Abstract: We report the results of experiments of sound scattering by a vortex flow formed behind a grid of vertical cylinders placed in an air flow. The experiments were carried out in a low turbulence wind tunnel at a low Reynolds number. The vortex flow was formed behind a grid of 3-10 of hollow cylinders with the d=2 mm and length 30 mm. During the experiments we could change the gap between the cylinders g=L/d (where L is a distance between the cylinders surfaces) from 3 to 5. The experiments showed that at a certain value of g vortex flows behind different cylinders could synchronize and this effect could be easily detected by means of distant acoustic sensing. This result was also confirmed by means of direct measurements of velocity field of the vortex flow.