Proline X
Performance Optimized Wedge Ported Dual 10" Enclosure | Ground Zero GZRW 250-D2 FLAT
SKU: PO 10D-P W GZRW250F BB
- Alignment: 1.63 cu ft net shared, vented at 32.5 Hz, F3 34.1 Hz
- Drivers: Pair of Ground Zero GZRW 250-D2 FLAT, 400 W RMS each, dual 2 ohm
- Port: Triangular side slot, 21.4 sq in
- Cabinet: 32.00" W x 15" H x 9.50/14.96" D
Financing available. Choose Shop Pay Installments at checkout.
Performance Optimized Wedge Ported Dual 10" Enclosure | Ground Zero GZRW 250-D2 FLAT
More enclosures cut for Ground Zero subwoofers: Ground Zero Subwoofer Boxes
Proline X Performance Optimized Wedge Dual 10" Ported
Two GZRW 250-D2 FLATs vented at 32.5 Hz in one trunk wedge, 1.63 cubic feet and a 34.1 Hz F3
Why this pair is vented at 32.5 Hz
This cabinet gives the pair 1.63 cubic feet in one shared chamber, 0.82 per driver, vented at 32.5 Hz through a 21.4 square inch triangular port, and reaches 34.1 Hz anechoic. Ground Zero's own vented recommendation for one GZRW 250-D2 FLAT is 0.71 cubic feet net with a single 7 cm round port, F3 37 Hz; each driver gets a little more air than that here, in a 32 by 15 inch dual wedge, with a far larger port. The port runs 20.6 m/s in the channel and 13.2 at the flared mouth with both drivers at 400 watts, and each cone peaks at 7.5 of its 22 mm. Passband ripple is 2.2 dB. Our sealed dual wedge (PO 10D-S W GZRW250F) holds 1.00 cubic feet per chamber at Qtc 0.81 with half power at 37 Hz; this ported box reaches deeper.
Ground Zero's GZRW 250-D2 FLAT table holds together on Qts and on its motor figures, but prints no cone area: the 350 square centimeters used here is derived from their Vas, Fs and moving mass. Displacement is our 0.038 cubic foot estimate per driver, and tuning carries a 1.5 Hz fold loss that is an estimate, not a bench measurement.
Two drivers, one chamber, one port
A ported dual shares its air: one chamber and one port tuned for the pair, so the two cones load the same volume and the port carries both. That is the opposite of our sealed duals, which split the chambers. Windowed braces stiffen the 32 inch panels; their windows keep the cavity one chamber and leave each motor clear.
Trunk-load wedge, explained
The cabinet is 32.00 inches wide and 15 tall, 9.50 inches deep at the top and 14.96 at the base. The back rakes 20 degrees to sit against the rear seat; the baffle stays vertical, so the drivers fire rearward into the trunk.
The port is the product
The port is a triangular slot formed by the floor, the back panel and one bevelled panel seated in dados, running 25.9 inches along the back and exiting through the side with a 0.5 inch roundover on all three edges of the mouth. Its 21.4 square inches carry both drivers.
Run a subsonic filter
Below tuning the port stops loading the cones and excursion climbs fast. Set a subsonic filter near 26 Hz and leave it there.
Cut for this driver, not for a catalogue
Both baffle openings are CNC cut to 9.13 in under 10.87 in recesses, centred 8.625 and 23.375 in from the mouth-side edge. The 3.35 in motors clear the port panel with 3.84 in to spare. Ground Zero prints no bolt circle, so the baffle ships undrilled with a threaded insert kit and stainless machine screws: set each driver in its recess, mark its holes, drill and press the inserts. Cut from Langboard Elite 3/4 inch MDF with V-groove and dado joinery and a 1.5 inch double baffle.
Power, wiring and warranty
Ground Zero rates the GZRW 250-D2 FLAT at 400 watts RMS per driver, 800 across the pair; aim for 280 to 400 per driver. Each GZRW 250-D2 FLAT has two 2 ohm coils: a pair lands on 2 ohms with each woofer's coils in series and the two woofers in parallel, or 8 ohms all in series. 0.5 ohm, everything in parallel, is outside what most amplifiers are built for. It ships dry: do not add polyfill to a ported box. 1 year limited warranty. Enclosure only, the drivers are purchased separately. Call or text 931-563-5151.
| Series | Proline X Performance Optimized Ported Wedge |
| Compatible Driver | Ground Zero GZRW 250-D2 FLAT (dual 2 ohm), quantity 2. Direct fit |
| External Dimensions | 32.00" W x 15" H, 14.96" D at the base tapering to 9.50" at the top |
| Internal Volume, Net | 1.63 cu ft, one shared chamber (0.82 per driver) |
| Tuning | 32.5 Hz |
| Port | Triangular side slot, 21.4 sq in, 25.9 in path |
| Alignment | F3 34.1 Hz anechoic, ripple 2.2 dB |
| Driver Openings | 9.13 in cutout, 10.87 in recess, x2 at 8.625 / 23.375 in |
| Driver Mounting | Threaded insert kit included, NOT pre-installed: Ground Zero prints no bolt circle |
| Driver Displacement | 0.038 cu ft each, estimated; Ground Zero publishes none |
| Parameter Source | Ground Zero GZRW 250-D2 FLAT owner's manual; cone area derived |
| Motor Clearance | 3.84 in to the port panel |
| Bracing | 2 windowed C braces |
| Material | Langboard Elite MDF, V-groove and dado joinery |
| Front Baffle | 1.5 in double baffle |
| Terminal Cup | One, side mounted, pre wired 12 gauge OFC to both drivers |
| Acrylic Insert | Gloss black acrylic baffle insert standard; None variant minus $20 |
| Damping | None, ships dry |
| Carpet | Plush black |
| Shipping Weight | 58 lb |
| Warranty | 1 Year Limited |
| Built In | Tullahoma, Tennessee |
01Is this driver right for a ported box?
Efficiency bandwidth product places the motor before anything else is decided.
02What the box does to it
1.63 cu ft net against a 71.6 L Vas, vented at 32.5 Hz.
03Ported vs Sealed
No sealed comparison is shown for this driver.
04The watts that reach Xmax (in this enclosure)
Travel scales with the square root of power, so there is one wattage that puts both cones exactly on Ground Zero's published 22.0 mm. The two traces are the same cabinet with the subsonic filter switched on and switched off. Every power figure in this section is for the pair, split evenly.
Built From a Spec Sheet, Not a Sales Sheet
Every Proline X Performance 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.
Langboard Elite MDF: Published Mill Data
| 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 |
200 psi: The Number That Actually Matters for Enclosures
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.
410,000 psi MOE: Less Flex, Less Resonance
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.
325 lb Face / 250 lb Edge: Joints That Stay Locked
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 Performance Series enclosure is not going anywhere.
Named Panel Stock: Not "Premium MDF"
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.
Why Proline X?
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.
CNC-Cut to Spec
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.
Handcrafted in USA
Hand-assembled at our facility in Tullahoma, TN. Every enclosure is inspected before it ships.
Tuned to the Build
Internal volume and port geometry are calculated to spec and CNC-cut to exact dimensions. The box performs the same way every time.
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