

Performance Optimized · Datasheet
Performance Optimized Wedge Sealed 12" Enclosure Skar Audio VD-12 · Single 12" Sealed enclosure
- Net volume
- 1.00 cu ft after the brace and an estimated 0.085 cu ft displacement
- Max mounting depth
- 4.95 in required; 0.75 in clearance above the motor against the raked rear panel
- External dimensions
- 25.41 in W × 15 in at the seat face H × 11.85 in at the base D
- Front baffle
- 1.5 in double baffle, outer layer machined as a flush recess
- Best For: Skar Audio VD-12 Trunk-Fit Builds
- Net Volume: 1.00 cu ft (1.10 cu ft Gross)
- Driver Match: Skar Audio VD-12 (D2)
- Construction: Rear-Firing Wedge | V-Groove/Dado | Double 1.5" Baffle | Threaded Insert Kit
Spec of record
Technical specifications
| Specification | Value |
|---|---|
| Series | Proline X Performance Optimized Wedge |
| Compatible Driver | Skar Audio VD-12 D2, quantity 1. Direct fit |
| Configuration | Single 12 inch, single chamber sealed wedge |
| Mounting Position | Trunk or cargo area, tall face against the rear seat back |
| Firing Direction | Rearward into the trunk. Not a down fire design, no feet included |
| External Width | 25.41 in |
| External Height | 15 in at the seat face |
| External Depth | 11.85 in at the base, tapering to 6.39 in at the top |
| Internal Volume, Gross | 1.10 cu ft |
| Internal Volume, Net Acoustic | 1.00 cu ft after the brace and an estimated 0.085 cu ft displacement |
| Driver Mounting Depth | 4.95 in required; 0.75 in clearance above the motor against the raked rear panel |
| Alignment, D2 | Qtc 0.876, fc 56.2 Hz, F3 47.4 Hz anechoic |
| Skar Recommended Sealed | 1 cu ft, net of driver, bracing and port (Qtc 0.88 D2) |
| Woofer Opening | 11.28 in, Skar's published cutout |
| Frame Outer Diameter | 12.60 in |
| Bolt Circle | Not printed by Skar; threaded insert kit included |
| Driver Displacement | 0.085 cu ft, estimated; Skar publishes none |
| D2 Fs / Qts / Qes / Qms / Vas | 35.3 Hz / 0.55 / 0.62 / 4.42 / 43.5 L |
| Driver Sd | 505 cm2, derived from Vas and Cms; Skar leaves it blank |
| Xmax | 11 mm one way, Skar spec |
| Driver Power Handling | 500 W RMS, Skar spec |
| Wiring Options | The VD-12 D2 wires to 4 ohms with its coils in series or 1 ohm 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. |
| Parameter Source | skaraudio.com VD-12 product page, T/S Parameters and Subwoofer Measurements |
| Material | Langboard Elite MDF |
| Construction | CNC cut, 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 brace, dadoed to the shell |
| Driver Mounting | Threaded insert kit included, NOT pre-installed: Skar prints no bolt circle |
| Terminal Cups | One Proline X ABS and carbon fiber composite, side mounted, pre wired 12 gauge OFC |
| Acrylic Insert | Gloss black acrylic baffle insert standard |
| Damping | Light polyfill wall lining, does not alter acoustic volume |
| Carpet | Plush black |
| Shipping Weight | 40 lb |
| 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
1.00 cu ft against a 43.5 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 11.0 mm, and in this alignment a subsonic filter barely moves it.
| Param | Value | Unit | Note |
|---|---|---|---|
| Fs | 35.30 | Hz | free-air resonance |
| Qts | 0.550 | dual 2 ohm | |
| Vas | 43.50 | L | equivalent compliance |
| Sd | 505.3 | cm² | effective piston area |
| Xmax | 11 | mm | one-way linear travel |
| Pe | 500 | W | continuous RMS |
| SPL | 86.7 | dB | 1 W / 1 m, derived from T/S |
Driver parameters as published by Skar Audio VD-12 product page. Curves computed against this enclosure’s actual net airspace.
From the shop floor
Installer's take
1.00 cubic feet, Qtc 0.876 on the D2. This box is for the VD-12 D2. The D4's higher Qts reads Qtc 0.96 in the same 1.00 cubic feet, boomy rather than tight, so we do not recommend it here.
The 4.95 inch motor clears the raked back with 0.75 to spare; the volume, not the motor, sets the rest of the cabinet.
Cut is 11.28, Skar's own figure. Inserts ship in the kit, not pressed: Skar prints no bolt circle. Mark from the driver, drill, press. It is sealed, so leave the polyfill as it is and run it at 500 watts or under.
Before you order
Questions
Does this fit the Skar VD-12, and will any other 12 inch fit?
The VD-12 D2, yes. The baffle is cut to 11.28 in, Skar's published cutout, under the 12.60 in frame. The 4.95 inch motor clears the cabinet with 0.75 inch to spare. This box is for the VD-12 D2. The D4's higher Qts reads Qtc 0.96 in the same 1.00 cubic feet, boomy rather than tight, so we do not recommend it here.
Any other 12, no. The airspace is worked out from the VD-12's own Qts and Vas, and a different woofer that happened to drop into the hole would not see the alignment printed on this page.
Why 1.00 cubic feet, and what alignment does it target?
1.00 cubic feet is the volume this cabinet is built to on the D2 figures (Fs 35.3 Hz, Qts 0.55, Vas 43.5 liters): Qtc 0.876, half power at 47.4 Hz. This box is for the VD-12 D2. The D4's higher Qts reads Qtc 0.96 in the same 1.00 cubic feet, boomy rather than tight, so we do not recommend it here.
That is Skar's own recommended sealed volume for the VD-12. It reads Qtc 0.88 on the D2, above the 0.707 of a maximally flat alignment, so expect a mild lift near 56 Hz rather than a flat rolloff. Skar's numbers are the only published source for this driver, so treat the Qtc as good to a few hundredths.
What amplifier power should I run, and how should I wire it?
Skar rates the VD-12 at 500 watts RMS, so target 350 to 500 watts RMS at the final load.
The VD-12 D2 wires to 4 ohms with its coils in series or 1 ohm 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 your amplifier's minimum stable impedance first.
Why the wedge angle, and why rear-firing into the trunk?
The seat-side face carries a 20 degree rake that matches the lean of a factory rear seat back, so the cabinet sits flush against it and the cargo space in front stays usable. The baffle is the vertical trunk-lid-side face, so the driver fires rearward into the trunk cavity.
The trunk acts as an acoustic extension for the sealed box, and the cabin adds real output below 50 Hz, so in-vehicle response runs deeper than the anechoic 47.4 Hz on this page.
Why is the front baffle double-layered?
The baffle is two bonded 3/4 inch sheets, 1.5 inches through. A single 3/4 inch panel flexes under the pressure a 12 inch woofer puts on it at 500 watts, which smears output and works the driver loose over time; the second layer stiffens the face and gives the mounting hardware twice the material to bite.
The outer layer is machined as a flush recess to the 12.60 inch frame, so the driver bolts to the inner layer and sits flush with the gloss black acrylic insert.
What is the expected low-frequency extension?
Anechoic F3 is 47.4 Hz on the D2, with system resonance at 56.2 Hz. Above Qtc 0.707 the response carries a small bump before the rolloff and F3 sits below fc.
Those figures exclude cabin gain. In a car the cabin's transfer function adds real output below 50 Hz, so in-vehicle response runs deeper than the numbers above.
Do I need to add polyfill or damping?
No. Polyfill is already installed as a light wall lining to control internal reflections, and the quantity is chosen so it does not change the acoustic volume.
Do not add more. Packing a sealed box with fill makes it behave as though it were larger, which walks the alignment away from the 1.00 cubic feet this cabinet was built to.
Is the driver included, and are the threaded inserts installed?
No driver. This is an enclosure only. You receive the cabinet finished in plush black carpet with the gloss black acrylic baffle insert, one side-mounted pre-wired terminal cup, the polyfill lining already in place, and a threaded insert kit with stainless machine screws.
The inserts ship loose on purpose: Skar prints no bolt circle for the VD-12, so you set the driver in the recess, mark its holes, drill and press the inserts. The Skar VD-12 is purchased separately, and the cabinet is cut direct fit to it, not a general purpose 12 inch box.
Same series, same size
Alpine R2-W12
Alpine R2-W12
Alpine RSW12
Alpine RSW12
Alpine S2-W12
Arc Audio 10" Arc Series
Arc Audio ARC 12