

Performance Optimized · Datasheet
Performance Optimized Down Fire Wide Sealed Dual 12" Enclosure NVX VCW12v3 · Dual 12" Sealed enclosure
- Net volume
- 0.857 cu ft after displacement
- External dimensions
- 41 in W × 9.625 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: 0.857 cu ft net per chamber, 1.714 cu ft total. VCW122v3 (D2): Qtc 0.665, Fc 41.7 Hz, F3 44.4 Hz; VCW124v3 (D4): Qtc 0.665, Fc 41.7 Hz, F3 44.4 Hz per driver
- Down Fire Wide: 41"W x 14"D x 9.625"H in down fire position, excludes standoffs, square corners
- Versus the standard 30 x 15: 11.82 in tall and 0.85 cu ft net per chamber there, 9.625 in tall and 0.857 cu ft net here
- Chambers: Two fully separate sealed chambers, 3/4" MDF full divider, one shared side-mounted terminal cup
- Drivers: Pair of NVX VCW12v3 (VCW122v3 D2 or VCW124v3 D4), 1200 W RMS each, 23 mm Xmax, 6.85 in mounting depth
- Standoffs: Included, 1.75 in, shipped uninstalled. Installed height 11.375 in
Spec of record
Technical specifications
| Specification | Value |
|---|---|
| Series | Proline X Performance Optimized Down Fire Wide |
| Compatible Driver | NVX VCW12v3, pair required. Direct fit |
| Enclosure Type | Sealed, dual driver, down fire, floor coupled |
| Intended Fitment | Spaces where height or depth is the limit and 41 in of run is available |
| Chamber Configuration | Two fully separate chambers, full divider, single shared side-mounted terminal cup |
| External Width | 41 in |
| External Depth | 14 in |
| External Height | 9.625 in in the down fire position, excludes standoffs |
| Installed Height | 11.375 in including the 1.75 in standoffs |
| Internal Volume, Gross | 2.05 cu ft total |
| Per-Chamber Net Volume | 0.857 cu ft after displacement |
| Total Net Volume | 1.714 cu ft |
| Height Set By | Airspace; 2.025 in clearance above the motor |
| Alignment, VCW122v3 (D2) per chamber | Qtc 0.665, Fc 41.7 Hz, F3 44.4 Hz anechoic |
| Alignment, VCW124v3 (D4) per chamber | Qtc 0.665, Fc 41.7 Hz, F3 44.4 Hz anechoic |
| Comparison, Standard 30 x 15 | 11.82 in tall, 0.85 cu ft net per chamber. Wide format is 9.625 in tall with 0.857 cu ft net per chamber |
| Woofer Opening | 11.18 in, two, NVX's published cutout |
| Frame Outer Diameter | 12.64 in, NVX published |
| Bolt Circle | 11.63 in, NVX published; threaded inserts pre-installed |
| Driver Displacement | 0.150 cu ft, NVX published |
| VCW122v3 (D2) Fs / Qts / Qes / Qms / Vas | 25.05 Hz / 0.400 / 0.434 / 5.12 / 42.90 L |
| VCW124v3 (D4) Fs / Qts / Qes / Qms / Vas | 25.05 Hz / 0.400 / 0.434 / 5.12 / 42.90 L (NVX product page column) |
| Driver Sd | 530 cm2, published by NVX |
| Xmax | 23 mm one way, NVX spec |
| Driver Power Handling | 1200 W RMS per driver, NVX spec |
| Floor Slot | 0.75 times the cone area at the 1.75 in standoff |
| Parameter Source | NVX VCW122v3 / VCW124v3 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 | Full-height 3/4 in bonded divider |
| Corner Profile | Square, Down Fire series standard |
| Driver Mounting | Threaded inserts pressed on NVX's published 11.63 inch bolt circle, stainless machine screws included |
| Terminal Cup | One Proline X ABS and carbon fiber composite, side mounted, pre-wired 12 gauge OFC to both driver positions in parallel |
| Standoffs | Included, 1.75 in, shipped uninstalled |
| Damping | Light polyfill wall lining in both chambers, does not alter acoustic volume |
| Carpet | Plush Black |
| Bundle Options | Enclosure only, bring your own pair of NVX VCW12v3 |
| 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
0.857 cu ft against a 42.9 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 23.0 mm — and a bigger one once a subsonic filter stops it wasting travel below the passband.
| Param | Value | Unit | Note |
|---|---|---|---|
| Fs | 25.05 | Hz | free-air resonance |
| Qts | 0.400 / 0.400 | D2 / D4 | |
| Vas | 42.90 / 42.90 | L | equivalent compliance |
| Sd | 530.0 | cm² | effective piston area |
| Xmax | 23 | mm | one-way linear travel |
| Pe | 1200 | W | continuous RMS |
| SPL | 83.8 | dB | 1 W / 1 m, derived from T/S |
Driver parameters as published by NVX VCW12v3 owner’s manual. Curves computed against this enclosure’s actual net airspace.
From the shop floor
Installer's take
Same pair of VCW12v3 as the standard 30 by 15 box, laid out 41 by 14. One inch shallower, 11 inches longer, and 9.625 inches tall against 11.82. Measure all three dimensions before choosing between them.
Airspace set the height here, 0.857 cubic feet net per chamber, with 2.025 inches clear above the motor.
Alignment: VCW122v3 (D2) at Qtc 0.665, F3 44.4 Hz; VCW124v3 (D4) at Qtc 0.665, F3 44.4 Hz.
Cut is 11.18, NVX's own figure, and the inserts are already pressed on their 11.63 bolt circle. Floor slot is 0.75 times the cone area at the 1.75 standoff; taller feet help if the floor allows. Leave the polyfill as it is and run it at 1200 watts per driver 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 dual 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 9.625 inches tall against 11.82 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 dual VCW12v3 enclosure?
The standard box is 30 by 15 by 11.82 inches and holds 0.85 cubic feet net per chamber. This one is 41 by 14 by 9.625 inches and holds 0.857 cubic feet net per chamber.
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 0.857 cubic feet net per chamber the result is VCW122v3 (D2): Qtc 0.665, Fc 41.7 Hz, F3 44.4 Hz; VCW124v3 (D4): Qtc 0.665, Fc 41.7 Hz, F3 44.4 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 these subwoofers?
NVX rates the VCW12v3 at 1200 watts RMS, 2400 watts RMS combined. A pair of VCW122v3 (D2) drivers can land on 0.5 ohm with all four coils in parallel, 2 ohms as series pairs in parallel, or 8 ohms all in series. A pair of VCW124v3 (D4) drivers can land on 1 ohm with all four coils in parallel, 4 ohms as series pairs in parallel, or 16 ohms all in series. 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 9.625 inches tall measured in the down fire position, excluding standoffs. The standoffs hold 1.75 inches under the baffle, so plan your space around 11.375 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, and there is one cup serving both chambers. 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 baffles face 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 full-height bonded 3/4 inch divider separates the chambers and ties the walls together across the 41 inch span. 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 pair of NVX VCW12v3 included with this enclosure?
No. This listing is for the enclosure only. Bring your own pair of NVX VCW12v3. The cutout and cabinet height are cut direct fit for both positions. Threaded inserts are pressed on NVX's published 11.63 inch bolt circle and stainless machine screws are included.
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