

Performance Optimized · Datasheet
Performance Optimized Down Fire Wide Sealed 12" Enclosure NVX VSW12v3 · Single 12" Sealed enclosure
- Net volume
- 1.606 cu ft after the brace and 0.09 cu ft displacement
- External dimensions
- 41 in W × 8.375 in in the down fire position H × 14 in D
- Front baffle
- 1.5 in double baffle, outer layer machined as a flush recess
- Alignment: 1.606 cu ft net. VSW122v3 (D2): Qtc 0.696, Fc 46.0 Hz, F3 46.8 Hz; VSW124v3 (D4): Qtc 0.717, Fc 47.5 Hz, F3 46.8 Hz
- Down Fire Wide: 41"W x 14"D x 8.375"H in down fire position, excludes standoffs, square corners
- Versus the standard 30 x 15: 10.17 in tall and 1.60 cu ft net there, 8.375 in tall and 1.606 cu ft net here
- Driver: NVX VSW12v3 (VSW122v3 D2 or VSW124v3 D4), 600 W RMS, 13.5 mm Xmax, 6.45 in mounting depth
- Standoffs: Included, 1.75 in, shipped uninstalled. Installed height 10.125 in
Spec of record
Technical specifications
| Specification | Value |
|---|---|
| Series | Proline X Performance Optimized Down Fire Wide |
| Compatible Driver | NVX VSW12v3. Direct fit |
| Enclosure Type | Sealed, down fire, floor coupled |
| Intended Fitment | Spaces where height or depth is the limit and 41 in of run is available |
| Chamber Configuration | Single chamber, windowed U-brace, one side-mounted terminal cup |
| External Width | 41 in |
| External Depth | 14 in |
| External Height | 8.375 in in the down fire position, excludes standoffs |
| Installed Height | 10.125 in including the 1.75 in standoffs |
| Internal Volume, Gross | 1.71 cu ft |
| Internal Volume, Net | 1.606 cu ft after the brace and 0.09 cu ft displacement |
| Height Set By | Airspace; 1.175 in clearance above the motor |
| Alignment, VSW122v3 (D2) | Qtc 0.696, Fc 46.0 Hz, F3 46.8 Hz anechoic |
| Alignment, VSW124v3 (D4) | Qtc 0.717, Fc 47.5 Hz, F3 46.8 Hz anechoic |
| Comparison, Standard 30 x 15 | 10.17 in tall, 1.60 cu ft net. Wide format is 8.375 in tall with 1.606 cu ft net |
| Woofer Opening | 11.22 in, NVX's published cutout |
| Frame Outer Diameter | 12.44 in, NVX published |
| Bolt Circle | 11.73 in, NVX published; threaded inserts pre-installed |
| Driver Displacement | 0.090 cu ft, NVX published |
| VSW122v3 (D2) Fs / Qts / Qes / Qms / Vas | 36.62 Hz / 0.554 / 0.622 / 5.06 / 26.23 L |
| VSW124v3 (D4) Fs / Qts / Qes / Qms / Vas | 37.35 Hz / 0.564 / 0.635 / 5.05 / 28.04 L |
| Driver Sd | 511 cm2, published by NVX |
| Xmax | 13.5 mm one way, NVX spec |
| Driver Power Handling | 600 W RMS, NVX spec |
| Floor Slot | 0.78 times the cone area at the 1.75 in standoff |
| Parameter Source | NVX VSW122v3 / VSW124v3 owner's manual and nvx.com product pages |
| Material | Langboard Elite 3/4 in MDF |
| Construction | ShopSabre CNC, V-groove and dado joinery |
| Panel Thickness | 0.75 in |
| Front Baffle | 1.5 in double baffle, outer layer machined as a flush recess |
| Internal Bracing | Windowed U-brace, dadoed to the shell |
| Corner Profile | Square, Down Fire series standard |
| Driver Mounting | Threaded inserts pressed on NVX's published 11.73 inch bolt circle, stainless machine screws included |
| Terminal Cup | One Proline X ABS and carbon fiber composite, side mounted, pre-wired 12 gauge OFC |
| Standoffs | Included, 1.75 in, shipped uninstalled |
| Damping | Light polyfill wall lining, does not alter acoustic volume |
| Carpet | Plush Black |
| Bundle Options | Enclosure only, bring your own NVX VSW12v3 |
| Warranty | 1 Year Limited |
| Built In | Tullahoma, Tennessee |
Modelled response
Performance in this enclosure
01Is it a sealed driver?
Efficiency bandwidth product places the motor before anything else is decided.
02What the box does to it
1.606 cu ft against a 26.2 L Vas.
03The watts that reach Xmax (in this enclosure)
Travel scales with the square root of power, so there is one wattage that puts the cone exactly on 13.5 mm — and a bigger one once a subsonic filter stops it wasting travel below the passband.
| Param | Value | Unit | Note |
|---|---|---|---|
| Fs | 36.62 / 37.35 | Hz | free-air resonance |
| Qts | 0.554 / 0.564 | D2 / D4 | |
| Vas | 26.23 / 28.04 | L | equivalent compliance |
| Sd | 510.6 | cm² | effective piston area |
| Xmax | 13.5 | mm | one-way linear travel |
| Pe | 600 | W | continuous RMS |
| SPL | 85.0 | dB | 1 W / 1 m, derived from T/S |
Driver parameters as published by NVX VSW12v3 owner’s manual. Curves computed against this enclosure’s actual net airspace.
From the shop floor
Installer's take
Same VSW12v3 as the standard 30 by 15 box, laid out 41 by 14. One inch shallower, 11 inches longer, and 8.375 inches tall against 10.17. Measure all three dimensions before choosing between them.
Airspace set the height here, 1.606 cubic feet net, with 1.175 inches clear above the motor.
Alignment: VSW122v3 (D2) at Qtc 0.696, F3 46.8 Hz; VSW124v3 (D4) at Qtc 0.717, F3 46.8 Hz.
Cut is 11.22, NVX's own figure, and the inserts are already pressed on their 11.73 bolt circle. Floor slot is 0.78 times the cone area at the 1.75 standoff. Leave the polyfill as it is and run it at 600 watts or under.
Before you order
Questions
Why is this cabinet 41 inches wide instead of 30?
Because it trades length for depth and height. The standard single Down Fire platform is 30 wide by 15 deep; this one is 14 deep, 1 inch shallower, and runs 41 inches long to put the airspace along the length instead.
That lets it stand 8.375 inches tall against 10.17 for the standard box. A 12 inch frame needs about 13 inches of baffle, so 14 is as shallow as a 12 can go. If you have 41 inches of run and height or depth is your limit, this is the shape that works.
How does this compare to the standard 30 x 15 VSW12v3 enclosure?
The standard box is 30 by 15 by 10.17 inches and holds 1.60 cubic feet net. This one is 41 by 14 by 8.375 inches and holds 1.606 cubic feet net.
Choose the standard box when length is limited. Choose this one when height or depth is the limit and you have 41 inches of run.
What alignment does this enclosure produce?
At 1.606 cubic feet net the result is VSW122v3 (D2): Qtc 0.696, Fc 46.0 Hz, F3 46.8 Hz; VSW124v3 (D4): Qtc 0.717, Fc 47.5 Hz, F3 46.8 Hz, calculated from the driver's own published Thiele-Small parameters.
That is a little under the 0.707 maximally flat reference, so the rolloff is gentle rather than peaked. The figures are anechoic; in a car, cabin gain adds real output below 50 Hz, so in-vehicle response runs deeper.
How much power should I run, and how do I wire it?
NVX rates the VSW12v3 at 600 watts RMS. The VSW122v3 (D2) wires to 4 ohms with its coils in series or 1 ohm in parallel. The VSW124v3 (D4) wires to 8 ohms in series or 2 ohms in parallel. Anything under 1 ohm, and many amplifiers at 1 ohm, is outside what the amplifier is built for; series wiring is the safe default. Confirm the load against your amplifier's minimum stable impedance before powering the system.
How tall is this once the standoffs are on?
The cabinet is 8.375 inches tall measured in the down fire position, excluding standoffs. The standoffs hold 1.75 inches under the baffle, so plan your space around 10.125 inches installed.
The standoffs ship uninstalled, so you can place them to suit your floor, or leave them off and run the cabinet front firing or up firing.
Where is the terminal cup located on a down fire enclosure?
Side mounted. Every Proline X Performance Optimized enclosure uses a side mounted terminal cup regardless of alignment, whether standard, wedge, or down fire. On this cabinet that keeps the connection accessible with the enclosure installed, since the baffle faces the floor. The cup is our Proline X ABS and carbon fiber composite unit with stainless hardware, copper ring terminals, and pre-wired 12 gauge OFC.
How is this enclosure built?
V-groove and dado joinery, CNC cut on ShopSabre routers from Langboard Elite MDF, with square corners as the Down Fire standard. Every panel joint is a machined interlocking groove that locks before adhesive is applied, which keeps the cabinet airtight under sustained pressure cycling.
The 1.5 inch double baffle has its outer layer machined as a flush recess so the driver bolts to the inner layer, and a windowed U-brace stiffens the long panels. Polyfill is installed as a light wall lining; do not add more, since packing a sealed box makes it act larger and moves the alignment. Assembled and inspected in Tullahoma, Tennessee.
Is the NVX VSW12v3 included with this enclosure?
No. This listing is for the enclosure only. Bring your own NVX VSW12v3. The cutout and cabinet height are cut direct fit for this driver. Threaded inserts are pressed on NVX's published 11.73 inch bolt circle and stainless machine screws are included.
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