Down4Sound PRO-FAB - Birch - 4X 8-INCH Ported Subwoofer Enclosure - 99-07 GM/CHEVY Extended CAB - 2.5-INCH Seat Lift Required
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Most products are covered by the manufacturer's warranty against defects. Damage from over-powering or improper installation isn't covered — we'll help coordinate any valid claim.
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Subwoofer Wiring Diagram
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Tailored for the 1999-2007 GM/Chevy Extended Cab, this Down4Sound PRO-FAB enclosure is designed for serious bass enthusiasts. Featuring four 8-inch subwoofer openings, it delivers precision-tuned bass output with a tuning frequency of 32.5 Hz. Crafted from premium birch wood and finished with a durable polyurethane bedliner, this enclosure is built to withstand high-performance demands. A 2.5-inch seat lift is required for proper installation.
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Compatibility
1999-2007 GM/Chevy Extended Cab (Under Seat, 2.5-Inch seat lift is required BUT IS NOT INCLUDED) -
Configuration
Quad 8-inch subwoofer openings -
Material
Premium birch wood with polyurethane bedliner coating for enhanced durability
Outside Dimensions
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Width
55 inches -
Front Height
9 1/2 inches -
Rear Height
12 1/2 inches -
Depth
14 3/4 inches
Net Airspace (After Displacements)
1.29 cubic feet per sidePort Information
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Port Area
10.98 square inches each -
Port Depth
12 1/2 inches -
Tuning Frequency
32.5 Hz
Recommended Subwoofer
Optimized for Down4Sound DBz 8" SubwoofersThis enclosure is the perfect fit for upgrading your GM/Chevy Extended Cab’s audio system, providing exceptional durability and bass performance for high-output setups.
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