Anodic stripping voltammetry experiments were carried out in aqueous lead solution using square wave voltammetry at insonated mercury thin film electrodes and compared to numerical theory developed in an earlier paper (Ball, J. C.; Compton, R. G. J. Phys. Chem. B 1998, 102, 3967). Excellent agreement was obtained under very fast mass transport conditions corresponding to the small (similar to micrometer) diffusion layer thickness obtained under power ultrasound. The results provide further confirmation that the dominant contribution to the mass transport arises from diffusion layer thinning due to acoustic streaming except under extreme conditions. The choice of optimal square wave frequency under these conditions was investigated.