Subwoofer Cutout vs Bolt Circle: Getting the Mounting Hol...
A subwoofer's cutout diameter is the hole the cone drops through; the bolt circle is the ring the...
Read Article →Proline X
SKU: Pro 10-P VD10
One VD-10 in a front-firing box, vented at 35.0 Hz on a three-layer flush-mount baffle
The VD-10 is Skar's 10 inch at 42.0 Hz, a Qts of 0.47, 15.1 litres of Vas and 500 W RMS. This cabinet gives it 1.29 cubic feet net behind a 2.25 inch three-layer baffle, vented at 35.0 Hz through a 21.9 square inch slot beside the woofer, for an anechoic F3 of 30.5 Hz in a 30 by 14 by 12.0 inch front-firing box.
Threaded insert kit ships with this box. Skar Audio does not publish the mounting hole locations for the VD-10, so we cannot install the threaded inserts before it ships. The threaded insert kit comes in the box instead: inserts sized to the woofer, the correct drill bit, 2.5 inch allen-head screws, an allen key and woofer gasket tape. You set the inserts when you mount the woofer, and this box ships with one kit.
Sealed, the VD-10 needs 0.42 cubic feet net to reach a Qtc of 0.707. Vented, it trades that for deeper extension. The slot is gated at 600 W, 1.2 times Skar's rating: the channel runs 21.2 m/s and the mouth 12.5, and the cone peaks at 9.1 of its 11.5 mm with the subsonic filter in place. Skar's own ported recommendation is 1.25 cubic feet at 39 Hz, before driver and port displacement.
Three layers of 3/4 inch Langboard Elite make a 2.25 inch front. The outer layer is routed to the flange, so the woofer sits flush with the face; the two layers behind it carry the mounting hardware and the load.
A glossy black acrylic insert with the Skar Audio mark sits in the outer layer beside the woofer. It is standard on every Professional cabinet.
Threaded insert kit included, inserts NOT pre-installed: the manufacturer publishes no mounting hole locations, so the kit ships with the box for installation when the woofer goes in: 8 to 12 inserts sized to the woofer, the correct drill bit, 2.5 inch allen-head screws, allen key and gasket tape.
The 21.9 square inch slot beside the woofer is sized so the channel runs 21.2 metres per second and the mouth 12.5 metres per second at 1.2 times the driver's rating, under the 17 metres per second where a slot starts to chuff. The channel runs 6.50 inches along its wall and turns once along the back wall for another 17.57 inches, which is why a 35.0 Hz tuning fits a 12.00 inch deep box.
The VD-10 also builds in the Performance Optimized ported wedge and ported down-fire, the smaller and cheaper boxes. The Professional cabinet is the step up for it: a 2.25 inch three-layer baffle with the woofer flush in the outer layer, and a slot port gated at 600 W.
Every Professional cabinet is priced the same way, by its size: this one is 2.92 cubic feet outside. Delivery to the 48 states is inside the price; it ships as a 47 lb parcel and checkout adds nothing. The Performance Optimized 10 inch ported wedge is $369.99. The $33 difference is the larger box and the port this driver needs to run at its rating.
30.00" W x 14.00" H x 12.00" D external. Two windowed braces run front to back either side of the woofer, clearing the cutout by two and a half inches. The box ships dry: polyfill detunes a ported alignment. Inside the 30 by 14 Professional envelope for a single 10, 12.0 inches deep. 10.67 inch frame, flush in the outer baffle layer, 9.35 inch cutout, 4.50 inches of mounting depth. It ships as a parcel.
Skar publishes a full Thiele-Small table for the VD-10 on its product page, including a one-way Xmax of 11.5 mm. Some of it is softer than it looks. Skar gives no driver displacement anywhere, so 0.057 cubic feet is our estimate from comparable 10 inch woofers; it moves the tuning by a fraction of a hertz. Skar does not say how the Xmax was measured, so we size port and power against it rather than past it. Also: Skar leaves cone area blank on the VD, so the 326 square centimetres used here is derived from their Vas and compliance. Tuning includes a 1.5 Hz fold loss that is an estimate, not a bench measurement. Skar Audio does not publish the mounting hole locations for the VD-10, so we cannot install the threaded inserts before it ships. The threaded insert kit comes in the box instead: inserts sized to the woofer, the correct drill bit, 2.5 inch allen-head screws, an allen key and woofer gasket tape. You set the inserts when you mount the woofer, and this box ships with one kit.
Set a 28 Hz subsonic filter, 24 dB per octave. Below tuning the vent stops loading the cone; with the filter in place the cone reaches 9.1 mm of its 11.5 mm at 600 W.
| Series | Proline X Professional |
| Driver-Specific Fitment | Skar Audio VD-10 D2/D4 (Dual 2 Ohm or Dual 4 Ohm) |
| Enclosure Type | Ported | Front-Firing Standard Box |
| External Width | 30.00 Inches |
| External Height | 14.00 Inches |
| External Depth | 12.00 Inches |
| Internal Volume (Gross) | 1.86 Cubic Feet |
| Internal Volume (Net After Displacement) | 1.29 Cubic Feet |
| Port Type | Vertical Slot Beside The Woofer | Front Exit | One 90 Degree Bend Along The Back Wall |
| Port Geometry | 1.75 x 12.50 Inches, 21.9 Square Inches, 29.57 Inches Of Path |
| Port Area | 21.9 Square Inches |
| Port Tuning (Fb) | 35.0 Hz |
| Port Mouth | 1/2 In Roundover On All Four Edges, 37.1 Square Inches At The Face |
| Port Air Velocity | 21.2 m/s In The Channel, 12.5 m/s At The Mouth, At 600 W (17.0 m/s Chuff Threshold) |
| Design Power Basis | 600 W RMS (1.2 x The Driver Rating) For Port Velocity And Excursion |
| Predicted F3 | 30.5 Hz (Anechoic) |
| Passband Ripple | 1.06 dB (Anechoic) |
| Subsonic Filter | 28 Hz High-Pass, 24 dB/Octave - REQUIRED On A Vented Enclosure |
| Driver Fs | 42.00 Hz |
| Driver Qts | 0.470 |
| Driver Qes / Qms | 0.530 / 4.550 |
| Driver Vas | 15.100 Liters / 0.533 Cubic Feet |
| Driver Sd | 326.1 Square Centimeters |
| Driver BL | 15.80 |
| Driver Xmax | 12mm (One-Way) |
| Driver Displacement | 0.06 Cubic Feet (Published by Skar Audio) |
| Driver Sensitivity | 85.2 dB |
| Driver Power Handling | 500 Watts RMS |
| Driver Overall Diameter | 10.670 Inches (Skar Audio Spec) |
| Mounting Depth Required | 4.500 Inches (Skar Audio Spec) |
| Cutout Diameter | 9.350 Inches (Skar Audio Spec) |
| Flush Mount Recess | 11.625 Inches In The Outer Layer |
| Material | Langboard Elite 3/4" MDF |
| Construction | ShopSabre CNC / Two Windowed Braces Front To Back Either Side Of The Woofer |
| Joinery | Dado Joinery (CNC-Cut), Flat Panels |
| Front Baffle Construction | Three 3/4" MDF layers, 2.25" total | Woofer Flush-Mounted In The Outer Layer |
| Baffle Layers | 3 |
| Acrylic | Glossy Black Skar Audio Logo Insert, Outer Layer, Standard |
| Mounting Hardware | Threaded Insert Kit Included: 8-12 Inserts, Drill Bit, 2.5 In Allen-Head Screws, Allen Key, Gasket Tape |
| Voice Coil Configuration | Dual 2 Ohm |
| Terminal Cup | Proline X ABS/Carbon Fiber Composite | Back Panel, Terminal-Cup Side | 12g OFC Pre-Wired |
| Damping | None - Ships Dry. Polyfill Detunes A Ported Enclosure |
| Recommended Power | 350-500 Watts RMS (Skar Audio Rated: 500W RMS) |
| Carpet Finish | Plush Black |
| Shipping Weight | 53 lb |
| Shipping | UPS Ground Parcel, Included In The 48 States |
| Bundle Options | Enclosure Only (Bring Your Own Skar Audio VD-10) |
| Warranty | 2-Year Limited (Enclosure) |
| Manufactured | Tullahoma, Tennessee, USA |
Efficiency bandwidth product places the motor before anything else is decided.
1.29 cu ft net against a 15.1 L Vas, vented at 35.0 Hz.
This cabinet, 1.29 cu ft net vented at 35.0 Hz, against Skar Audio's recommended sealed box, 0.65 cu ft.
The same two boxes with cabin gain applied, 45 Hz corner, 18 dB ceiling.
Travel scales with the square root of power, so there is one wattage that puts the cone exactly on Skar's published 11.5 mm. The two traces are the same cabinet with the subsonic filter switched on and switched off.
| Driver | Skar Audio VD-10 |
| Coil Options | Dual 2 Ohm or Dual 4 Ohm |
| Voice Coil Diameter | 2.00 in |
| Coil Wire | Copper (Pure Copper), 4 layer |
| Cone | Competition Grade Pressed Paper Cone |
| Surround | Stitched High Roll Foam Surround |
| Motor | Single slug magnet, 6.00 in diameter |
| Power, RMS | 500 W |
| Power, Peak | 800 W |
| Sensitivity | 85.2 dB, reference condition not stated by Skar Audio |
| Mounting Depth | 4.50 in |
| Cutout Diameter | 9.35 in |
| Frame Outside Diameter | 10.67 in |
Every Proline X Professional Series enclosure is CNC-cut from Langboard Elite MDF, 3/4" (18mm) panels produced to published mill specifications. Most enclosure manufacturers source generic MDF without published data. We can tell you the internal bond rating, the modulus of elasticity, the modulus of rupture, and the face and edge screw holding strength for every panel in this enclosure, because we chose the material based on those numbers, not on price or availability.
Langboard Elite is produced in the United States. The specifications below are pulled directly from Langboard's published mill data and are verifiable. This is the same panel stock used in our full Proline X lineup.
| Property | Value | Why It Matters |
|---|---|---|
| Panel Stock | Langboard Elite MDF | Named, verifiable panel source, not generic "high-density MDF" |
| Thickness | 3/4" (18mm) | Industry standard for subwoofer enclosures; panels below this flex under pressure |
| Density | 48.5 lbs/ft³ | Higher density = less porosity, better screw retention, reduced resonance |
| Internal Bond | 200 psi | Measures resistance to delamination under sustained internal pressure. The most enclosure-relevant spec on this sheet |
| Modulus of Rupture (MOR) | 4,200 psi | Bending strength before the panel breaks, relevant for larger unsupported baffle spans |
| Modulus of Elasticity (MOE) | 410,000 psi | Stiffness under load; higher MOE means less panel flex under bass pressure, less resonance |
| Face Screw Holding | 325 lbs | How firmly the panel surface holds a screw; critical for baffle joint integrity over time |
| Edge Screw Holding | 250 lbs | Panel edge retention, relevant for every joint that isn't face-to-face |
The internal bond rating measures how well the MDF panel resists delamination under sustained pressure applied perpendicular to the face. In a subwoofer enclosure, every bass transient generates a pressure pulse that pushes outward on every panel simultaneously. A panel that begins to delaminate internally loses stiffness gradually. The symptoms are slow: a box that starts to sound softer, less defined, less punchy over months of use. 200 psi internal bond is the spec that determines how long this enclosure holds its acoustic integrity under daily use at real power levels.
The modulus of elasticity measures panel stiffness, its resistance to bending under load. A stiffer panel flexes less under the pressure generated by a high-excursion driver at volume. Panel flex is a source of acoustic coloration: the panel itself begins to radiate sound at its own resonant frequency, adding distortion to the output. 410,000 psi stiffness combined with V-groove and dado joinery means the panels stay rigid and the bracing controls resonance at the structure level, not the panel level. The bass you hear comes from the driver, not the box.
Screw holding strength determines how firmly the panel grips a fastener at the face and at the edge. This matters most at the baffle joint, where the front panel meets the side panels and where the driver is mounted. A panel with low screw holding strength allows fasteners to loosen over time under vibration, leading to air gaps at the joint and loss of acoustic seal. 325 lb face screw holding strength means the baffle hardware stays put. Combined with dado joinery and adhesive, the front panel on a Proline X Professional Series enclosure is not going anywhere.
The phrase "premium MDF" or "high-density MDF" appears on marketing copy for enclosures across every price point, from $40 to $400. It is not a specification. It is a description with no defined standard. Langboard Elite is a named, sourced, mill-documented product with published data. We name it in our copy because naming it holds us accountable to the spec. You can look up Langboard Elite independently, verify the numbers on this page, and confirm you are getting what we say you are getting. That is the point.
Most enclosures are built to a price point. Proline X is built to a spec. Every box starts with published-data MDF, gets CNC-cut to exact internal volume, and is assembled by hand in our Tennessee facility. The difference shows up in the measurements, and in how the box holds up two years into daily use.
Panels are machine-cut on ShopSabre CNC routers and joined with V-groove and dado joinery. Consistent geometry, no hand-cut variance, no gaps at the joints.
Hand-assembled at our facility in Tullahoma, TN. Every enclosure is inspected before it ships.
Internal volume and port geometry are calculated to spec and CNC-cut to exact dimensions. The box performs the same way every time.








