Varieties in results obtained from similar wave distribution experiments in light of environment's geometry have been subjects of many studies. One such difference has been observed while using small coupons or belts as experiment samples in comparison with bigger sheets in industrial scale. The difference in question is perhaps more noticeable here than in any other application. A principal contributor to the existence of such differences is known as Back Wall effect. This phenomenon, in addition to strengthening the signal energy and increasing the number of peaks with same thresholds of signal recording, changes the frequency content of the analyzed signal within the designated time frame. In this investigation, simulation of similar conditions are carried out by generating acoustic waves within an aluminum sheet to study the Back Wall effect received from the outermost wall through wavelet analysis. Obtained results from this investigation however, will not only be limited to small coupons or belts alone. They are extendable to long sheets at the time of sensor installation at sidewalls.© (2011) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.