About: Sundown Audio U Series 8" - 600 Watts RMS
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.3 series. The taller cones provide enhanced coil stability and increased mechanical excursion capability. We also tooled matching cast-aluminum surround clamps for the U series to ensure durability in the most demanding situations. The surrounds and cone bodies have been fully custom tooled especially for the U series and are stronger / support more excursion than the Z v.3 series cones and surrounds. The new cone bodies also feature an indentation for the same wide-flange, ultra-strong dust caps as our new platform subwoofers.
If you are looking for a woofer that sounds similar to the SA series but handles significantly more power… the U series is exactly what you need. It has been designed to live up to the reputation earned by our Z v.3 series both in terms of every-day music enjoyment and SPL competition
- DC Resistance (Re): 6.1228 Ohms
- Resonance Frequency (Fs): 52.7160 Hz
- Zmax: 40.0810 Ohms
- Electrical Q Factor (Qes): 0.6072
- Mechanical Q Factor (Qms): 3.3675
- Total Q Factor (Qts): 0.5144
- Voice Coil Inductance (Le): 5.4104 mH (at 1 kHz)
- Sd: 21408.3884 mm^2 (33.1831 in^2)
- Equivalent Volume (Vas): 2.9629 L
- Force Factor (BL): 25.8651 N/A
- Moving Mass (Mms): 200.2935 g
- Suspension Compliance (Cms): 45.5082 uM/N
- Efficiency: 0.0672 %
- Sensitivity: 80.2899 dB @1w/1m
- Sensitivity: 81.4513 dB @2.82vrms/1m