These Sundown Audio U-6.5 V.1 D4 6.5" car subwoofers are built for compact installations where space is limited but strong low-frequency output is still the goal. Each sub is rated at 500W RMS/1000W peak and uses dual 4 ohm (DVC) coils for flexible wiring, while the design focuses on thermal management and durability for demanding daily use.

Key details:

6.5" subwoofer pair with 500W RMS/1000W peak per sub and dual 4 ohm (DVC) impedance

Aluminum 1.75" voice coil former with a high-temperature copper voice coil

Cooling-focused motor details including vent channels, rear gap-venting, an aluminum shorting ring cap, and top-plate cooling channels

Double stitched surround, heavy-duty cast basket, and stitched heavy-duty tinsel leads

Spring-loaded terminals that accept up to 8-gauge wire

Enclosure guidance: ported 0.25 cu ft tuned to 35 Hz (4-5 sq in port area) or sealed 0.125 cu ft, plus 4th order specs listed at .09/2.25 cu ft with a 6" port length

For planning your install, the U-6.5 V.1 D4 measurements include 5.71" mounting depth, 5.94" cutout, 5.51" motor diameter, 0.04 displacement, and Fs 38.6925 Hz.