In 1781, architect Johan Carl Friedrich Dauthe constructed one of the earliest philharmonic concert halls by retrofitting an upper floor of a textile trading house in Leipzig, Germany. Famous for its acoustics, the rectangular shape of the Gewandhaus became a model for classical music venues in subsequent years. Though the field of architectural acoustics would not appear on the scene for another century, Dauthe had already hit on a magic formula: Rectangular rooms sound better.
According to new research from Aalto University in Finland, there’s a valid scientific reason why so many orchestra halls are shaped like shoe boxes, and why halls of that shape are among the best-ranked halls in the world by musicians and conductors. It’s because the human ear is on the side of the head. In a rectangular hall, where the audience and the orchestra face one another, the music flows out to each side and then bounces off the walls. This, in turn, directs the sound to the listeners’ ears from spots where human hearing is most sensitive. These reflections off the sidewalls enhance the perceived dynamic range of that sound.
The researchers went to 10 unoccupied European concert halls of different shapes and played a recording of an orchestra. Mannequin heads in the audience were equipped with microphones in the ears to measure the spectrum of sound that the music produced. The researchers found that the halls shaped like a shoebox hit a sweet spot with ears, enhancing the nuances we perceive in the music as the notes vary in volume. So it makes crescendos sound even more awesome. In a fan-shaped or vineyard-shaped hall, the sound isn’t reflected as directly from the side, and the effect isn’t as strong.
“When sound arrives from the sides of the head, the shape of the human head and ears emphasize the same frequencies produced by higher orchestral-playing dynamics,” Jukka Pätynen, the study’s lead author, tells Co.Design. So because of the shape of the ears, when the orchestra plays a section of the piece fortissimo (very loudly), the structure of the shoebox hall helps intensify the music by magnifying the differences the audience hears between the loudest and softest notes. “In other words, fortissimo is ‘more’ fortissimo in halls with high dynamic responsiveness,” according to Pätynen.
This is a compelling argument for not getting too fancy with the architecture of concert hall interiors. The long, flat shoebox shape may not be the best for viewing classical music, and it may even look a little bland in the modern era. But the sound is superb.