A mechanical device used to atomize liquids. The device eliminates circular instability at elevated generation frequencies, producing drops of 30-40μ. This is achieved when the central bar has been made with the diameter equal to the diameter of the nozzle. The longitudinal grooves in the central bar are located at the distance which does not exceed the quarter of the wave length of the nozzle working frequency. The depth of grooves at the central bar 8, their width t, number n, the generation frequency f, the width of the resonance groove of the pneumoacoustic bar nozzle a and the distance between the circular gas nozzle H and the bottom of the ring-like resonator were selected based on the ratio: S=n·8·t, where S is the aggregate cross section of grooves upon the preset gas efficiency; 12.5˜f·8˜15; 1.8˜a/8˜2.1; 7˜H/8˜8.