You can choose the finest components for building loudspeakers, but without consistent, durable, well-designed voice coils the end result will be disappointing. Eminence has been committed to developing and perfecting our voice coil manufacturing techniques for nearly 35 years. For that reason, we are well known for producing the world's finest voice coils.
Many techniques, specialty equipment, and specially designed materials have been developed by or for Eminence to make our voice coils more consistent and durable than those of other manufacturers. Currently we use a specially formulated Kapton ? polyimide film, developed by DuPont to Eminence specifications for most voice coil bobbins or formers. Kapton? prevents excessive heat at the cone apex so thermal failure is virtually eliminated. Consequently, an Eminence loudspeaker's resilience to user error or abuse is extraordinary. Paper bobbins are still used in many applications when vintage qualities are desired.  Consistency plays a critical role in manufacturing voice coils for the best amplifier and cabinet manufacturers in the world today. Every speaker must remain consistent with its original design; otherwise the performance of the finished product will be compromised. Much of the specialty equipment developed by Eminence contributes to this consistency. We use this equipment to control and monitor winding lengths and the number of wire turns on each coil, apply special coatings to wire, activate adhesives, and cut and wind bobbin materials to exact specifications.
 Eminence produces a range of seven voice coil diameters from 1¡± to 4¡± with 1-layer ¡°edgewound¡± and 2, 4, or dual 2-layer coils. Although mechanical factors enter the equation, power handling is largely determined by the voice coil diameter. Typically, a larger voice coil provides greater surface area for better heat dissipation. Special polyimide adhesives, together with the special Kapton? and the Eminence production processes, mean that simply increasing voice coil size to increase power handling may not be necessary. |
