Optimal orientation angles and aspect ratios of a grain are presented for the attenuation of a longitudinal pressure wave by elastic stresses that arise from the rotation of a grain. A computer program in C++ allows the grain to be a two-dimensional ellipse of several orientations with respect to the incoming load. The program also varies the aspect ratio of the grain. The induced elastic stresses from the rotation of the grain are calculated with complex variable methods that do not require meshes and elements. Low aspect ratios of 5/3, 10/7 and 5/4 were particularly effective in halting the stress from the pressure wave when the major axis of the grain was tilted between 15° and 45° and again above 70° with respect to the line of the incoming load. Attenuation was found to be more sensitive to grain orientation than to aspect ratio. The conclusion is supported by numerous switches in the extent of wave blockage over small angular variations in the orientation of the grain.