NVX 12" X-Series Loaded Subwoofer Enclosure

400W RMS, 12" X-Series Dual 4 ohm Car Subwoofer with Sealed Subwoofer Box

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NVX X-Series Subwoofer Breakdown

Hybrid Cone

Egyptian Papyrus-Blend Cone

The NVX X-Series features an ultra stiff, lightweight cone material custom made from finely milled pulp & Egyptian Papyrus fibers. The cone is treated with a soft matte black finish for a stylish and modern look.

Vertically Attached oSD Surround

Patented Surround Technology

XQW woofers are engineered with a unique oSD (oversized SD) surround. This patented technology involves attaching the surround on a vertical edge for increased surface area, which translates to more bass. Additionally, the surround itself is constructed with a multi-radius elliptical edge for incredibly symmetrical, linear cone movement.

Aluminum Shorting Ring

Aluminum Shorting Ring

Another feature which seperates the X-Series from other woofers on the market is the innovative aluminum shorting ring. The shorting ring is basically a conductive aluminum ring placed between the pole piece and the voice coil former. This ring will essentially reduce the negative effects of the inductance which is inherently present in any loudspeaker. In short, this shorting ring:

  • Improves power delivery to the voice coil
  • Decreases distortion
  • Contributes to linear cone movement
  • Improves high-end extension
  • Decreases risk of overheating

Optimized for Small Enclosures

Space Efficient Design

These subwoofers only require 6" of mounting depth to produce intensely powerful bass. NVX utilized the latest loudspeaker technology to design a space-saving subwoofer without the anemic sound of typical shallow-mount woofers. NVX claims that the X-Series is "The discerning listener's alternative" to such shallow subwoofers, and we agree.

High Temperature Voice Coil

3" High-Temp Voice Coil

The stout 3" high temperature voice coil is constructed from a copper wire wrapped around an TSV TIL former. This industry standard design is powerful enough to readily drive the cone with strict linear control, yet at the same time remains efficient enough for the compact, space saving magnet structure. The black appearance of the coil is a result of the special treatment which is applied to improve power handling and heat dissipation.

Low Turbulence Basket

Custom Cast Aluminum Basket

The custom basket of the X-Series woofer is striking in terms of both aesthetics and engineering. A particularly open basket was designed in order to improve airflow for superior cone response and reduced back-wave interference. NVX engineers chose aluminum both for its exceptional strength-to-weight ratio, as well as to eliminate interference with the magnet structure.

High-Excursion Tinsel Leads

High Excursion Tinsel Leads

The tinsel leads used in the X-Series woofer are a small example of the incredible attention to detail of the NVX engineers. These tinsel leads are attached at the basin of each fold in the spider with sufficient slack for full excursion. This prevents damage to the leads from the movement of the cone, while also keeping them securely attached to prevent mechanical noise.

NVX XQW124 (Newest Version)

400W RMS, 12" X-Series Dual 4 ohm Car Subwoofer w/ Aluminum Shorting Ring (XQW 124)
Quantity: 1

General Features:

  • 12" Dual 4 Ohm X-Series Series Subwoofer
  • Power Handling:
    • RMS: 400 watts
  • Impedance: 4 ohms
  • Custom blend of finely milled pulp and Egyptian papyrus fiber cone with smooth matte finish
  • Multi-Radius Elliptical edge foam surround
  • Includes oSd surround technology (U.S. Patent #7,031,487) allowing for an extra 8-12% more surface area than competing subwoofers
  • Innovative aluminum shorting ring system with several positive impacts on the subwoofer:
    • Improved power delivery to the voice coil
    • Decreased inductive distortion
    • Improved cone linearity
    • Improved high-end extension
    • Decreased risk of overheating
  • 3" High temperature voice coil designed with an oxygen-free copper coil
  • 123 oz double stacked ferrite magnet
  • Optimal ported enclosure tuning frequency: 34 Hz
  • Frequency response: 20-200 Hz
  • Resonance Frequency (Fs): 29 Hz
  • Top-mount depth: 5-3/4"
  • Sensitivity: 89 dB
  • Authorized Internet Dealer
  • 1-year Manufacturer's Warranty
Tips for Installing the your NVX XQW124 subwoofer


12" Sealed Subwoofer Box Made for NVX X-Series (XQW124/XQW122)
Quantity: 1

General Features:

  • 12" Sealed Subwoofer Enclosure
  • Ideal for trucks and other shallow locations
  • Engineered for the NVX XQW124 & NVX XQW122
  • Carbon-fiber front face board
  • Spring-loaded push terminals also accept banana plugs
  • Covered in high-quality black carpet
  • Durable 3/4" Medium Density Fiberboard (MDF) construction
  • Subwoofer mounting depth: 7-1/2"
  • Subwoofer cutout diameter: 11-7/8"
  • Box volume: 0.94 cubic feet
  • Dimensions: 9-1/4"D x 18-1/2"W x 16-3/4"H
  • Authorized Internet Dealer
  • 1-year Manufacturer's Warranty

Subwoofer Specifications

Subwoofer Series
Each subwoofer manufactured is part of a series. This is the name of the subwoofer's series.
Subwoofer Size
Refers to the diameter of the subwoofer, measured in inches.
Voice Coil(s)
Dual voice coil subs have more wiring flexibility than single voice coils subs; however, single voice coil subwoofers provide easier hookup options for wiring multiple subwoofers in parallel or series. You may also run a dual voice coil (DVC) sub in parallel, series, or combination. A quad voice coil has four voice coils and is equal to two dual voice coil subwoofers as far as wiring goes.
Impedance (Per Voice Coil)
The load value (in ohms) that the speakers present to the amplifier per voice coil - the amount of resistance to the current flow. This is a key specification as subs wired in parallel or low impedances can create problems with your amplifier and potentially void all warranties. We encourage you to ask our support department prior to purchase if you do not understand which impedance level will suit your application best.
4 ohms
RMS Power Handling
The RMS power is the amount of power the speaker requires to operate safely and properly. RMS Power Handling refers to the amount of power a speaker can handle on a continuous basis. We recommend powering your speakers or subwoofer with 80%-120% of its recommended RMS rating. The RMS power handling specification is typically rated per speaker unless otherwise noted.
400 watts
Total RMS Power Handling
This is the total RMS power handling of all the subwoofers included in the package or enclosure.

If the loaded enclosure or amplifier and subwoofer package includes more than a single subwoofer, then this is the total RMS power handling for all of the subs combined.

The RMS power is the amount of power the speaker requires to operate safely and properly. RMS Power Handling refers to the amount of power a speaker can handle on a continuous basis. We recommend giving your subwoofer(s) 75% - 90% of the recommended RMS rating.
400 watts
Woofer Composition
Lightweight woofer cone materials are essential for efficient operation. Poly cones produce exceptional sound and are sturdy against various changes in temperature. Paper cones are very efficient, and when treated for moisture resistance, will perform at a high level. Poly refers to polypropylene, which is thermoplastic or fibers that are polymers of propylene. IMPP refers to injection molded polypropylene, a commonly used process and material in speakers.
Egyptian Papyrus Fiber
Woofer Surround
A speakers surround is part of the suspension system. The surround protects the cone and prevents it from being displaced as it flexes out from the basket. It is usually made of a durable material like treated foam or rubber in order to withstand the strenuous job of producing bass frequencies.
An efficiency or sensitivity rating tells you how effectively a speaker converts power into sound. The higher the number, the more efficient the speaker and the louder it will play with the same input power. An efficient speaker helps you maximize your available power. Most sensitivity ratings measure the speaker's output with 1 watt of input, 1 meter from the speaker. Some speakers' sensitivity is measured with 2.83 volts of input, instead of 1 watt.
Efficiency (1w/1m) is not an accurate indicator of a subwoofer's output capability and should not be used as a comparison to other speakers or subwoofers to determine which one is "louder".
89 dB
Frequency Response
The range of frequencies the speaker will reproduce (lowest frequency to the highest). Bigger is better, meaning the wider the range, the better. The optimal range is 20 - 20,000 Hz (which is the range of human hearing).
20 - 200 Hz
Xmax (millimeters)
Typically measured in millimeters, the Xmax value is the measure of a speaker cone's maximum excursion in one direction while maintaining a linear behavior.
20 mm
Subwoofer Design
This is the design of the subwoofer or the opening of the subwoofer enclosure. Each design has it's own benefits, whether it is a square, circle, or oval.

Round/Circle: This is the typical and common subwoofer design. They have a round cone and are a circle in design.

Square: These woofers are able to achieve a greater cone area in a smaller space. Because of the greater surface area, some square subwoofers will be louder than a round subwoofer of the same size.

Round / Circle

Enclosure Specifications

Box Type
Represents the style of the enclosure. Be sure to purchase the appropriate enclosure type and internal volume that will be compatible with your subwoofer's recommendation.

Sealed - Sealed boxes are those that have no holes or vents in it. The only hole in a sealed box is where the subwoofer is installed. Smaller sealed boxes require more power than a larger sealed box. They provide a tight, accurate bass, while the larger sealed enclosures provide a "boomier" and louder bass.

Ported / Vented - Ported/Vented Enclosures provide an even boomier, louder bass, but less accurate then a small, sealed box. Ported enclosures typically require more airspace per sub and also less power output from an amplifier to perform correctly.

Bandpass - Bandpass enclosures make subwoofers perform efficiently, but loose. The bass is not as "boomy" as a ported enclosure nor as punchy as a sealed enclosure. Bandpass enclosures work well with lower to mid-level subwoofers.
Number of Subs/Speakers
This value represents the number of speakers or subwoofers that the enclosure accommodates.
Box Style/Shape
The box style or shape refers to the actual shape of the box. Square and rectangular boxes are straight-edged boxes on all sides, whereas hatchback and truck style enclosures feature an angled front or back design that allows for installation in places short on depth such as single cab pickup trucks. You can also use such enclosures in hatchback cars or other vehicles where space is a premium. Tube and cylinder shaped boxes were made popular by Bazooka and are a great option for those looking for a nice amount of bass without sacrificing lots of space. They may even fit in locations that slim truck boxes cannot fit in. If the enclosure is vehicle specific, we encourage you to read the product description to find out which vehicles the enclosure is made for.
The height of the item, measured from top to bottom, in inches.
The width of the item from left to right (side-to-side) measured in inches.
The front-to-rear depth of the item, in inches. If the item is angled or slanted, this value is the bottom measurement.
Wood Thickness
The thickness of the wood the enclosure is made of, measured in inches.
Number of Terminals
The number of terminals the enclosure has. Each terminal represents 1 positive and 1 negative.
Terminal Type
Spring clip terminals work best with bare wire connections with small-gauge speaker wire, or pin-type connectors.

Binding post terminals are a sturdier, more versatile type of speaker terminal. Because binding post terminals are are threaded, you can tighten them down against the wire or connector for a tight, clean connection. The most popular style of binding post terminals is known as a "5-way binding post". This type can accept bare wire, or any of the common speaker wire connectors. Binding posts with the option to be used with banana clips are even more versatile

Spring posts are a hybrid of the two. Instead of using a thread and "screwing" them tight, they use a spring to allow the wire to fit and tighten against the terminal.

Spring posts (banana clip ready)
Box Exterior Color
The color of the enclosure's exterior/outer finish.
Box Finish
The material used on the outside of the box. Most boxes are carpeted to prevent exterior scratches; however vinyl is popular as it can often be color-matched to a near exact look of your leather factory interior.

Warranty and Return Policy

Parts Warranty Duration
1 year
Labor Warranty Duration
1 year
Warranty Provider

Summary of Customer Ratings & Reviews

Rating Distribution

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1 Star

Average Attribution Rating

Accessory Tools and Products

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25 ft. of True 12 Gauge EnvyFlex Speaker Cable/Wire (100% Oxygen-Free Copper)

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20 Square Feet of Sound Dampening Material (Five 18" x 32" Pieces)

Your Price $59.99

NVX Sound Dampening Rubber Roller (SDRLR1)

Universal, Professional Heavy Duty Roller for Sound Damping/Dampening

Your Price $7.99

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Complete Car Stereo Tool Kit, Includes Voltage Test Light, Wire Stripper and More

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Sonic Electronix Wiring Guide

Wiring Diagram Legend

Warning: The image depicted shows the resistance change when wiring multiple subwoofer terminals. Please refer to your subwoofer's owner's manual for the proper wiring of its terminals. Sonic Electronix, Inc. is not responsible for damage caused to your audio system or vehicle due to improper installation. Please call tech support at 1-877-289-7664 if you require additional assistance.

Product Name: NVX 12" X-Series Loaded Subwoofer Enclosure

  • NVX X-Series Car Audio Subwoofers
  • NVX X-Series Subwoofers | Sound Quality Sub in a Small Box
  • NVX XQW Subs
  • NVX X-Series 10" Subwoofer Bass Test | XQW104

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NVX 12" X-Series Loaded Subwoofer Enclosure

400W RMS, 12" X-Series Dual 4 ohm Car Subwoofer with Sealed Subwoofer Box


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NVX Speaker Wire (XWS1225)

25 ft. of True 12 Gauge EnvyFlex Speaker Cable/Wire (100% Oxygen-Free Copper)


NVX Sound Dampening Trunk Kit (SDTK20)

20 Square Feet of Sound Dampening Material (Five 18" x 32" Pieces)


Car Stereo and Speaker Installation Tool Kit

Complete Car Stereo Tool Kit, Includes Voltage Test Light, Wire Stripper and More



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