Matt Gilbert

An Acoustic Study of an Arched Bridge

There's a bridge in Greenville, SC that has some peculiar acoustic properties. If you walk under it, its arched ceiling can sustain echoes for very long times and these echoes change depending on where the listener is and where a sound is made in the space. It often goes unnoticed, but it's astounding.

I wanted to understand these echoes better, so I developed a program that would model the way sound travels through a space and bounces off of the walls. In the image above, starting from the top left and going down each column, it starts with a circle of sound expanding from its source. If a sound starts at the location, it gets sent back and forth across the archway, creating the echoes.

These images were created with a program developed in Processing. This project is part of a larger goal of finding elegant ways to visualize the acoustics of different spaces, so that they may be better understood and more confidently worked with as a medium for installations or architecture. Reflection Patterns was another approach to this issue.

As a sidenote, the design of my logo came out of earlier studies like this.

Update: The acoustics in this bridge have since disappeared, sadly. Some construction work somehow disrupted them. I know for a fact that the people working on it where not insensitive to the echoes, they just turned out to be very fragile.