The object of the invention is to provide a device for digital hydraulic pressure transformation with low loss, intended for flow—and power control for hydraulic machines, particularly hydraulic cylinders, which via a switching device are connected to a pressure reservoir with constant high pressure. According to the invention an intermediate mass is present between the switching device and the hydraulic machine which mass is activated by the flowing medium, the intermediate mass being of such size that the average velocity of the flow in the pipe during the open period of the switching device is sufficiently low to bring the hydraulic medium into the hydraulic machine so slowly, that the pressure change at the location of the hydraulic machine is smaller than the pressure difference between the reservoir and the momentary pressure at the location of the hydraulic machine, as result of which a gradual stepwise rising or lowering of said pressure level is made possible.