isolate the sound of Japanese taiko drumming from other rooms in a same building. The city representatives accepted this constraint.

drumming performance
Drumming performance

Tsurumi Sogo High School Taiko Drum Club
Tsurumi Sogo High School
Taiko Drum Club

After the completion of construction, the Yokohama government representatives wanted to test the effectiveness of the center's sound isolation by inviting student members of the Kanagawa Prefectural Tsurumi Sogo High School Taiko Drum Club to perform in each of the halls and the practice rooms. The participating club members included a large number of female students and when they gave powerful drumming performances that averaged 100dBA and had peaks of 115dBA, their strength and skill surprised the construction crew and city representatives who attended the test. Even during these loud sound volume tests, drumming in the practice rooms could hardly be heard in the multipurpose hall and the music hall.

<<Acoustical Room Design of the Multipurpose and Music Halls >>

In developing the project programming for the new cultural center and especially for its main, multipurpose hall, the Yokohama government representatives took into account this facility's place among Yokohama's overall plan to redevelop and improve the theatres and performance venues in each of its cities. The macro view of the Yokohama government competed with the wishes of Tsurumi City local residents, who wanted the new hall to be of the same scale as an existing public facility, Tsurumi-kaikan, which had a maximum seating capacity of 934 seats. The Salvia Hall multipurpose hall's compromise solution of 550 seats makes Salvia Hall the largest venue among municipally run theatres and halls in Yokohama's 18 cities, while being a smaller scale hall than the old Tsurumi Hall.

Multipurpose hall interior shown with stepped seating configuration
Multipurpose hall interior
shown with stepped seating configuration

flat-floor configuration
Flat-floor configuration

Seating in the music hall
Seating in the music hall

The meaning of the Chinese character "tsuru", the first character in Tsurumi City's name, inspired the gently curved, graceful lines of Salvia Hall's interior design. The character means "crane", the sleek and graceful bird often depicted in Japanese art.

The multipurpose hall's programming required a room acoustical design that achieves both superior acoustical performance for music concerts and enables the hall to be used for events that need a flat floor, such as business-style award ceremonies and gallery-style exhibitions. Because of this hall's diverse programming, we installed retractable banks of stepped seating that can be stored at the side of the hall when it is used for events that need a flat floor. During review of this design, the client expressed concern that retractable seating tends to lack sturdiness. To address this concern, we added plywood pieces to the seating banks to make them more rigid and we specified improvements to the design of the chairs to better approximate the sturdiness and quality of fixed seating.

The music hall, designed specifically for music performances, has a room acoustical design with walls, ceiling and seating all installed as fixed elements. The design creates a unified feeling between audience and stage. As soon as the cultural center began taking reservations to rent the venue, its calendar became completely booked for several months into the future. The music hall's 100-seat capacity will make this hall a very popular venue for concerts organized by local residents.

<<Salvia Hall's Opening, the Great Tohoku Earthquake and the Days Ahead >>

Salvia Hall's schedule of opening events for its March inauguration was cut short six days after the official opening by the Great Tohoku Earthquake. Days of planned electrical outages and limited train service followed in the Kanto Region that includes Tokyo and Yokohama. The crisis situation unavoidably led to concert and event cancellations and the disaster understandably cast a shadow on what would otherwise have been days of gala concerts and celebration.

As daily life in eastern Japan returns to normalcy, Tsurumi City residents will have the chance to become acquainted with their new cultural center. Salvia Hall will surely play an important role in the cultural life of this community.

<<Some Historical Facts about Tsurumi City >>

The history of Tsurumi City is mentioned in Yokohama's Japanese Web site. At the end of the Kamakura Era (1185-1333), annals record a meeting between the heads of two warring clans, Yoshisada Nitta and Takatoki Hojo, at the "battle of Tsurumi". Also, the Tsurumi place name can be found in the "Azuma Kagami" chronicles of the period. But there is no clear historical explanation for why the bird that inspired Salvia Hall's interior design and the "Sea Crane" complex's name is part of the city's name.

During the Meiji Period (1868-1912), Tsurumi City was a fishing village. In the following Taisho Era (1912-1926), Soichiro Asano, who later founded Asano Cement Company, began a landfill business in the area. As the Keihin Industrial Zone that stretches along the Japanese coast west of Tokyo grew to be one of Japan's four largest industrial zones, Tsurumi developed into a hub of employee housing units with shopping, movie theatres, restaurants and other amenities for the increasing number of local residents. Mr. Asano succeeded as an entrepreneur and expanded his businesses to become the Asano Zaibatsu. He established Asano Shipbuilding, which later merged with Nippon Kokan K.K. and, even later, became JFE Steel Corporation. The Tsurumi Train Line, built on land created by Mr. Asano's landfill enterprise, enabled the growth of the Keihin Industrial Zone where many related companies still have offices and plants. Also, a stop on the Tsurumi Train Line named Asano Station keeps alive the legacy of Mr. Asano's role in the city's development.

Salvia Hall has a Web site (in Japanese) with a schedule of upcoming events at the cultural center and information about how to rent the facilities.

Nagata Acoustics Chosen Acoustical Consultant for Harbin Concert Hall (China)

By Keiji Oguchi

China's Harbin City will build a new concert hall building featuring a 1,200-seat main hall for orchestral music and a 400-seat recital hall. At the end of 2010, the city held a competition to select the project's architect and awarded the project to the team of Arata Isozaki & Associates, Shanghai Xian Dai Architectural Design (Group) Co., Ltd and Nagata Acoustics.

<<Harbin City's European, Japanese and Classical Music Connections >>

Harbin City is located in the most northeastern part of China in Heilongjiang Province. The city is a major metropolitan center with a population of 10 million people. In the 19th century, the area experienced a large influx of people, especially Russians, who journeyed to Harbin on the newly constructed Trans-Siberian and Chinese Eastern railways. Even today, the shop-lined streets of the neighborhoods these immigrants built have an ambience that seems more European than Asian.

Harbin City's historical connection with Japan suffered an unhappy period in the years leading up to and during World War II, but the city also has a strong musical connection with Japan that dates back to the pre-war years. At that time, Harbin City supported a professional orchestra, the Harbin Symphony Orchestra and one of Japan's conductors, Maestro Takashi Asahina served as the orchestra's artistic director for two years. Also, after the Russian Revolution, some musicians who fled the Soviet Union went to Harbin and from Harbin to Japan where they contributed significantly to the flourishing of western classical music.

<<Harbin Concert Hall >>

The site dedicated to the new Harbin Concert Hall is located in the Qunli New Development Zone on the south bank of the Songhua River that flows along the north end of Harbin City. Qunli New Development Zone will be a cultural hub of the city, with museums and theatres as well as the new concert hall building.

The concert hall building's architectural design takes its inspiration from the motif of "ice crystals" and has the shape of an intriguing glass enclosure. One of the building's walls will also serve as a wall of the main hall for orchestral music. The use of a glass wall for a concert hall presents acoustical challenges for Nagata Acoustics to address in its sound isolation and room acoustics designs.

Currently, construction is about to begin on the underground level, most of which will be occupied by a parking garage. The design development stage for the above-ground floors is also in progress.

Bosch Communications Systems Product Introduction Days 2011, in Xiamen City, Fujian, China

By Makoto Ino

I recently attended the 2011 new products event for Asia and the Pacific hosted by Bosch Communications Systems Product Division at Xiamen Conference Center in Xiamen City, Fujian, China. I will begin this article with an overview of the history of the Bosch Group's entrance to the professional communications system and audio systems market and then discuss the company's current strategy and products in this industry.

<<Bosch Group History >>

The Bosch Group began as a manufacturer of the inventions of Robert Bosch in Stuttgart, Germany. Mr. Bosch invented the magneto ignition device and other spark plug and fuel injector devices and systems for automobiles. After opening the first factory in Stuttgart in 1901, the company rapidly expanded to become an international presence in the automotive industry. Today, the Bosch Group's Web site calls the company a "leading global supplier of technology and services … in the areas of automotive and industrial technology, consumer goods, and building technology".

In 2002, Bosch Group acquired the Dutch company Philips Communications Security Systems, a manufacturer of public address systems and closed circuit TV (CCTV) cameras. With this newly added expertise, Bosch established its Bosch Security Systems Division. In 2006, Bosch Group acquired the U.S. company Telex Communications, the manufacturer of Electro-Voice ("E.V.") and DYNACORD professional audio system products.

The current year marks the 125th anniversary of the founding of the first Bosch Group company. This year is also the 100th anniversary of the introduction of Bosch products in Japan and the 30th anniversary of the introduction of E.V. products in Japan.

<<Commercial Use Loudspeakers >>

Before the 1980s, fixed installation use loudspeaker systems typically separated the high frequency drivers and horns and the woofers into separate enclosures. In the 1980s and 1990s, high frequency and low frequency speaker units became combined into single enclosures. In addition, from the middle of the 1990s, vertically stacked line array speakers came on the market and experienced steady growth.

Despite the steady growth in adoption of line array loudspeakers, single enclosure speaker systems continue to have advantages. They can be procured with a wide range of output's power and directivity characteristics and they are available in a broad range of prices, giving the system designer the most freedom to determine a speaker's set of specifications. One box speakers are also superior to line array speakers in terms of ease of use. Major commercial speaker manufacturers with many years in the industry, such as E.V., JBL and EAW, offer strong product line-ups of these kinds of speakers.

Xiamen Conference Center Main Conference Hall
Xiamen Conference Center Main Conference Hall

<<Showcased E.V. Products and Audinate's Dante? Networking Technology >>

At the Bosch event, the new E.V. products primarily seemed to target the Chinese market. The models featured mostly simple, compact and relatively low cost designs.

Bosch also introduced products that incorporate Audinate's new digital audio networking technology, Dante. The event included a well-attended demonstration of sound reproduced using the Dante technology during which many of the attendees intently focused on a serious evaluation of this networking solution.

The event also included a tour of the Xiamen Conference Center with the opportunity to listen to its sound reinforcement system. The center has an analog mixing console, and I found the amplified sound to have adequate clarity and overall good sound quality with natural and pleasing character.

Nagata Acoustics Inc.

(Tokyo Office)
Hongo Segawa Bldg. 3F, 2-35-10 Hongo
Bunkyo-ku, Tokyo 113-0033, Japan
Tel: +81-3-5800-2671, Fax: +81-3-5800-2672

(LA Office)
2130 Sawtelle Blvd., Suite 308
Los Angeles, CA 90025, U.S.A.
Tel: +1-310-231-7878, Fax: +1-310-231-7816

(Paris Office)
75, avenue Parmentier
75011 Paris, France
Tel: +33 (0)1 40 21 44 25, Fax: +33 (0)1 40 21 24 00

E-mail: info@nagata.co.jp

[ Japanese Version ]