In the late 80s I worked in a low cluster of buildings, each of which was topped with a band of vertical ridges spaced about 4" apart (sort of like a corrugated roof, but with vertical corrugations). One day a thunderstorm came through, and we discovered that the pulses of thunder, when they hit the corrugations, reflected as a quickly falling tone. The corrugations were working as an acoustic diffraction grating, with different frequencies reflecting in different directions.