U v.1 Series 18 *USED*

This is a used product that has been professionally rebuilt here at Sundown Audio. It comes with a non-doa warranty only. That means they are guaranteed to work when you receive it but no further warranty afterwards. Let us know within 24 hours of delivery if this product has an issue. We will not warranty any used subwoofer after that time. These potentially have scratches & scuffs on the magnets/motors and will not be in new condition. The Sundown U Series is our premier “standard suspension” woofer series. It is the most direct replacement for the world famous Z v.3 woofer line which we produced from 2011 to 2016 before launching the “new platform” Z v.4 series. Due to numerous advancements in our design process the U Series is able to deliver performance on-par with the Z v.3 series but at a much lower cost. We start with a double-stacked / 8.66” wide Y35 grade ferrite magnet system coupled to a one-piece, bumped T-Yoke and a 0.6” thick top-plate. Just as with the Z v.3 before it and our other high-end subwoofers we also add a very thick (5mm thickness) aluminum shorting ring inside the magnets to reduce static inductance and level out inductance over stroke. The U series motor also features a 0.6” long pole-extension to keep the coil under control at high levels of excursion. The voice coil is a 2.36” long / 3” diameter 4-layer aluminum winding / aluminum former unit – which is the same coil we use in our X v.2 series and, thus, the U series has the same 1500-watt RMS ratings. The coil temperature is kept in check by a heavily smoothed / high-velocity pole-vent and a series of ten direct air-gap vents in the back plate. The U series also features newly tooled cast aluminum vent rings in between the frame and top plate to effectively exchange air at a high velocity over the voice coil beneath the spider landing. The U series features an all-new cast aluminum frame series to the Sundown line which allows for taller cones than the older frames used on the Z v