Tetsu Kobayashi

Sound and vibration control for the Tokyo International Forum

The acousticians for the Tokyo International Forum were faced with a number of very severe noise and vibration problems related to the siting of the complex in the center of downtown Tokyo, the placement of the performance halls next to one another, and the location of a portion of the mechanical equipment on the roof. In addition, subway lines ran parallel to three of the boundaries of the structure, another line ran under the building, and the main tracks of Japan Rail ran above ground alongside the major atrium. This paper will discuss the noise criteria set for the performance rooms and other noise sensitive spaces, the noise and vibration measurements taken to determine the severity of the train‐related conditions, predictions of other noise and vibration sources, and the solutions developed by the design team to meet the criteria required by the program. Among the solutions are a secant wall surrounding the foundation, box in box construction for the four performance halls, blocking mass installatio...

Room acoustic designs for the Tokyo International Forum

The room acoustic design of the Tokyo International Forum centered around the four performance halls: the convention center, the atrium, and the large multi‐use meeting/dining halls. This paper will describe the program use of each space and the acoustic criteria developed to meet these requirements. Major emphasis will be placed on Hall A, a 5000‐seat congress hall that was to be used to unamplified symphonic concerts and operas as well as highly amplified Broadway musicals and rock concerts, and Hall B, a 1500‐seat classical music hall and piccolo opera house that also would be used for conferences and popular entertainment. A unique architectural feature of Hall B is the first design and installation of a Concert Hall Shaper, a device that enables a proscenium theatre with a stagehouse to be converted to a single acoustic volume for events such as symphony concerts requiring a longer reverberation time. Hall C, an extremely flexible space for fashion shows, summit meetings, and large receptions, and Ha...