Proline X
Proline X Micro Series Dual 12" Sealed Enclosure | Built for ResoNix GUS-12
SKU: M12D-S Gus
- Best For: High-output SQ builds: trunk floors, SUV cargo, maximum GUS-12 output at 7.5" depth
- Power: 1,600W RMS combined (800W RMS per ResoNix GUS-12)
- Topology/Class: Sealed / Dual Chamber / Double-Layer Stack Fab / Dowel Reinforced / Front-Fire or Downfire
- Sonic Character: Ultra-low distortion, maximum extension — dual Klippel-verified GUS-12 performance at 0.707 Qtc per chamber
Financing available — choose Shop Pay Installments at checkout.
Proline X Micro Series Dual 12" Sealed Enclosure | Built for ResoNix GUS-12
Dual GUS-12. 1.60 cu ft Total.
0.75 cu ft Acoustic Per Driver — ResoNix's Optimum.
Two ResoNix GUS-12 drivers. Two acoustically isolated sealed chambers. Each chamber delivers 0.80 cubic feet gross — which after the GUS-12's 0.047 cubic foot driver displacement equals exactly 0.75 cubic feet of net acoustic airspace per driver. ResoNix's published 0.707 Qtc target. In 7.5 inches of total depth. 1,600 watts RMS combined. The most technically demanding dual-driver build in the Micro Series.
0.80 cu ft Per Chamber — 0.75 cu ft Acoustic After Displacement
ResoNix recommends 0.75 cubic feet of net acoustic airspace per GUS-12 for 0.707 Qtc. The GUS-12 has a published driver displacement of 0.047 cubic feet. Building each chamber to a gross volume of 0.75 cubic feet and then installing the driver would leave only 0.703 cubic feet of acoustic airspace — below the recommendation. The correct gross build volume is 0.75 + 0.047 = 0.797 cubic feet per chamber.
Each chamber in the M12D-S GUS is built to deliver 0.80 cubic feet gross — after the GUS-12 is installed, each driver sees 0.75 cubic feet of net acoustic airspace, exactly matching ResoNix's published optimum. Total net acoustic volume across both chambers is 1.50 cubic feet. Total gross enclosure volume is 1.60 cubic feet. The listed 1.60 cu ft is the gross figure — the acoustic figure that matters for each driver is 0.75 cu ft per chamber.
Two GUS-12 Drivers: More Output, Same Alignment Character
The GUS-12's Qts of 0.28 and Fs of 14.54 Hz define both its performance ceiling and its operating requirements. A single GUS-12 in the correct enclosure produces flat anechoic response extending well below 20 Hz — but at 800 watts RMS and a single 12" cone, output in large vehicle cabins or competitive environments has a ceiling. Two GUS-12 drivers in isolated 0.75 cubic foot chambers double the cone displacement and the combined power handling to 1,600 watts RMS, while each driver still operates in exactly the enclosure volume it requires.
The acoustic character from the single GUS-12 build carries forward here. Both drivers have Qts of 0.28, and the system Qtc in each chamber targets 0.707: flat anechoic response with the deep low-frequency extension the driver's motor and suspension are engineered to deliver. Two drivers make that response roughly 3 dB louder at all bass frequencies. They do not change its character. The dual GUS-12 delivers more output than any other shallow 12" build in this depth class.
1,600W Combined — Construction Built to Match
The front baffle is a double-layer stack-fab build — two CNC-cut Langboard Elite MDF panels bonded to 1.5 inches total. The stack-fab assembly is reinforced with dowels throughout, adding mechanical alignment and shear resistance at every panel joint beyond what dado joinery and adhesive alone provide. At 1,600 watts RMS combined across two GUS-12 drivers, this is the correct structural standard — not overbuilt relative to the application.
The chamber divider is CNC-cut and dado-jointed to the same standard as the exterior panels. It is a structural element with the same rigidity and acoustic seal quality as any wall in the enclosure. Each chamber is independently sealed — neither driver's acoustic loading affects the other.
Impedance Wiring — Know Before You Order
0.75 cu ft Acoustic Per Driver — ResoNix's 0.707 Qtc Target
Each chamber is built to 0.80 cu ft gross. After the GUS-12's 0.047 cu ft displacement, each driver sees 0.75 cu ft of net acoustic airspace — exactly what ResoNix publishes for 0.707 Qtc. Both chambers are identical. Both drivers load correctly.
1,600W RMS Combined — Dual Klippel-Verified Xmax
Two GUS-12 drivers at 800W RMS each with 20.69mm Klippel-verified Xmax per driver. Combined cone displacement doubles the output potential of the single GUS-12 build across the entire bass frequency range — particularly below 30 Hz where cone displacement is the dominant output variable.
Dual Chamber — CNC Divider, Dado Jointed, Independently Sealed
A CNC-cut, dado-jointed chamber divider separates both driver volumes completely. Neither GUS-12 shares airspace with the other. Each driver loads into its own sealed 0.80 cu ft chamber — correct acoustic alignment on both sides, independently maintained.
1.5" Double-Layer — Dowel Reinforced Stack Fab
Two bonded layers of Langboard Elite 3/4" MDF at 1.5 inches total. Dowels reinforce the stack-fab assembly throughout. At 1,600 watts RMS combined, baffle resonance and panel flex are structural failure modes — this construction eliminates both.
8/32 Threaded Inserts — Machine Screws for Both Drivers
Both baffle positions are fitted with 8/32 threaded inserts. Stainless machine screws are included for both GUS-12 drivers. Each driver mounts to steel — consistent clamping force, no stripping, clean reinstallation at any service interval.
Single Proline X Terminal Cup — Pre-Wired to Both Drivers
One Proline X ABS/carbon fiber terminal cup with stainless hardware and copper ring terminals serves the entire enclosure. Pre-wired internally with 12-gauge OFC to both driver positions. One amplifier run — both drivers fed.
Same 0.707 Qtc Character as the Single GUS-12
Both GUS-12 drivers have Qts of 0.28, Fs of 14.54 Hz. The system Qtc in each chamber targets 0.707: flat anechoic response with deep extension. The dual build produces roughly 3 dB more low-frequency output than a single GUS-12 at equivalent power.
Dowel-Reinforced Stack Fab — 1,600W Structural Standard
Dowels throughout the stack-fab assembly add mechanical alignment and shear resistance at panel joints independent of adhesive condition. Combined with dado joinery and adhesive — three independent mechanical systems locking every joint against the sustained load of 1,600 watts RMS across two GUS-12 drivers.
Ready to Mount. Ready to Wire. Built for Active Systems.
The M12D-S GUS ships fully prepped. The Proline X terminal cup is installed and pre-wired with 12-gauge OFC to both driver positions — connect your amplifier run and wiring is complete. Both baffles use 8/32 threaded inserts with stainless machine screws included. Polyfill is factory-installed in both chambers independently. Rubber feet for downfiring are included.
Plan Your Wiring Before Selecting the Voice Coil Variant
The GUS-12 is available in Dual 2Ω (D2) and Dual 4Ω (D4) configurations. With two drivers, the wiring combinations produce multiple final impedance options. The most practical configuration for most builds is two D2 drivers, each wired series (4Ω per driver), then both in parallel (2Ω final) — broadest amplifier compatibility at a manageable load. See the impedance chart above and confirm your amplifier's stable impedance before ordering the driver variant.
Where It Fits
At 40" × 14.75" × 7.5", this enclosure is designed for applications where a single GUS-12 is not enough output and a conventional dual 12" sealed build is too deep. Measure carefully — 40" wide at 7.5" deep covers most full-size sedan trunks and SUV cargo floors:
- Trunk floor — full-size sedans and sport sedans
- Cargo floor — mid-size and full-size SUVs
- Behind-seat — full-size crew cab trucks
- Under rear bench — full-size vans and SUVs
- SQ competition builds — maximum GUS-12 output at minimal depth
- High-output systems: where distortion performance matters as much as SPL
All Proline X Micro Series enclosures carry a two-year manufacturer's warranty against defects in materials and workmanship. Built and inspected in our Tullahoma, Tennessee facility before shipment. Contact Audio Intensity directly for warranty support.
Made in Tennessee
Every Proline X Micro Series enclosure is CNC-cut and hand-assembled in Tullahoma, Tennessee on ShopSabre CNC routers. Chamber volume, divider placement, cutout geometry, dado joint depth, baffle layer count, dowel placement, and terminal positioning are all held to spec on every unit. Langboard Elite MDF throughout — named, mill-documented, published density and bond specifications.
| Compatible Driver | ResoNix GUS-12 (D2 / D4) — Quantity 2 |
| Configuration | Dual 12" — Dual Chamber Sealed |
| Internal Volume (Gross) | 1.60 Cubic Feet Total (0.80 cu ft per chamber) |
| Internal Volume (Net Acoustic) | 1.50 Cubic Feet Total (0.75 cu ft per driver after displacement) |
| Material | Langboard Elite 3/4" MDF |
| Construction | CNC-Cut Stack Fab / Dado Joinery / Dowel Reinforced |
| Front Panel Thickness | 1.5 Inches (Double-Layer Stack Fab) |
| External Width | 40 Inches |
| External Height | 14.75 Inches |
| External Depth | 7.5 Inches |
| Max Mounting Depth | 4.59 Inches (116.5mm) |
| Woofer Opening | 284.6mm Direct Fit — ResoNix GUS-12 (Both Positions) |
| Driver Mounting | 8/32 Threaded Inserts — Stainless Machine Screws Included (Both) |
| Terminal Cup | Proline X ABS/Carbon Fiber — Stainless Hardware, Copper Ring Terminals — Single Cup, Pre-Wired to Both Drivers |
| Internal Wiring | 12-Gauge OFC (Oxygen-Free Copper) |
| Polyfill | Pre-Installed Per Chamber |
| Firing Direction | Front-Firing or Downfiring |
| Downfire Feet | Included |
| Finish | Plush Black Automotive Carpet |
| Warranty | 2 Years — Proline X / Audio Intensity |
| Made In | Tullahoma, Tennessee, USA |
Built From a Spec Sheet, Not a Sales Sheet
Every Proline X Micro 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 across the 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 — 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 stack-fab layering 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 Micro 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.
Frequently Asked Questions
Does this enclosure include the ResoNix GUS-12 subwoofers?
The listing shows 1.60 cu ft — is that the volume each driver sees?
What is the correct way to wire two GUS-12 drivers in this enclosure?
How does the dual GUS-12 system sound in a vehicle cabin?
What amplifier does this system require?
Why does the dual GUS-12 have only one terminal cup instead of one per chamber?
How does the dual GUS-12 compare to the single GUS-12 build?
Where is this enclosure built?
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