The Tower of Voices is a monumental 93-foot-tall musical instrument that marks the gateway to and from an expansive living memorial landscape. Its forty chimes represent the voices of the forty passengers and crew members who took a vote to come together and fight terrorism on the morning of September 11, 2001. The chimes serve as a living tribute to these men and women, many of whose last messages to loved ones were telephone calls and recorded voice messages. Unlike any other wind chime tower in the world, it contains aluminum tubular chimes that create music when the wind blows through the concrete tower, which is ninety-three feet tall and fifteen feet in diameter, and the chimes are activated solely by the wind. Conifer and deciduous plantings are arranged in concentric rings to represent sound waves emanating from the tower. The chime notes span two octaves and include C, D, E, F sharp, G, and B, based on a C Lydian mode. Some chimes are tuned to nearly the same frequency to create subtle periodic variation in pitch and volume, and their lengths range from five feet to ten feet, with shorter chimes producing higher pitches and longer chimes producing lower pitches. The powder-coated aluminum chimes are eight inches in diameter with half-inch-thick walls, and five chimes hang from each of the eight tower columns. Their musical tones create both harmony and dissonance with the surrounding chimes, representing the voices of the passengers and crew members who gave their lives and through that action saved others that morning.
