Abstract: An apparatus for generating shock waves, especially for medical application, creates a spark discharge between two electrodes in a liquid medium. At least one of the electrodes is moveable between a first limit position that corresponds to the smallest possible distance between the two electrodes, and a second limit position that corresponds to the largest possible distance between the electrodes.

Abstract: The invention is for an apparatus for the generation of shock waves, especially for medical application, by means of a spark discharge between two electrodes (6, 7) within a liquid medium with appliances for the movement (216) of at least one of the electrodes (6, 7) along a specified direction of movement, for an electrode unit for the generation of shock waves with two electrodes (6, 7) positioned within a liquid medium and to which a high voltage can be applied for the generation of an electrical disruptive discharge, for a procedure for the calibration of distances for a pair of electrodes (1; 201) for the generation of shock waves by means of an under water spark discharge and for a procedure for the generation of shock waves by means of an under water spark discharge between two electrodes (6, 7).