The present invention relates to an oscillator, particularly for or in a flat loudspeaker, particularly for use in the aerospace field, comprising an oscillating part carrier, a coupling ring for coupling the oscillator to a sound converter of a loudspeaker, wherein the oscillating part carrier and the coupling ring are connected to each other via a detachable quick-release closure, comprising first closing elements for a locked, secure connection in relation to vibrations and second closing elements that are separate from the first closing elements, for a secure connection between the oscillating part carrier and the coupling ring. The invention further relates to a flat loudspeaker comprising such an oscillator and to a vehicle comprising such a flat loudspeaker.