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To clarify the effects of air jet conditions controlled by flutists on acoustic radiation, experiments were performed by an artificial blowing device with an artificial oral cavity. The experimental parameters are the flow rate, the jet angle between the jet issuing from the cavity exit and the surface of the mouth hole, the jet offset to the edge and the distance from the cavity exit to the edge. Each parameter was changed independently. The reference values for the conditions were determined by referring to the actual playing conditions, of which jet angle was measured by the Schlieren method in this research. The Reynolds number based on the cross-sectional mean velocity and jet height was changed from 1700 to 2560 by adjusting the flow rate. In this range, as the flow rate was increased, the fundamental frequency became higher, keeping the first acoustic mode. The fundamental frequency became lower for the larger jet angle within the intense radiation. When the cavity exit was biased outside the edge by the jet height, the second harmonic became more intense while the fundamental frequency was approximately constant. The shift of the fundamental frequency to the higher mode was observed for a longer jet distance.