This new unit maintains a precise engineering balance between the voice coil, spider and surround that produces linear motion of all three for lower distortion by incorporating CAD/FEA optimized high-linearity motor geometry:
The extremely long (50mm) two-layer copper voice coil gives this transducer a very high Xmax, dramatically increasing output. A fiberglass voice coil former helps the voice coil withstand high temperatures, reducing power compression and helping increase output. A cardboard spacer added at the top of the voice coil former maintains motor geometry, creates a solid attachment joint and prevents deformation of the voice coil at high outputs. The spacer also eliminates the typical single fulcrum point between the spider and cone on the voice coil former, minimizing voice coil rocking modes during hi-power operation.
A high-temperature nomex spider features a progressive roll design that evenly distributes mechanical stress, helping keep the cone’s motion linear during high excursion operation.
A nitril/butylene rubber surround uses patented Plus One® technology that increases the transducer’s radiating area (Sd), increasing volume displacement and output.
The coated cellulose/pulp cone and dustcap assembly is vented under the dustcap to aid in the exchange of air, which reduces acoustic losses and increases output.
The transducer’s magnet assembly features a triple-stacked vented ceramic 5 magnet with flared vents that reduce turbulence, which improves airflow, increases output and reduces distortion. Dual symmetrical magnet shorting rings and an extended top pole create a symmetrical magnetic gap field that increases power handling and reduces power compression further increasing output. A 15mm-thick top plate improves heat and flux distribution for lower distortion.

The cast aluminum frame is fully vented to minimize acoustic losses caused by excessive back pressure. This frame also maintains dimensional stability and precise mechanical tolerances, allowing the transducer to be manufactured and assembled to a high degree of precision.

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