The invention relates to a method for impregnating at least one fibre bundle (11) with a high-viscosity plastics material (13), said method comprising the following steps: •—providing at least one fibre bundle (11) for impregnation, formed of a multiplicity of continuous fibres, and providing a plastics material (13), melted at a mandated operating temperature and of high viscosity, and •—impregnating the fibre bundle (11) with the plastics material (13), by guiding the fibre bundle for impregnation continuously through an impregnation cavity (12), filled with the melted plastics material (13), •—where during impregnation of the fibre bundle, the melted plastics material within the impregnation cavity is contacted with a surface (15) of at least one oscillation generator (14) in such a way that sonic energy is introduced by said oscillation generator into the melted high-viscosity plastics material in the impregnation cavity.