


Sundown Audio X v4 18 Single Bundle (Baltic Birch)
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How this package ships
- Two separate deliveries. Your subwoofer ships from JS Ultimate Sounds and usually arrives first.
- Separate tracking numbers. You will get one for each delivery, so a tracking link showing only part of your order is normal.
- The enclosure is built to order by Basshead Supply and ships direct from them in about 2 to 3 weeks.
- The subwoofer is not pre-installed. You mount it in the enclosure once both have arrived.
- The enclosure arrives finished in a gray stain, ready to install.
What is included
- (1) Sundown Audio X-Series XV4 18" 3000W RMS Subwoofer
- (1) Sundown Audio XV4 18" Single Ported Subwoofer Enclosure, Baltic Birch
Priced 10% below buying the subwoofer and enclosure separately.
Choose your impedance below.
Sundown Audio X-Series XV4 18" 3000W RMS Subwoofer
- Power — 3,000W RMS / 6,000W peak
- Voice Coil — X v.4 coils, available Dual 1Ω or Dual 2Ω
- Xmax — 30mm for deep excursion
- Motor — Heavy-duty 9.25″ diameter
This Listing Includes: (1) Sundown Audio X-Series XV4 18″ Subwoofer
The Sundown Xv4 18″ subwoofer delivers serious power and control, handling 3,000W RMS and 6,000W peak with high-grade X v.4 coils. A heavy-duty 9.25″ motor and large cone area (SD 113.41) move massive air for powerful low-frequency response, while 30mm of Xmax keeps deep bass clean. It works in sealed or ported enclosures with a recommended port tuning of 32Hz, giving you flexibility for SPL competition or everyday high-quality listening. Available in Dual 1Ω or Dual 2Ω, the Xv4 18″ is built for extreme durability and clean sound.
Features
- 18″ X v.4 Series subwoofer, 3,000W RMS / 6,000W peak
- Dual 1-Ohm or Dual 2-Ohm voice coil options
- Heavy-duty motor with 9.25″ diameter
- 30mm Xmax for deep bass response
- Sealed or ported enclosure compatibility; recommended port tuning 32Hz
Specifications
| RMS Power | 3,000W |
| Peak Power | 6,000W |
| Impedance | Dual 1Ω or Dual 2Ω |
| Voice Coil | X v.4 |
| Xmax | 30mm |
| Motor Diameter | 9.25″ |
| Cone Area (SD) | 113.41 |
| Recommended Port Tuning | 32Hz |
Sundown Audio XV4 18" Single Ported Subwoofer Enclosure
- Net Volume - 7.0 cu ft
- Tuning - 30.0 Hz
- Port Area - 101.25 sq in
- Sub Cutout - 16.69"
- Construction - 1" (24mm) plywood construction
This Listing Includes: (1) Basshead Supply ported enclosure for the Sundown Audio XV4 18" subwoofer
This enclosure is custom built specifically for the Sundown Audio XV4 18" subwoofer. Basshead Supply's Performance Series enclosures are subwoofer-specific boxes engineered for strong, clean output, built with a refined assembly process that leaves no visible screw holes. Every box is glued with Titebond III and internally braced, then pre-wired with a recessed satin-nickel binding post and OFC 10-gauge wire - built by hand in the USA. Custom built to order by Basshead Supply and shipped directly from them, about 2 to 3 weeks.
Features
- 1" (24mm) plywood construction
- 17 ply birch veneer construction
- Gray stained finish
- Refined assembly - no visible screw holes
- Glued with Titebond III and internally braced
- Pre-wired recessed satin-nickel binding post with OFC 10-gauge wire
- Built by hand in the USA
Specifications
| Net Volume | 7.0 cu ft |
| Tuning | 30.0 Hz |
| Port Area | 101.25 sq in |
| Port Dimensions | 18.0" x 5.625" |
| Sub Cutout | 16.69" |
| Construction | 1" (24mm) plywood construction |
| Finish | Gray stained finish |
| Wiring | Pre-wired metal binding post with 10ga OFC wire |
| Dimensions (HxWxD) | 20.0" x 39.875" x 25.125" |


