Patent ID: 8892174

Claim:
A loudspeaker comprising: a voice coil; and a diaphragm attached to the voice coil, the diaphragm having a generally rectangular outer shape and comprising: an outer rim area having an outer edge and an inner edge, the diaphragm being fixed in position at the outer edge; and an inner section surrounded by the outer rim area, the inner section comprising: an outermost area adjacent to the outer rim area and coupled to the voice coil, the outermost area having the same generally rectangular outer shape as the diaphragm; and an inner area surrounded by the outermost area, the inner area comprising; a central rib area having a plurality of ribs in a periodic pattern, the ribs being oriented parallel to the shorter sides of the outermost area; and two lateral transition areas between the edges of the central rib area and the shorter side edges of outermost area.