The noise field generated by the motion of one, two, or several rectilinear vortices in an inviscid, irrotational mean flow past a step is considered for low Mach number. The streakline patterns of an impinging vortex are compared with flow visualization studies, and qualitative agreement between the present analytical results and the experiments is achieved. Both acoustic pressure and intensity are strong functions of the vortex motion near the step which, because of the complexity of the geometry, must be computed numerically. Results for the acoustic pressure and intensity are presented for a variety of incident vortex arrays.