Garrett G Jones on sound mirrors at the Designing for Human Behavior blog at the University of Texas at Austin School of Architecture:
…. Microphones placed at foci the of the reflectors enabled a listener to detect the sound of aircrafts several kilometers out in the English Channel. My idea takes this primitive device and relocates it within modern contexts. Sound mirrors or sound theatres can be used at a more urban or residential scale as installations for people to sit and interact within. The premise is to sit within the concrete dome, which could be oriented in any direction, and that sounds of the surroundings become amplified as they are reflected and echoed within the dome.