Proline X
Performance Optimized Down Fire Wide Sealed 10" Shallow Sub Enclosure | ResoNix GUS-10
SKU: PO 10-S DFW GUS
- Alignment: 0.723 cu ft net. Qtc 0.648, Fc 36.2 Hz, F3 39.7 Hz (Dual 4-Ohm); Qtc 0.568, Fc 34.0 Hz, F3 44.3 Hz (Dual 2-Ohm)
- Height: Set by the 3.996 in mounting depth, not a volume target: more air than the standard box, lower Qtc
- Driver: ResoNix GUS-10 D2 or D4, 500W RMS, 18mm Xmax, vented rear cone, pole vent may be fully blocked
- Standoffs: Included, ResoNix specifies 55mm from baffle surface to the floor
- Cabinet: 41"W x 12"D x 5.5"H in down fire position, excludes standoffs, square corners
Financing available. Choose Shop Pay Installments at checkout.
Performance Optimized Down Fire Wide Sealed 10" Shallow Sub Enclosure | ResoNix GUS-10
More enclosures cut for ResoNix subwoofers: ResoNix Subwoofer Boxes
Proline X Performance Optimized Down Fire Wide 10" Sealed
Under rear seat fitment for trucks and SUVs. Cut for the ResoNix GUS-10
The Down Fire Wide Format
Down Fire Wide is the Performance Optimized answer to a specific problem: the space under the rear seat of a truck or SUV, or a narrow cargo floor, is long and shallow, and the standard 30 by 15 inch Down Fire cabinet will not go in it.
This cabinet takes the same ResoNix GUS-10 and turns the footprint sideways. It runs 41 inches wide by 12 inches deep by 5.5 inches tall: 3 inches shallower front to back than the standard 30 x 15 cabinet and 11 inches longer. The airspace given up in depth is recovered along the length.
Which one to choose. If you have 15 inches of depth, the standard 30 x 15 ResoNix GUS-10 enclosure is the pick. Choose Down Fire Wide when depth is the limit: under a rear bench or on a narrow cargo floor, with at least 12 inches of depth and 41 inches of run.
Performance, Performance Optimized, and Micro
Proline X builds three tiers of Down Fire enclosure. The difference is not finish or materials, it is whether the cabinet was designed for a category or for a driver, and how much of the fitting work is already done for you.
| Performance | Performance Optimized | Micro Series | |
|---|---|---|---|
| Fitment | Universal. Accepts any subwoofer that clears the published cutout and mounting depth. | Woofer specific. Cut for one named subwoofer, with cutout, mounting depth, magnet clearance and displacement drawn in CAD from that driver. | Woofer specific. Cut for one named subwoofer. |
| Footprint | Sized to the driver diameter. 24.5 by 13.5 inches on the 10 inch. | Shared 30 by 15 inch platform on most builds. Down Fire Wide variants like this one run long and shallow for under seat fitment. | Compact per driver footprint. 21.5 by 14.5 inches on the 10 inch. |
| Front baffle | Single, 3/4 inch. | Double layer, outer layer machined as a flush recess. 1.5 inch. | Double, 1.5 inch. |
| Driver mounting | Solid flange. You drill your own mounting holes. | 8/32 threaded inserts, stainless machine screws included. | 8/32 threaded inserts, stainless machine screws included. |
| Joinery | V-groove and dado, CNC cut. | V-groove and dado, CNC cut, perimeter cross brace. | Stack fab, dowel reinforced. |
| Published alignment | Modeled Qtc profiles across a range of drivers. No single response curve. | A real predicted Qtc and F3 for that exact driver, calculated from its own Thiele-Small parameters. | Target alignment described in the listing. |
| Carpet | Gray standard, black optional. | Plush black. | Plush black. |
| Warranty | 1 year limited. | 1 year limited. | 2 years. |
Feet ship with every tier, uninstalled on purpose. Mount them where your floor wants them for a down fire install, or leave them off and run the cabinet front firing or up firing. The orientation is yours to choose.
This page is a Performance Optimized enclosure. The cutout, the cabinet height and the airspace all come from the ResoNix GUS-10's own published numbers. A Performance box fits your subwoofer. A Performance Optimized box was built for it.
Built Around the ResoNix GUS-10
The baffle is bored to the GUS-10's 235.08mm cutout, 9.255 inches, and the cabinet height clears its 3.996 inch mounting depth with 0.75 inches above the motor. The 277.5mm frame sits on the 12 inch deep baffle.
GUS stands for Geometrically Uncompromised Subwoofer. A patent pending FEA optimized overhung motor. Copper and aluminum shorting rings plus a full length copper shorting sleeve outside the gap, with the voice coil between the former and the sleeve, which keeps inductance stable across stroke while pulling heat out of the coil. A titanium voice coil former that eliminates eddy current drag and directs heat away from the internal neodymium magnet. A Nomex honeycomb core cone with carbon fiber facing.
ResoNix publishes full Klippel LSI and TRF data for every GUS driver and commits to doing it for every production batch.
Down firing is endorsed by the manufacturer. ResoNix states there is very little real world difference in sound between down firing and up firing, and to choose whichever makes the installation easier, more reliable and easier to service. The GUS vented rear cone assembly also means the pole vent can be completely obstructed with no negative effect.
Net Volume and Alignment
This cabinet holds 0.723 cubic feet net, from 0.760 gross, after the driver's 0.031 cubic feet of displacement.
Computed from ResoNix's published Thiele-Small parameters for each coil version, per coil version: Dual 4-Ohm: Qtc 0.648, Fc 36.2 Hz, F3 39.7 Hz. Dual 2-Ohm: Qtc 0.568, Fc 34.0 Hz, F3 44.3 Hz.
Height here is set by the driver, not the airspace. The 3.996 inch mounting depth puts the motor far enough into the cabinet that the height is fixed by motor clearance, 0.75 inch above the motor. At 5.5 inches tall the wide box holds 0.723 cubic feet net, more than the 0.59 cubic feet the standard 30 x 15 box was built to. More air lowers Qtc, which is the safe direction: a slightly more damped alignment with a gentler rolloff.
The Dual 4-Ohm is the better match of the two coil versions. The Dual 2-Ohm is designed around a smaller box, so here it lands more damped still: tighter transient control and a gentler rolloff at the cost of a few hertz.
These are anechoic figures. Firing down into the floor, the sealed rolloff meets rising cabin gain, so in-car response extends below them.
Down Fire Wide Construction
Cut with V-groove and dado joinery on our ShopSabre routers from Langboard Elite 3/4 inch MDF, a dense 48.5 lb/ft³ board with a 200 psi internal bond and 410,000 psi MOE. Every panel joint is a machined interlocking groove that mechanically locks before adhesive is applied, which keeps the cabinet airtight under sustained pressure cycling. Corners are square on Down Fire cabinets, no radii. Polyfill is installed as a light wall lining, finished in plush black carpet.
The cabinet measures 41 inches wide by 12 inches deep by 5.5 inches tall, measured in the down fire position, excluding standoffs. Custom-fit standoffs ship with the enclosure, uninstalled. They hold the 55mm ResoNix requires between the baffle surface and the floor, so plan the space around the cabinet height plus the standoffs.
1.5 Inch Double Baffle
Two 3/4 inch layers laminated to 1.5 inches, the outer layer machined as a flush recess so the driver bolts to the inner layer. 8/32 threaded inserts with stainless machine screws at every mounting location.
Standoffs Included
ResoNix specifies 55mm minimum from the baffle surface to whatever sits in front of the cone. On a down fire cabinet that is the floor, so custom-fit standoffs ship with every enclosure.
Windowed U-Brace
A windowed U-brace ties the long top and bottom panels together across the 41 inch span without walling off the airspace.
Side-Mounted Terminal Cup
Proline X ABS and carbon fiber composite cup with stainless hardware and copper ring terminals, side mounted and pre-wired in 12 gauge OFC, so it stays accessible with the baffle facing the floor.
Power and Wiring
ResoNix rates the GUS-10 at 500 watts RMS and states plainly that they do not underrate their drivers the way many manufacturers do. Burnt voice coils and damage from bottoming out are not covered under their warranty, and because these drivers stay linear right up to their limits it will not always be obvious when you are pushing too hard. An amplifier capable of more is fine so long as delivered power is held to the rating.
The GUS-10 is dual voice coil in Dual 2-Ohm and Dual 4-Ohm versions, so final impedance is set at the driver. Confirm the load against your amplifier's minimum stable impedance before powering the system.
Bring your own GUS-10 in either coil version; the driver is purchased directly from ResoNix Sound Solutions. The enclosure carries a 1 year limited warranty. Questions on fitment or amplifier matching, call 931-563-5151.
Cut for the Driver, Not the Catalog
Down Fire Wide, built for the space under a rear bench. We build every one to order in Tullahoma, Tennessee.
| Series | Proline X Performance Optimized Down Fire Wide |
| Compatible Driver | ResoNix GUS-10, Dual 2-Ohm or Dual 4-Ohm. Direct fit, no other driver |
| Enclosure Type | Sealed, down fire, floor coupled |
| Intended Fitment | Under the rear seat of trucks and SUVs, or narrow cargo floors, where depth is the limiting dimension |
| Chamber Configuration | Single chamber, windowed U-brace, one side-mounted terminal cup |
| External Width | 41 in |
| External Depth | 12 in |
| External Height | 5.5 in, measured in down fire position, excludes standoffs |
| Internal Volume, Gross | 0.760 cu ft |
| Internal Volume, Net Acoustic | 0.723 cu ft after displacement |
| Alignment, Dual 4-Ohm | Qtc 0.648, Fc 36.2 Hz, F3 39.7 Hz anechoic |
| Alignment, Dual 2-Ohm | Qtc 0.568, Fc 34.0 Hz, F3 44.3 Hz anechoic |
| Height Set By | Driver clearance: 0.75 in above the motor |
| Comparison, Standard Down Fire | 30 x 15 x 5.125 in, 0.59 cu ft net |
| Woofer Opening | 235.08mm / 9.255 in, direct fit |
| Mounting Depth | 101.5mm / 3.996 in, ResoNix spec |
| Driver Outer Diameter | 277.5mm with gasket |
| Min Front Clearance | 55mm from baffle surface, ResoNix spec |
| ResoNix Target For 0.707 Qtc, D4 | 0.6 cu ft |
| Driver Fs | 21.76 Hz (D4) / 20.37 Hz (D2) |
| Driver Qts | 0.39 (D4) / 0.34 (D2) |
| Driver Vas | 36.035 L (D4) / 36.634 L (D2) |
| Driver Sd | 346.4 cm² |
| Driver Xmax | 18mm one way linear, Klippel verified |
| Driver Power Handling | 500 W RMS. Do not exceed |
| Driver Cone | Nomex honeycomb core with carbon fiber facing |
| Driver Voice Coil | Copper on titanium former |
| Rear Venting | Vented rear cone assembly. Pole vent may be fully obstructed, ResoNix spec |
| Driver Displacement | 0.031 cu ft, published by ResoNix |
| Material | Langboard Elite 3/4 in MDF |
| Construction | ShopSabre CNC cut, V-groove and dado joinery, windowed U-brace |
| Front Baffle | 1.5 in double baffle, outer layer machined as a flush recess |
| Corner Profile | Square, Down Fire series standard |
| Driver Mounting | 8/32 threaded inserts, stainless machine screws included |
| Terminal Cup | One Proline X ABS and carbon fiber composite, side mounted |
| Internal Wiring | 12 gauge OFC |
| Damping | Polyfill installed, light wall lining |
| Standoffs | Custom fit, included, shipped uninstalled. Hold ResoNix's required 55mm from the baffle surface to the floor |
| Carpet | Plush black |
| Warranty | 1 Year Limited |
| Built In | Tullahoma, Tennessee |
01Is it a sealed driver?
Efficiency bandwidth product places the motor before anything else is decided.
02What the box does to it
0.723 cu ft against a 36.6 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 18.0 mm — and a bigger one once a subsonic filter stops it wasting travel below the passband.
| Param | Value | Unit | Note |
|---|---|---|---|
| Fs | 20.37 / 21.76 | Hz | free-air resonance |
| Qts | 0.340 / 0.390 | D2 / D4 | |
| Vas | 36.63 / 36.03 | L | equivalent compliance |
| Sd | 346.4 | cm² | effective piston area |
| Xmax | 18 | mm | one-way linear travel |
| Pe | 500 | W | continuous RMS |
| SPL | 81.4 | dB | 1 W / 1 m, derived from T/S |
Driver parameters as published by resonixsoundsolutions.com. Curves computed against this enclosure’s actual net airspace.
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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