The invention relates to a device for generating a medium stream, having a chamber, which chamber comprises chamber walls lying opposite one another and at least one medium opening for the medium stream, which medium stream can be generated in the chamber by a diaphragm, which diaphragm, in an inactive operating state of the device, is arranged substantially untensioned in the chamber between the chamber walls lying opposite one another, and associated with which diaphragm is a drive device, responsive to electrical drive signals, for driving the diaphragm to deform the same, the drive device being designed to impose a deformation on the diaphragm in an active operating state of the device, during which deformation the diaphragm has an inner mechanical tension.