ULTRA-LOW PROFILE LOUDSPEAKERS

The invention provides in some aspects a loudspeaker comprising an enclosure, a driver that is mounted in the enclosure, and an active diaphragm that is coupled to the driver to generate frontward-directed sound waves ("front waves") directed outwardly from the enclosure and backward-directed sound waves ("back waves") directed inwardly into the enclosure. A foam member, disposed within the enclosure and/or on an inner surface of a wall thereof, attenuates components of the back wave as a function of frequency, e.g., in the manner of a low-pass filter. The foam member comprises a foam of rigid material, namely, by way of example, a foam of metal, ceramic, carbon, silicon, glass, and/or epoxy. It (the foam member) may be disposed adjacent the reflective member and, indeed, together those members may comprise one or more walls of the enclosure, e.g., with the reflective member forming an outer surface of the wall(s) and with the foam member forming an inner surface. A reflective member, which is also disposed any of within the enclosure or on an inner surface of a wall thereof, reflects one or more components of the back wave that have passed through the foam member and that have not been eliminated thereby.