Sound wave treatment device

A sound wave treatment device (1) for medical treatment using compression waves, in particular for lithotripsy, having:

• a sound wave generator (2),
• a plurality of piezo elements (7) that are coupled to the sound wave generator (2), and,
• an electrical high voltage unit (20) that is set up for supplying the piezo elements (7) with high electrical voltage
• wherein
• the high voltage unit (20) has a blocking converter unit (22) having a transformer (24), wherein the transformer (24) has a primary coil (L1), a high voltage coil (L4), and spacers (48), wherein the high voltage coil (L4) has a plurality of high voltage windings that are embedded in an insulating mass (46) and are positioned using the spacers (48) such that adjacent high voltage windings are at a defined distance (a) from one another due to the spacers (48), wherein the high voltage coil (L4) is wound on a high voltage coil former (38) and the spacers (48) are a thread on the high voltage coil former (38), wherein an entire circumference of each high voltage winding is embedded in a V-shaped groove (52) of the thread, each V-shaped groove (52) has centering surfaces (54) that urge the respective winding into a specific position, and wherein lands (50) of the thread project beyond a wire diameter of the high voltage coil (L4) between adjacent high voltage windings, wherein the transformer (24) has a first auxiliary coil (L2) for indirectly measuring the output-side high voltage, wherein the transformer (24) has a second auxiliary coil (L3) that is for redundant indirect measurement of the output-side high voltage and that is arranged parallel to the first auxiliary coil (L2), and wherein the first auxiliary coil (L2) and the second auxiliary coil (L3) are embodied as foil coils parallel to one another.