An extended study of diffraction of acoustic waves in the audible range is currently under progress in the anechoic chamber at Temple University. A probe microphone has been constructed by coupling to a12‐in.Bruel and Kjaer (B&K) capacitor microphone a rigid steel tube with a precision‐drilled 1‐mm‐diam hole. The output is fed into a B&K audio‐frequency spectrum analyzer and recorder. Since the measuring apparatus is so important in experimental studies in diffraction, extensive tests have been run to check the free‐field characteristics of the chamber and the frequency and directional response of the probe microphone. As a test of the precision of the apparatus, the diffraction patterns for rigid cylinders and spheres have been analyzed for various values ofka(ratio of circumference to wavelength) from 0.2 to 10. To obtain continuous readings, the microphone has been mounted to rotate at 2 rpm. The results have followed theory predictions in every respect, and the details of the “bright spot” and the numerous lobes at higher frequencies are clearly revealed by the continuous recordings. Studies on cylinders and spheres in 2‐ and 3‐dimensional arrays have been investigated. It is hoped that generalizations drawn from these results will lead to suggestions for mathematical approaches to solutions. [This work was supported by a Research Grant from Temple University.]