Abstract: A loudspeaker has a diaphragm with a voice coil disposed about its perimeter and extending in a gap into which the flux of an annular rare earth magnet is focused. An opening behind the diaphragm communicates through the speaker frame. The voice coil may have two or more windings that are connected in parallel, and may, e.g., be layered on top of one another, so that the impedance of the coil, as well as its depth in the front/back direction of motion, are low. The voice coil is preferably implemented using a polyamide form or bobbin, which has patterned lead-in conductors embedded therein to bring power to wire windings on the perimeter of the coil. The lead-in conductors extend to, or through, the central opening of a ring magnet, providing a robust ribbon input connection.
Abstract: A hearing aid to be worn completely in the auditory canal and is adaptable to an individual auditory canal, is individualized by casting of a body in an auditory canal or in a model of an auditory canal. The body is cast in a casting cavity (15) at least partly confined by an extensible membrane (14). In its general condition, before or especially during casting, the inventive hearing aid carries a positioning tip (20) which surrounds the innermost part of the hearing aid radially completely. This positioning tip (20) which is designed to have the form of a tube or of a cap serves for centering the innermost part of the hearing aid when it is introduced into the auditory canal or into the model of such a canal for individualization. After the casting of the body the positioning tip (20) is removed.