Sundown Audio U-Series v.1 10" D4 Subwoofer: High-Performance BassThe Sundown Audio U-Series is the premier "standard suspension" woofer series, engineered to maximize power handling and longevity while being cost-effective. The U-Series is designed to be a direct replacement for the Z v.3 line and is built to withstand demanding music enjoyment and competition use.
The U-Series motor is built for robust 1500W RMS power handling:
Voice Coil: Uses a 2.36" long / 3" diameter 4-layer aluminum winding on a Black Aluminum former for superior heat dissipation.

Magnet System: Features a double-stacked / 8.66" wide Y35 grade ferrite magnet system coupled to a one-piece T-Yoke.

Excursion: Achieves 30mm Xmax with a 0.6" long pole-extension to keep the coil under control.

The design includes specific features to maintain control and temperature under high power:
Inductance Control: Features a 5mm thick aluminum shorting ring inside the magnets to reduce static inductance.

Venting: Coil temperature is regulated by a heavily smoothed high-velocity pole-vent, ten direct air-gap vents, and innovative cast aluminum vented frame spacer rings.

Frame: Built on an all-new cast aluminum frame that allows for taller cones, providing enhanced coil stability.

The SW-UV110D4 features a Dual 4-Ohm configuration:
DC Resistance (Re): 6.1 Ohms

Resonance Frequency (Fs): 41.1 Hz

Total Q Factor (Qts): 0.35

Sensitivity: 84.9 dB @ 1w/1m

BL (NA): 29.7

Mounting Depth: 7.007 inches

Recommended Enclosure: Optimized for 0.5 cu ft sealed or 1.0 cu ft ported enclosures. Recommended Port Area is 16 sq in.

The subwoofer includes cast Aluminum surround bolt-on rings, heavy duty cast basket, and spring loaded terminals that accept up to 8 gauge wire.