What is the optimal shape of a concert hall?
Building a concert hall is a mixture of science, engineering, art, and politics. Politics is important because the people who provide the funds have goals for the use of the hall. Consider, for example, the history of Philharmonic Hall in Lincoln Center, New York City. It was originally designed to be similar to the Boston Symphony Hall—long and narrow. But, a campaign led by one of the major newspapers in the city argued that the hall should seat more than 2,400 people, and so the architects made the hall wider. But when it was completed in 1962 critics were very unhappy with the sound. The wider hall did not have enough initial reflections and sounded dry. It was equipped with “clouds,” reflectors hung from the ceiling, but reflections from them were too delayed to be effective. Another problem was that performers on the stage couldn’t hear each other.
In 1973 Mr. Avery Fischer contributed over $10 million to support a complete reconstruction of the hall, and the hall is now named after him. The changes improved the acoustics, but the large stage reduced the loudness of bass sounds and the initial reflections were still too strong. Curved surfaces on the stage made of extremely tight-grain maple wood have improved bass problem, and reflectors consisting of 30,000 dowel rods were installed on the side walls.
Except for classical music concerts and opera, most performances use electronic amplification. Loud speakers can be located throughout the hall, and their response to different frequencies can be adjusted to compensate for shortcomings in the hall. The signal to speakers far from the stage can be delayed so sound from all speakers arrives at the same time. Further, these changes can be adjusted so that the hall has the best acoustics for any type of use.