• Expertly paired subwoofers, enclosure, and amplifier for optimal performance and synergy.
• Due to the nature of the items in this package, each item will be shipped individually.
• GP/Tru-Spec Enclosures assembled in the USA.
• Includes a FREE 2-Year Extended Accidental & Repair Warranty card that covers all electronics in this package.

Sundown Pair of 12" U-Series D4 Subs, ATOM 3.5K Amp w/ Dual Vented Enclosure

This Listing Includes:

• (1) Dual 12" Vented Subwoofer Enclosure


• (2)  12" U-Series Sundown Subwoofers


• (1) Apocalypse ATOM 3.5K PRO Power Amplifier

Subwoofer Features:

• Black Aluminum 3" voice coil former for superior heat dissipation


• High Temperature Round-Wire ALU voice coil with high-temp black adhesive


• Double stitched surround


• Heavy duty cast baskets - all new, custom-tooled


• Spring loaded terminals accept up to 8 gauge


• Stitched-on double-XL tinsel leads


• Solid pole with vent channels and aluminum shorting ring cap


• Rear drilled gap-venting


• Innovative high-velocity cast aluminum vented frame spacer ring


• Magnet ID shorting ring


• Top-Plate Cooling Channels


• Cast Aluminum surround bolt-on rings


• Optimized for small ported or bandpass enclosures

Subwoofer Specifications U12 D4:

• RE (Ohms): 6.0577


• FS (Hz): 41.9087


• VAS (L): 14.7535


• Qes: 0.5870


• Qms: 4.9022


• Qts: 0.5242


• Le (mH): 4.3694


• BL (NA): 31.1265


• Mms (Grams): 356.5462


• Cms (uM/N): 40.4498


• Sens (dB @ 1w/1m): 84.4191

Amplifier Specifications:

• Model: ATOM 3.5K PRO


• Class: D


• Number of Channels: 1


• Frequency Response: 10 - 250 Hz


• 1 Ohm RMS Power (14.4 V): 3500 W


• 1 Ohm RMS Power (12 V): 2900 W


• 2 Ohm RMS Power (14.4 V): 2200 W


• 4 Ohm RMS Power (14.4 V): 1210 W


• Minimum Permissible Load on the Channel: 1 Ohm


• Low Pass Filter: 80 - 20000 Hz


• Crossover: 12 dB/Oct


• Subsonic Filter: 10 - 80 Hz


• Bass Frequency Adjustment: 35 - 90 Hz


• Input Terminal: 0 Ga


• Output Terminal: 4 Ga


• Working Voltage: 9 - 15 V


• Signal-to-Noise Ratio: â 85 dB


• Size (WxLxH): 10 x 8.6 x 2.6 inches

Amplifier Features:

• High RMS power for dynamic bass output


• Tailored bass control for customized sound


• Versatile audio shaping with multiple filters


• Compact, efficient Class D technology


• Crystal-clear audio with superior signal quality

Enclosure Specifications:

• Material Thickness: 0.75"


• Net Internal Volume: 3.50 ft3


• Tuning Frequency: 35 Hz


• Port Area: 52.00 inch2


• Cutout Diameter: 11.20"


• Flush Trim Diameter: 13.10"

Enclosure External Dimensions:

• Length: 34.00"


• Depth: 14.00"


• Height: 22.00"