Custom Subwoofer Enclosure for Sundown Audio Xv3 18" – Massive 7.0 ft³ Ported Box

Built to unleash the raw power of the Sundown Audio Xv3 18" subwoofer, this custom enclosure from Basshead Supply is purpose-engineered for deep, thunderous bass response and rugged durability. If you're pushing serious watts and demand uncompromising SPL, this precision-tuned 18-inch subwoofer box is the ultimate upgrade for your build.

Performance Specifications – Xv3 18" Subwoofer Enclosure

• Net Internal Volume: 7.0 cubic feet
• Tuning Frequency: 30 Hz – optimized for low-end extension and musical bass
• Port Area: 95.64 square inches
• Port Dimensions: 18″ x 5.33″
• Subwoofer Cutout Diameter: 17.01″
• Power Handling: Designed for high-power subwoofer setups (over 2000W RMS)

Premium Construction & Materials

• Material: 1” thick Russian Baltic Birch plywood throughout
• Build: 17-ply birch veneer – ultra-dense and ultra-strong
• Assembly: Seamless, screwless exterior using industrial-strength Titebond III adhesive
• Finish: Carbon gray stain with protective polyurethane clear coat
• Pre-Wiring: Pre-installed 10-gauge OFC wire with recessed satin nickel brass binding posts

Enclosure Dimensions

• Height: 20″
• Width: 39.75″
• Depth: 24.625″

Custom Built-to-Order – Production & Return Policy

Build Time: 2–3 weeks from order date (custom fabrication)
No Refunds: Once your enclosure has been cut, all sales are final

Handcrafted in the USA – Basshead Supply Branded Series 🇺🇸

This Sundown Xv3 18" custom enclosure is part of our elite “Branded Series” lineup—built by hand in the United States using industry-leading materials and construction techniques. From the full 1-inch birch construction to the stain-and-clearcoat finish, this box is made to outperform and outlast prefab alternatives.

Whether you're building a demo rig, entering SPL lanes, or just need to get the most out of your Sundown 18", this high-output ported enclosure is the perfect match. With clean lines, premium craftsmanship, and tuning optimized for real-world bass, it’s ready to shake the ground the moment it arrives.

Order today and equip your build with an enclosure that delivers on every front—looks, strength, and performance.