Abstract: An electromagnetic transducer such as an audio speaker which includes an asymmetric diaphragm to deliver smooth frequency response with reduced distortion by reduction of common modes in the diaphragm. Other benefits such as asymmetric directivity patterns can be realized. The asymmetric cone has a perimeter OD at which a surround may be coupled, and an ID at which a bobbin or spacer may be coupled. The center of the ID is not coincident with the center of the OD. The transducer further includes a stabilization mechanism for reducing rocking of the diaphragm assembly. The stabilization mechanism may include mass balancing of the diaphragm and/or adjustments to the location or symmetry of the suspension components.

Abstract: An electromagnetic transducer, such as an audio speaker, includes a return path member which is a pole piece for external magnet geometries or a cup for internal magnet geometries. The magnetic flux return path for the primary drive magnet is through a first portion of the return path member. A first section of a low reluctance magnetic flux return path for a secondary drive magnet is through a second portion of the return path member. A magnetically conductive plate provides a second section of the low reluctance return path from the second portion of the return path member to the secondary drive magnet.

Abstract: An acoustical transducer such as an audio loudspeaker or a microphone, having a suspension component whose outermost edge extends axially rather than radially and couples with an axial mounting surface in the transducer's frame rather than with a radial flat surface of the frame. The suspension component may be a surround or a spider. Eliminating the radial portions of the suspension component and the frame enables the use of a larger diaphragm within a transducer of unchanged outer dimensions, increasing the amount of air moved by or moving the diaphragm. It also enables closer on-center packing of multiple transducers onto the same baffle such as the front baffle of a speaker enclosure, or, put another way, it enables a higher percentage of the mounting baffle's front surface area to be covered with moving diaphragm area. Radial mounting flanges and their mounting holes are limited to portions of the frame which will not increase the gap space between adjacent transducers or other boundaries.

Abstract: An electromagnetic transducer such as an audio speaker, having an improved geometry in the positioning of its voice coils relative to its magnetic air gaps, facilitating a greater linear travel. The transducer has a push-pull geometry with at least two voice coils. At all positions throughout the linear travel region, less than 100% of the total voice coil windings are active, and less than 100% of the total available magnetic air gap height is active. As the voice coil assembly moves in one direction, the percentage of active windings or magnetic air gap is seamlessly handed off from the upper voice coil or magnetic air gap to the lower voice coil or magnetic air gap, and vice versa in the opposite direction. Some of the available voice coil windings and some of the available magnetic air gap height are left unused throughout the linear travel region, but, in exchange, the distance of the linear travel is dramatically increased.

Abstract: An electromagnetic transducer such as an audio speaker, having a push-push geometry in which there are two or more air gaps and the magnetic flux across the air gaps is in the same orientation. If there are more than one voice coil, the voice coils may thus be generating the same electromagnetic polarity by being wound in the same direction about the bobbin, or by being wound in opposite directions and having separate, opposite polarity electrical connections. The transducer exhibits high linearity over a long travel.

Abstract: An electromagnetic transducer such as an audio speaker exhibiting highly linear performance over a greatly extended excursion. The motor structure includes a stack of two or more magnet and plate pairs, with the magnets polarized in the same orientation such that the magnetic flux flows in the same direction over all of the magnetic air gaps. The voice coil is handed off from gap to gap with a configuration providing a substantially constant BL over an end-to-end distance at least as large as the thickness of one plate plus twice the thickness of one magnet.