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An experimental study is carried out on the influence of acoustic emission on the development of turbulent flow in He II at temperature 370 mK and at various pressures, from the saturated vapor pressure to that of 4He crystallization. The experimental technique of oscillating quartz tuning fork was applied for simultaneously exciting both superfluid flow, near the oscillating tuning fork prongs, and the acoustic wave emission. The flow rate of He II and the amplitude of the radiated acoustic waves were driven by the fork prongs, excited by voltage oscillations. Furthermore, the power of an acoustic wave depends on the density and sound velocity in He II as ρ/c 5, which in turn depends on the pressure. This allowed to measure the influence of the amplitude of acoustic emission on the flow in He II. It has been shown that the occurrence of acoustic radiation by tuning fork leads to an increased flow velocity for the beginning of nonlinear flow regime.