Quietness, Comfortable Sound and Excellent Acoustics NAGATA ACOUSTICS

News 13-03 (No.303)

Issued : March 25, 2013

[ Japanese Version ]

Stanford University Bing Concert Hall Opens

By Motoo Komoda

Stanford University needs no introduction. This school, with its campus less than an hour's drive south of San Francisco, California on the U.S west coast, numbers among the world's most prestigious institutions of higher learning across many science, engineering, medical and humanities disciplines. Situated in the heart of Silicon Valley, Stanford alumni have founded some of the world's most successful high tech firms, including Google and Yahoo! among others. In 2005, Apple's Steve Jobs gave the commencement address at Stanford's graduation ceremony. I could continue this list of accolades for many more sentences and there would still be many praiseworthy facts about Stanford to mention.

<< The Performing Arts at Stanford and the University's Music Department >>

Building Exterior
Building Exterior
View of the Hall Interior
View of the Hall Interior

Stanford Live is the university organization charged with nurturing and supporting the arts, artists and arts performances on the Stanford campus. This includes not only study and performances by faculty and students, but also obtaining the cooperation of off-campus arts institutions, organizations and professionals to produce performing arts events and mentor the university's budding performing artists. Formerly known as Stanford Lively Arts, Stanford Live has more than 40 years of accomplishments that include a varied and full performing arts calendar, visiting artists in residence, involvement by faculty and students, commissions, premieres and other performing arts endeavors.

Stanford's music department spans the genres of classical music, jazz and contemporary music, as well as offering multidisciplinary studies across technology, music and acoustics. Student options for participating in music performing groups include, among others, Stanford Symphony Orchestra, Stanford Philharmonia Orchestra and "New Ensemble" dedicated to performing new music. As many as 150 concerts have been performed annually at Stanford recital halls and at its Memorial Church. The opening of the new Bing Concert Hall at long last provides Stanford University with its one true concert hall.

<< Designing the Bing Concert Hall for Full Orchestra Performances >>

Plan of the Hall
Plan of the Hall
Section of the Hall
Section of the Hall

The Bing Concert Hall project total cost was $112 million. The hall building interior has 10,000 sq. m. (112,365 sq. ft) of space. In addition to the concert hall, the building houses a rehearsal room, dressing rooms and offices. The hall's namesakes, Helen and Peter Bing, donated a very generous sum to the project. Ennead Architects (formerly Polshek Partnership) created the architectural design for the project. Nagata Acoustics served as the acoustical consultant for the acoustical room design and the sound isolation and noise mitigation designs.

Bing Concert Hall has 842 seats. From the seat-count perspective, the hall belongs to the class of small or medium-size concert halls. This size hall typically aims to be a venue for chamber music ensembles and smaller performing groups. However, on this project, our client required that Stanford Bing Hall have a design suited to full orchestra performances.

This client requirement posed a significant acoustical design challenge that Nagata Acoustics solved by specifying a generously wide dimension for the hall's stage and a tall height dimension for the hall's ceiling. As a result, we achieved a spatial volume of 17,000 m³ (600,000 cu. ft). To understand how spacious the Bing Hall is, we can compare it to the 1,680-seat Vienna Musikverein where the spatial volume is 15,000 m³ (530,000 cu. ft). Bing Hall has half the number of seats of the Vienna Musikverein, but an even more expansive spatial volume than that illustrious hall.

<< The Hall's Room Acoustical Design >>

Sound Diffusing Wall(by courtesy of Jeff Goldberg)
Sound Diffusing Wall
(by courtesy of Jeff Goldberg)

Frequency Response of the Reverberation Time
Frequency Response of the Reverberation Time

In Bing Hall, the audience seating surrounds the stage in blocks of seats that form an arena-style configuration. The hall's interior acoustical design creates a strong feeling of intimacy between the audience and the performers. A key factor in achieving this characteristic is the height of the stage floor, which is at the same level as the first front row of audience seats. Technically speaking, compared with most other halls, Bing Hall has a stage height of "zero". The zero height of the stage floor means that the stage floor is lower than any other element of the hall interior. This stage floor positioning plays a significant role in creating both the strong feeling of intimacy and, also, the excellent musical presence the hall has.

Bing Hall has an elliptical footprint. In oval halls, undesirable focusing phenomena occur more easily than in rectangular halls. To ensure the prevention of focusing in Bing Hall we installed three-dimensional wall treatments on the walls behind the last rows of audience seating. During the design phase we built a 1/24 scale model of the hall and used it to extensively and comprehensively test our design and confirm that the hall would be echo-free. In addition to the three-dimensional wall treatments behind the audience seating, we designed the partial walls at the fronts of audience blocks and most of the ceiling to have textured, wave-like surfaces. This design element promotes sound diffusion of higher frequency sounds.

Bing Hall's sound reverberation time measures 2.4 seconds (at 500 Hz and calculated for a full hall based on measurement with the hall empty). This is a rather long reverberation time for a hall of this size and the hall has truly rich acoustics. By listening to orchestral, chamber music and solo rehearsals and concerts already performed in the hall, I also confirmed that the hall achieves excellent sound clarity.

<< Inaugural Season Concerts >>

On January 10, 2013, Stanford officially took the keys to the new Stanford Bing Hall building. The very next day, on January 11th, the St. Lawrence String Quartet and the San Francisco Symphony conducted by Maestro Michael Tilson Thomas performed the extraordinary opening night concert. In the days and weeks that followed, pianist Emanuel Ax, cellist Yo-Yo Ma and violinist Midori each took the stage to rave reviews.

Stanford University as well as Mr. and Mrs. Bing expressed their joy at the successful completion of the hall. Nagata Acoustics is delighted to have participated in this project and designed acoustics so pleasing to our clients and the hall's audiences.

For more information about Stanford Bing Hall, visit the Stanford Live website.

On Eve of Renovation, Hirosaki Community Center Celebrates Pre-50th Anniversary

By Chiaki Ishiwata

The original community center hall stage seen from the audience seating
The original community center hall stage
seen from the audience seating

For some of our readers Kunio Maekawa is best known as the architect who designed Tokyo Bunka Kaikan. More than 50 years after its opening, Tokyo Bunka Kaikan continues to be loved by Japanese and international musicians and patrons. In Japan's northern Hirosaki City, in Aomori Prefecture, another Maekawa-designed hall also continues its long-lived popularity. This hall, in the Hirosaki Community Center, first opened in 1964 and is now in the midst of its first major renovation.

<< The Original Hirosaki Community Center >>

Hirosaki Community Center is located in Hirosaki Park, the site of the historic tower remnant of Hirosaki Castle. Adjacent to the community center stands a museum that Mr. Maekawa also designed. The community center's design features extensive use of exposed concrete and a stark bulky style sometimes described as brutalist. Yet the interior foyer exudes a memorably warm atmosphere lit by overhead lights made from copper piping.

The Hirosaki Community Center Hall seats an audience of 1,300 in a simple, single-floor, shoe-box configuration with wood-paneled walls. University of Tokyo Institute of Industrial Science Professor Emeritus Kiyoteru Ishii served as the acoustical consultant for the hall. To promote sound diffusion, indentations and protrusions were installed artfully in the side walls of the audience seating area.

<< Architect Maekawa's Ties to Hirosaki City >>

Architect Kunio Maekawa had a deep professional connection with Hirosaki City. When he returned to Japan after working in Paris with Le Corbusier, Mr. Maekawa designed his first work of architecture in Hirosaki City, the Kimura Manufactural Research Institute. In the years following, he designed other buildings in the city, for a total of eight structures, including the Hirosaki municipal crematorium hall that he created toward the end of his life.

The city and its residents take pride in this heritage of Maekawa architecture. The "Association for treasuring the Kunio Maekawa buildings" has been running by Hirosaki citizen volunteer, and also at the main train station's tourist information office, the city distributes a pamphlet about Mr. Maekawa's architectural accomplishments.

<< Bidding a Temporary Goodbye to the Community Center >>

Flyer for the Pre-50th Anniversary Celebration
Flyer for the Pre-50th Anniversary Celebration

Visitors listen to a description of the hall
Visitors listen to a description of the hall

The Hirosaki Community Center is now undergoing a major renovation that includes an overhaul of the stage equipment and functionality, as well as replacement of the audience seating with new, wider seats, among other changes. In January, 2013, with the start of construction imminent and the timing just one year before the building's 50th anniversary, the community center organized an event they called a "Pre-Anniversary Celebration". About 150 people attended the event, which included a guided tour of the hall with explanations by Mr. Yoshikazu Nakamura, formerly of Mayekawa Kunio Associates, Architects & Engineers. The pre-anniversary event also included a quena and accordion duet performance and other mini concerts.

During the event, participants enjoyed access to parts of the hall that patrons usually only see from the distance of their audience seats. Participants walked on the stage and could look into the trap area below stage. The guided tour included a demonstration of the manually operated original stage reflection panel apparatus. A new, electrically operated system will be installed as part of the renovations now in progress.

As the event's attendees walked through the foyer and lobby and, of course, while they spent time in the hall, musicians performed mini concerts. It was a chance to enjoy and reconnect with the acoustics of each of these spaces.

Nagata Acoustics is pleased to have the cooperation of Mayekawa Associates, Architects & Engineers as we prepare and implement the acoustical design for the hall's renovations. I look forward to reporting on this renovation project again after its completion.

Towards A Correct Understanding of "Low Frequency Noise"

By Ayako Hakozaki

From time to time for more than a decade, the Japanese media have put a spotlight on concerns about "low frequency noise". As a result, most people know the term "low frequency noise". But how many people really know what low frequency noise is?

Last autumn, the Acoustical Materials Association of Japan held a technical seminar on the theme of "Sounds that Cause Problems in Residential Housing". At the seminar, Mr. Hiroaki Ochiai of Kobayasi Institute of Physical Research spoke on the topic of "Low Frequency Noise Problems in Residential Housing". According to Mr. Ochiai, among noise complaints filed by Japanese home owners and residents in various locales, as many as 40% of the complaints that cited low frequency noise as their cause turned out to be problems caused by something other than low frequency noise.

With Mr. Ochiai's talk still fresh in my mind, I will devote this article to defining what low frequency noise is, discussing the effects it has and identifying the real causes of many low frequency noise complaints.

<< A Definition of Low Frequency Noise >>

Range of Sound Frequencies the Human Can Hear or Feel
Range of Sound Frequencies the Human Can Hear or Feel

The human ear can generally hear sounds that have frequencies between 20 Hz and 20,000 Hz (known as the audible range). With this fact as the starting point, how high can a frequency be and still be considered a low frequency sound?

Different countries set the bar at different frequencies. For Japan, the Ministry of the Environment prepared a publication on low frequency noise that includes the proposed definition of sounds between 1 Hz and 100Hz. Using this definition, low frequency noise includes sounds below the human audible range. These sounds are known as "infrasound".

When audiophiles hear sounds of up to 200 Hz, they may think of these sounds as being low frequencies. However, the definition of "low frequency sounds" has an upper limit considerably lower than the sounds audiophiles may refer to as "low frequency sounds".

<< What Are the Effects of Low Frequency Noise? >>

The possible effects of low frequency noise can be categorized into two types. One type is the effects on our bodies and minds and the second type is physical effects on objects in our surrounding environment. Examples of the former include negative impacts on our mental state, such as insomnia and irritability, and physiological effects, such as headaches, ringing in the ear and a feeling of heavy pressure, especially around the ears. The most common examples of physical effects on the surrounding environment are vibrating or rattling windows and doors.

As shown on the accompanying graph, even for frequencies below those audible to the human ear, when the sound pressure level increases, the physiological effects such as a feeling of heavy pressure and the environmental effects such as rattling windows and doors can be detected by human beings. When the low frequency sound is within the audible range, human beings can also hear the sound. It's worth noting that for frequencies below the sensory threshold (for the audible range, this is the smallest audible value), researchers have concluded that low frequency noise does not have an effect on the mental and physiological well-being of humans.

<< The Sources of Low Frequency Noise Complaints >>

The most frequent sources of low frequency noise complaints are noise from large machinery and equipment such as the machinery in factory plants, metal fabrication machines and large rooftop HVAC equipment. In recent years, noise from wind turbines has also become a topic of discussion, but sound generated by some wind turbines is characterized by distinctive frequencies that are a bit too high to be characterized as low frequency noise. As for claims that low frequency noise causes a constant sound throughout the day and night, it is not unusual for the cause of this problem to be tinnitus rather than sound from an environmental source.

The Japan Ministry of the Environment's website provides links to the ministry's report on this topic, as well as guidelines about how to deal with low frequency noise claims and specific real-life examples.

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 ]