This paper describes the process of creation of a new digital musical instrument: Osiris. This device is based on the circulation of liquids for the generation of musical notes. Besides the system of liquid distribution, a module that generates MIDI events was designed and built based on the Arduino platform; such module is employed together with a Proteus 2000 sound generator. The programming of the control module as well as the choice of sound-generating module had as their main objective that the instrument should provide an ample variety of sound and musical possibilities, controllable in real time.