Variations of the pressure field of a jet are simulated numerically by axisymmetric vortex rings with viscous cores submerged in an inviscid uniform stream. The results are compared with the experimental data measured near a jet. The intervals of shedding time between successive vortex rings are first matched with time intervals between successive pressure peaks of the experiments. and then generated by a numerical program to simulate the randomness of the pressure distribution in the acoustic field. This numerical program randomly generates shedding time intervals with the same probability distribution as that given by those measured in the experiments. Statistical comparisons between numerical and experimental results including probability distributions of shedding periods between successive peaks and variations of peak time period of vortex shedding along the cone of measurement are made up to six diameters downstream of the jet. The role played by the axisymmetric model in the pressure field is also discussed.