Thanks for self-moderating, guys. SVS isn't targeting a specific OEM with the introduction of the SB13-Plus and the SB16-Ultra. We're simply fleshing-out our sealed box line-up, and offering three different size/price/performance levels just like our bass reflex box/cylinder line-up.
Regarding overhung/underhung - the overhung topology makes more sense in the smaller SB13-Plus, where the air spring is stiffer and we need a lot of BL from the motor.
In the larger SB16-Ultra, we were able to use an underhung coil with a lightweight radial neo motor which provided the best combination of BL, woofer Q, and extremely low distortion (a hallmark of the underhung design) working against a more compliant air spring.
Along the same vein, the large enclosure of the PB13-Ultra is one of the reasons the 13.5" underhung woofer works so nicely in sealed mode, with an excellent power response and virtually no output compression. That particular woofer isn't well suited for sealed operation in a much smaller box, so switched to an optimized overhung motor for the SB13-Plus, while retaining the basket/cone/surround from the underhung 13.5" Ultra woofer.
The 16.5" underhung radial neo woofer OTOH is a completely new clean-sheet design. And yes - this woofer obviously has potential for use in other subwoofer applications besides the SB16-Ultra.
Director - Technology and Customer Service
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