Wide-band loudspeaker having a diaphragm area divided into sub-areas for various frequency ranges

Claim 1

A wide-band loudspeaker comprising: a diaphragm area divided into at least two sub-areas, including an inner diaphragm sub-area and an outer diaphragm sub-area, each of said diaphragm sub-areas being optimized for the production of a different portion of an audio frequency range; wherein said inner diaphragm sub-area includes a moving-coil cover connected to a moving-coil support; wherein said outer diaphragm sub-area is coupled to an inner diaphragm sub-area by a connection means which has a frequency dependent modulus of elasticity so that said outer diaphragm sub-area remains substantially at rest when said loudspeaker is generating high frequency audio signals and so that said outer diaphragm sub-area moves substantially in unison with said inner diaphragm sub-area when said loudspeaker is generating low frequency audio signals; wherein when said loudspeaker is generating intermediate frequency audio signals, movement of said outer diaphragm sub-area is partially responsive to movement of said inner diaphragm sub-area via said connection means, said connection means dissipating, by internal friction, a portion of the mechanical energy received from said inner diaphragm sub-area, wherein said outer diaphragm sub-area is constructed in a form selected from a group consisting of a cone diaphragm, a NAWI diaphragm, a shaped body, and a molded body; wherein said selected form is planar at the front and rear boundary thereof; and wherein said outer diaphragm sub-area is of a sufficient height that said selected form is stressed by a force normal thereto, but is substantially unstressed by flexing or tilting forces.