A composite membrane acoustic transducer structure comprising a magnet assembly is arranged adjacent the composite membrane material. The magnet assembly is arranged to produce a flux field. A first layer of thin, elongate composite membrane material is held under tension. A second conductive layer is attached to the first layer of composite membrane material wherein the first and second layers of membrane material are arranged adjacent, generally parallel and offset from the magnet assembly. The assembly is arranged to produce the flux field through at least part of the first layer and the second layer.