Theory 98/Urban & Built Environment/Urban noise
Street Noise Is a Canyon Ratio
The claim
Noise propagation along a street canyon is set by the ratio of building height to street width, so a narrow canyon can amplify sound at height.
01Mechanism
Reflections from the façades trap sound and channel it upward; the aspect ratio determines how many reflections occur before escape.
02Prediction
Levels should track the canyon ratio.
03Refutation
Levels tracking traffic volume would remove geometry.