Previous theoretical studies indicate that the influence of Poisson′s ratio and shear deformation on the propagation characteristics of the longitudinal wave cannot be neglected, and the area ratio between the two ends of a rod may also affect the propagation characteristics. Here, an experimental system is designed, and corresponding experiments are performed in order to verify the theoretical study. A good agreement between the experimental results and theoretical predictions is obtained, i.e. for the present rod with variable cross-section, the Poisson′s ratio and shear deformation led to a higher cut-off frequency, and a higher area ratio between the two ends of the rod also resulted in a higher cut-off frequency. The conclusion contributes to our understanding of real vibration signals and provides a foundation for condition monitoring and noise control.