Sound transmission experiments from an impulsive source near rigid wedges

Experimental sound transmissions in air from a spark source to a small microphone were made near rigid wedges. Two types of experiments were made. The first experiments were transmissions within an approximately 12° wedge and a 52° wedge. The Biot–Tolstoy exact wedge solution [I. Tolstoy and C. S. Clay, Ocean Acoustics (American Institute of Physics, New York, 1987), 2nd ed.] was used to calculate the theoretical impulse responses. Within the 12° and 52° wedge, the solution gives a finite set of images and a diffraction arrival. Theory and experiments matched. The second type of experiments measured the image or ‘‘optical’’ reflection as the reflection point was moved to the edge of a half‐plane and tested a Fresnel–Kirchhoff solution. The exact wedge solution gives a relative reflection amplitude of 1 compared to the reflection from an infinite plane. The Fresnel–Kirchoff solution of Trorey [A. W. Trorey, Geophysics 35, 762–784 (1970)] gives a relative signal of 1/2. Experiments were made near vertical incidence over a 270° wedge. They confirmed the correctness of the exact wedge solution and the incorrectness of the Trorey solution.