Quietness, Comfortable Sound and Excellent Acoustics NAGATA ACOUSTICS

News 10-04 (No.268)

Issued : April 25, 2010

[ Japanese Version ]

Kyoto Municipal Kyoto Horikawa Senior High School of MUSIC Building Completed

by Akira Ono

Kyoto City Public Music High School exterior
Kyoto City Public Music High School exterior

Kyoto Municipal Horikawa Senior High School Music Department began instruction in 1948 as the first department for music training in a Japanese public high school. Japan was still in a state of post-war chaos and, at a time when people barely had enough to eat and little more than ragged clothes to wear, the local Kyoto population surely expended uncommon effort, fortitude and determination to establish a new department and music curriculum in a public secondary school. A history of the school recounts that a private donation of five pianos became the inspiration that led the residents of this part of Japan's famous ancient city to found the Horikawa Senior High School Music Department.

The Horikawa Senior High School Music Department, or "Hori-On" as it is affectionately abbreviated (using the first syllables of the school's location and of "ongaku", the Japanese word for music), rapidly developed a tradition and reputation as an institution where teachers with a strong drive and rigor for excellence teach, and where students dedicated to their love of music compete fiercely to earn admission. Hori-On counts among its alumni many top-ranking musicians across a wide range of genres and a variety of music scenes, including percussionist, keyboardist and composer Stomu Yamash'ta, conductors Kazuhiro Koizumi and Yutaka Sado, and violinist Taro Hakase.

<< Hori-On's Renaissance as a Magnet High School for Music >>

Concert hall interior (stage)
Concert hall interior (stage)

Concert hall interior (audience seating)
Concert hall interior (audience seating)

In 1998, the 50th year after the founding of the Horikawa Senior High School Music Department, the department and Kyoto City acknowledged this milestone year by separating the department from Horikawa Senior High School and establishing the department as the core of a magnet music high school named Kyoto Municipal Music Senior High School. It is Japan's only magnet high school for music training.

In addition, Kyoto City decided to build a new campus for the re-established and re-named Kyoto City Public Music High School, using a site southeast of Nijo Castle at the intersection of Horikawa and Oike avenues formerly occupied by Joson Junior High School. In March, 2010, the new campus and building of Kyoto Horikawa Senior High School of MUSIC ("ongaku") completed, just in time for the April start of the new Japanese school year. The building's completion and the school's reopening brings back to life the Hori-On name beloved by alumni and neighborhood residents alike.

On March 26, the school held a ceremony to celebrate the completion of construction. The ceremony's many attendees included people associated with the project and the school, as well as local dignitaries. The Kyoto Metropolitan Area government proactively supports participation by self-administering neighborhoods in the planning and development of public schools, and local neighborhood officials and administrators played a vital role in this project. Naturally, many of them came to celebrate the school's completion.

The Joson neighborhood administration lobbied to have the school built in its community and organized a music festival to highlight the community's interest in music. Apparently, in ancient times, when directions were associated with the Chinese zodiac, the Joson section of Kyoto was said to be located "between the dragon and the snake" directions (southeast) from Nijo Castle. Whether aptly or coincidentally, the dragon is a Chinese zodiac symbol considered to have great creativity and people born in the year of the snake are expected to love music.

Attendees at the construction completion ceremony heard a video message sent by alumni Yutaka Sado. In his remarks, Maestro Sado exhorted the school and today's students to not become conceited in the fine new school facility, but to instead strive for true achievements. The maestro's words brought to mind the reputation and spirit of his alma mater since its founding.

<< Project Overview >>

Kyoto City selected the project participants for the new music high school building using the Private Finance Initiative (PFI) method. Rui Sekkeishitsu Group served as the architect and general manager, a joint venture of Yoshimura Construction Co., Ltd. and Mirano Co., Ltd. served as the general contractor and Orix Facilities will be responsible for ongoing building maintenance and management.

The high school building's interior includes a concert hall with seating for an audience of 300 persons, classrooms, music lesson rooms, large and small practice rooms and a gymnasium (named "Joson Arena"). The design of Joson Arena took into consideration the expectation that it will be used as a practice space by the school's brass band and for performances, in addition to being used for athletics.

In addition to the high school, a separate structure on the campus houses the Kyoto City University of the Arts Horikawa Oike Gallery. The gallery will exhibit both student works and works from the university's collections, which contain notable pieces from the younger years of a number of famous artists.

<< Sound Isolation Planning for the High School Building >>

The new Kyoto City Public Music High School is very near the northeast corner of two major Kyoto thoroughfares, Oike-dori and Horikawa-dori avenues. Immediately to the east of this intersection, Oike-dori Avenue angles rather sharply to the south and the Tozai Subway Line that runs below Oike-dori Avenue also makes a curve, at a location almost directly below the new high school's campus. When we researched the site conditions during this project's planning phase, we recognized that the subway would generate noise and vibration and that the noise and vibration would be exacerbated by the curve in the train tracks, so we decided to implement an anti-vibration and sound isolation strategy for the school's concert hall. This strategy was also necessitated by the need to provide sound isolation between the hall and the school's music lesson and practice rooms. As a result of the implemented anti-vibration and sound isolation strategy, there is absolutely no transference of subway noise or vibration to the hall space.

<< Design of the Concert Hall's Room Acoustics >>

Stage sidewall panels for adjust the sound absorption
Stage sidewall panels
for adjust the sound absorption

The high school's concert hall will be used for a variety of music performance activities that include student concerts open to the public, student instruction and exams, and recitals and performances for student audiences. The school will also use the space as the school auditorium for ceremonies and lectures. In addition, the school plans to make the concert hall available to the general public as a rental space. In summary, the programming for this hall covers a very broad scope of activities.

In the design of the concert hall's room acoustics, we made achieving fine concert hall acoustics our primary objective. The high school's overall building height and its hip roof exterior architectural design created an overall constraint on the concert hall's shape. Within this constraint, we aimed to obtain the highest possible ceiling height and spatial room volume. We also set the goal of a hall with a sense of both intimacy and envelopment and, to achieve the sidewall and rear wall sound reflections that contribute to these characteristics, we designed a protrusion midway along the side and rear walls that promotes and directs the sound reflections away from below the protrusion and the sidewalls. In addition, to the extent possible without creating echoes, we made the rear wall of the hall a sound-reflecting surface.

Conversely, to ensure a high level of speech clarity when the school uses the hall for ceremonies and lectures, we installed a manually operated, sound-absorbing curtain that can be set to cover the entire rear wall of the stage. Additionally, at the sidewalls of the stage we installed panels that can be opened or closed to adjust the sound absorption characteristic of the stage sidewalls. Rotating the panels to their open position reveals the sound-absorbing surfaces on the rear sides of the panels. This configuration both controls sound reflections from the stage sidewalls and reduces sound reverberations.

When the hall is fully-occupied, the sound reverberation time measures 1.8 seconds and, with the stage rear curtain set and the stage sidewall panels opened, the sound reverberation time measures 1.5 seconds (both measurements at 500 Hz). For a hall of this size, these are rather long reverberation times. I listened to the hall with the sound-absorbing measures of the stage rear curtain and stage sidewall panels in place and confirmed that they will effectively balance the hall's acoustics for clarity of speech during speaking events.

A music school's concert hall will naturally be used on a daily basis by students who play a large variety of musical instruments and designing a hall appropriate to the acoustical needs of such a wide range of instruments is a difficult challenge. At Kyoto City Public Music High School, the school and students will be able to use the stage's adjustable, sound-absorbing rear and sidewall elements to customize the hall's acoustics and achieve the appropriate acoustical environment for the variety of musical instruments the students play. As they find the best acoustics for each kind of performance, I think they will quickly become fond of this new venue's acoustics.

Kyoto City Public Music High School's Web Site.

"Alios Annex" - "Bonus" Facilities at Iwaki Performing Arts Center "Alios"

by Ayako Hakozaki

We previously introduced Iwaki Performing Arts Center "Alios" to this newsletter's readers in our May, 2008, June, 2008 and August, 2009 newsletters. In May, 2010, Alios (located in Iwaki City, Fukushima Pref.) will celebrate the first anniversary of its grand opening. Until now, we naturally shined the spotlight on the large hall, mid-size theatre and small theatre in Alios' newly constructed main wing. In addition to this new building, the project's Private Finance Initiative (PFI) funding also included the remodeling and related construction and construction management of the existing Iwaki City Ongakukan and Iwaki Cultural Center Hall.

The Iwaki City Ongakukan project, awarded to Iwaki-based contractor Kajiwa Corporation, remodeled the old music hall building, which has been renamed "Alios Annex". The project began as the first phase of the Alios main wing project and completed at the same time with other buildings that the main wing completed (two years ago). The Iwaki Cultural Center Hall remodel project completed in March 2010, and a May opening is planned for the renovated cultural center building. In this article, I will introduce readers to Alios Annex and its predecessor, Iwaki City Ongakukan, and I will share some utilization statistics about the annex.

<< Iwaki City Ongakukan and the Scope of Its Remodel Project >>

The old Iwaki Music Hall large rehearsal room with two-story high ceiling
The old Iwaki Music Hall large rehearsal room
with two-story high ceiling

Iwaki City Ongakukan was built in 1988 as a facility for music practice by the city's residents. Many Iwaki City residents participate in wind instrument ensembles such as brass bands and other music ensembles. For close to two decades, the city's local musicians as well as middle and high school students used Iwaki City Ongakukan as the venue for their practice sessions and concerts. While the old building's primary purpose was to be a rehearsal and practice venue, its largest rehearsal room had a two-story high ceiling and often served as a concert and recital hall. In addition to this room, Iwaki City Ongakukan had another large rehearsal room, two mid-size rehearsal rooms and seven small rehearsal rooms for a total of eleven separate rooms. The old building's design for most of these rooms included the sound isolation measures of glass wool floating foundations and anti-vibration interiors.

The remodel project concentrated on the two large rehearsal rooms. We redesigned the room with the two-story ceiling to be a small concert hall exclusively for music performances (discussed in detail later in this article). The other large rehearsal room also underwent complete transformation to become a multipurpose practice and rehearsal studio appropriate both for music practice and for ballet, other dance genres and drama practice. To accommodate these uses, we gave special attention to preventing the impacts by dancers and others on the floor of the studio from transferring to the rooms below. The isolation strategy we implemented uses a rubberized anti-vibration floor system for this room. In addition, we installed sound isolating room dividers that enable this room to be used either as one large room or, simultaneously, as two smaller rooms. When the room dividers are stored away, the large room measures a spacious 200 sq. m. (2,153 sq. ft). As for the building's mid-size and small practice rooms, we implemented various interior changes and enhancements depending on the room and its location in the building layout, and we replaced the doors of the rooms with soundproof-rated doors.

<< Remodel from Large Rehearsal Room to Small Concert Hall >>

The new small concert hall (stage). After completion of the remodel project
The new small concert hall (stage).
After completion of the remodel project

The new small concert hall (audience seating). After completion of the remodel project
The new small concert hall (audience seating).
After completion of the remodel project

To transform the two-story ceiling, large rehearsal room into a small concert hall, we began by gutting the interior, leaving only the original building framing, which has room dimensions of 13.5 m. (44 ft) width x 21 m. (69 ft) depth x 8.6 m. (28 ft) height. In this space, we built the small concert hall with movable seating for an audience of up to 200 persons. While the hall is small in size, we nevertheless determined the need for a high level of sound isolation between the hall and nearby rooms. To do this, we rebuilt the room's anti-vibration and sound isolation structure. In addition, to enhance the concert hall functionality of the room, we added a backstage green room and corridor behind the stage, facilities that the old building's rehearsal room did not have.

In the hall's interior, because of its small size we focused attention on obtaining optimal sound diffusion. We designed walls with a gently curved shape, installed random ribbing to add protruding and recessed variations to the wall surfaces and we additionally created sound-absorbing surfaces in-between the large, curved sections of wall panels. Within the existing height restriction of the ceiling, we installed various equipments while achieving the maximum possible interior ceiling height by designing a sound-isolating upper structure of gently-sloped peaks below which we created six curved, visible ceiling sections. The mix of gently curved surfaces and the red upholstery of the movable seating combine to give the hall an atmosphere of richly colorful elegance and comfortable informality.

<< Alios Annex Utilization Trends >>

Alios Annex was already a very popular venue with the city's residents when it was still Iwaki City Ongakukan, and I was told that the remodeled building enjoys even greater popularity. I talked about the building's utilization with Mr. Konno, who has come on board as an Alios chief manager in connection with the Alios PFI.

In 2009, the small concert hall had a utilization rate of 66%, with some months having rates exceeding 80%. The mid-size and small music practice rooms had utilization rates between 60% and 80% in 2006. In 2009, these rooms reached utilization rates between 85% and 100%. In particular, the small practice rooms (30 sq. m. (323 sq. ft)) have a pretty consistent utilization rate of 100%.

According to Mr. Konno, "The opening of the Alios main wing seems to have inspired especially senior citizens to make use of the facilities and this demographic has helped push up the utilization rate of the annex."

Because the multipurpose practice studio no longer caters solely to musicians, it is apparently taking some time to establish its use for dance and theatre genres and its utilization rate has been a bit on the low side. Nevertheless, overall in 2009, Alios Annex had between 70% and 80% utilization for almost all of its rooms. Even after the remodeling of the building, the room rental rate for each of the rooms remains enviably low. For example, the 30 sq. m. (323 sq. ft) room can be rented for three hours for just a few hundred yen (equipment fees, such as a piano, excluded), or about the same cost as a tall Starbucks coffee. The low rental costs provide one reason for the high utilization rate.

Says Mr. Konno, "Two years after the opening of the Alios main wing, we now see many Iwaki residents coming to the main wing regardless of whether there is a performance scheduled or not. Many of these people use the rooms at Alios Annex and spend time before or after in the Alios main wing for as long as they wish to stay."

Iwaki Performing Arts Center Alios has become more than a venue for audiences to hear and watch performances. It is the true center of the city's artistic life and a gathering place for the community. Also, the economical Alios Annex clearly plays a significant role in making both the main wing and the annex popular destinations for the residents of Iwaki City.

Alios's Web Site.

Taichung Metropolitan Opera House Complex Begins Construction

by Toshiko Fukuchi

In 2005, Toyo Ito & Associates won the international design competition for the Taichung Metropolitan Opera House. On December 3, 2009, the project held its ground-breaking ceremony and began construction. As we mentioned in our January, 2009 newsletter, earthwork construction began more than a year ago. Thereafter, in 2009, the local Taichung construction company, Lee Ming Construction joined the project, enabling construction to proceed. The scheduled project completion date is in the winter of 2013.

The new opera house will be located in the central part of Taichung City, on a site surrounded by high-rise condominiums. The complex will include the 2,000-seat Grand Theatre Opera House, an 800-seat Playhouse for drama performances and a 200-seat space for experimental theatre. For the Grand Theatre, we have been performing useful testing in the 1/10 acoustical model.

I look forward to being involved in this project as construction progresses and the building takes shape.

Artist's conceptual view of the opera house exterior
Artist's conceptual view of the opera house exterior
Artist's rendering of the Grand Theatre
Artist's rendering of the Grand Theatre
"The Taichung Metropolitan Opera House is built by the Taichung City Government, Republic of China (Taiwan)."

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 307A
Los Angeles, CA 90025, U.S.A.
Tel: +1-310-231-7818, 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 ]