The present invention relates to an output stage for adapting an AC voltage signal of an ultrasound generator to a converter connectable to the output stage, wherein the output stage has two input terminals for receiving the AC voltage produced by the ultrasound generator and two output terminals for outputting an adapted AC voltage, as well as an output transformer with a primary coil having a number n1 turns and a secondary coil with a number n2 turns, the output transformer having a main inductance LH as well as a leakage inductance Lσ, the two input terminals being connected to one another via the primary coil and the two output terminals being connected to one another via the secondary coil. In order to disclose an output transformer, which allows an economical and uncomplicated adaptation of a generator output to the converter input, it is proposed according to the invention that a filter capacitor CP is provided, which either connects the two output terminals in parallel to the secondary coil or connects an output terminal to a tap of the secondary coil or is connected to a filter coil with n3 turns, which is inductively coupled to the primary and the secondary coil.