Proline X
Proline X Micro Series 15" Sealed Enclosure | Built for ResoNix GUS-15
SKU: M15-S Gus
- Best For: Reference-grade shallow 15" installs. Behind-seat trucks, SUV cargo, trunk floors where 8.25" depth is required and maximum low-frequency output is the goal.
- Power: Rated for up to 1,500W RMS (ResoNix GUS-15)
- Topology/Class: Sealed / Double-Layer Stack Fab / Dowel Reinforced / Front-Fire or Downfire
- Sonic Character: Reference-grade extension, ultra-low distortion, flat 0.707 Qtc alignment. Klippel-verified 25.89mm Xmax on a 15" cone: the most capable shallow-mount 15" available.
Financing available — choose Shop Pay Installments at checkout.
Proline X Micro Series 15" Sealed Enclosure | Built for ResoNix GUS-15
A Shallow 15" Built Around Real Engineering.
1.42 cu ft. Exactly Right.
The ResoNix GUS-15 produces 1,500 watts RMS from 5.93 inches of mounting depth with Klippel-verified Xmax of 25.89mm. ResoNix publishes a 0.707 Qtc target of 1.35 cubic feet. Add the driver's 0.072 cubic foot displacement and the correct gross build volume is 1.422 cu ft. This enclosure delivers 1.42 cubic feet net — the most structurally demanding, highest-power single-driver build in the Proline X Micro Series.
1.42 cu ft — How the Volume Was Calculated
ResoNix recommends 1.35 cubic feet of net acoustic airspace for the GUS-15 to achieve 0.707 Qtc. The GUS-15 has a published driver displacement of 0.072 cubic feet. Building to a gross volume of 1.35 cubic feet and installing the driver would leave only 1.278 cubic feet net — noticeably below the recommendation. The correct build target is 1.35 + 0.072 = 1.422 cubic feet gross, so that after driver displacement is subtracted the driver sees exactly 1.35 cubic feet of net acoustic airspace.
This enclosure delivers 1.42 cubic feet net after displacement — matching ResoNix's acoustic volume recommendation accurately. The 1.42 figure is the net acoustic volume the driver sees, not the gross box volume before displacement is accounted for.
The GUS-15 in a Sealed Enclosure — What the Numbers Mean
The GUS-15's published T/S parameters (D4 variant) show Fs at 17.11 Hz and Qts at 0.34. At 1.35 cubic feet sealed, the system Qtc targets 0.707 — flat anechoic response extending well below 20 Hz. The 15" cone area (Sd of 804.25 cm²) combined with 25.89mm of Klippel-verified one-way Xmax produces a displacement volume that translates directly to output. A 15" driver at this Xmax in the correct sealed enclosure delivers low-frequency output that no shallow 12" — including the GUS-12 — can match at the same power level.
Like the GUS-12, this is an SQ-oriented driver engineered for accuracy and deep extension. The 0.707 Qtc alignment produces a flat anechoic response with the low-frequency reach the driver's motor and suspension are designed to deliver. In a vehicle cabin, boundary gain below 80 Hz reinforces the driver's deep extension in the listening position. The GUS-15 in this enclosure is the most capable shallow-mount bass system available at this depth.
1,500W RMS Demands a Different Level of Construction
At 1,500 watts RMS the GUS-15 generates more internal pressure than any other single driver in the Micro Series lineup by a significant margin. The front baffle is a double-layer stack-fab build — two CNC-cut Langboard Elite MDF panels bonded to 1.5 inches total thickness. The stack-fab assembly is further reinforced with dowels throughout the build, adding mechanical alignment and shear resistance at every panel joint beyond what dado joinery and adhesive alone provide.
The 8.25-inch total depth gives panel walls more inherent geometric rigidity than the ultra-shallow builds in this series, but at 1,500 watts the increased excursion load and cone area of a 15" driver means the structural demands on every panel and joint are correspondingly higher. Langboard Elite MDF at 200 psi internal bond and 410,000 psi MOE is the correct panel spec for this application — not because it is the cheapest option that passes, but because it is the named, documented spec that holds under sustained high-power use.
1.42 cu ft Net — 1.35 Target + 0.072 Displacement
ResoNix's 0.707 Qtc target is 1.35 cu ft net. GUS-15 driver displacement is 0.072 cu ft. This enclosure is built to 1.35 + 0.072 = 1.422 gross volume, delivering exactly 1.35 cu ft net acoustic airspace after the driver is installed.
Klippel-Verified 25.89mm Xmax — 15" Cone Area
Xmax of 25.89mm at BL 70% across a 804.25 cm² effective cone area — the combination that defines real-world output capability. This is measured performance on a Klippel LSI system, not a manufacturer Xmax claim.
1.5" Double-Layer — Dowel Reinforced Stack Fab
Two bonded layers of Langboard Elite 3/4" MDF at 1.5 inches total, further reinforced with dowels throughout the stack-fab assembly. At 1,500 watts RMS, baffle resonance and panel flex are structural failure modes — this construction eliminates both.
8/32 Threaded Inserts — Machine Screws Included
The baffle is fitted with 8/32 threaded inserts on the back face. Stainless machine screws are included. The GUS-15 mounts to steel — not MDF. Consistent clamping force at all mounting points, no stripping under sustained 1,500-watt operation.
Proline X Terminal Cup — Pre-Wired with 12g OFC
The Proline X terminal cup is installed and pre-wired with 12-gauge OFC internally. Connect your amplifier run to the terminal and mount the driver. ResoNix recommends 10-gauge speaker wire from terminal to driver at 1Ω loads to maintain damping factor — factor this into your wiring plan.
Direct-Fit — Machined for the GUS-15
The baffle cutout is machined to the GUS-15's mounting diameter. The driver seals against its included rubber mounting ring gasket and mounts to the threaded inserts — no shimming, trimming, or gasketing tape required.
Front-Firing or Downfiring — Feet Included
Rubber feet for downfiring installation are included. The GUS-15's vented rear cone assembly allows the pole vent to be fully obstructed without acoustic penalty — downfire in a tight install is viable. ResoNix notes minimal real-world difference between orientations; choose based on install practicality.
Polyfill Pre-Installed
Polyfill is factory-installed. It acoustically dampens internal panel reflections without artificially altering volume. Factory installation ensures consistent packing density across every unit.
Dowel-Reinforced Stack Fab — 1,500W Structural Standard
Dowels throughout the stack-fab assembly add mechanical alignment and shear resistance at panel joints independent of adhesive condition. At 1,500 watts RMS the lateral and outward forces on panel joints are the highest of any single-driver build in this series. Dado joinery + adhesive + dowels — all three systems working together.
Ready to Mount. Ready to Wire. Built for Active Systems.
The enclosure ships fully prepped. The Proline X terminal cup is installed and pre-wired with 12-gauge OFC — connect your amplifier run and wiring is complete. The double-layer baffle uses 8/32 threaded inserts with stainless machine screws included. Rubber feet for downfiring are included. Polyfill is factory-installed. Minimum front clearance for the GUS-15 is 33mm — confirm this against your install location before mounting.
Impedance Options — D2 and D4
The GUS-15 is available as a Dual 2-ohm (D2) and Dual 4-ohm (D4). D2 T/S parameters are not yet finalized by ResoNix — D4 data is published and is the basis for this enclosure's volume calculation. Wire the D4 parallel for 2 ohms, series for 8 ohms. Wire the D2 parallel for 1 ohm, series for 4 ohms. At 1 ohm, use an amplifier explicitly rated for sustained 1-ohm operation. At 2 ohms, target a monoblock delivering 1,000–1,500 watts RMS. Do not exceed 1,500 watts RMS — ResoNix is explicit that overpower damage is not covered under warranty.
Where It Fits
At 28" × 17.5" × 8.25" and roughly 40+ lbs, this is the largest enclosure in the Micro Series. The 8.25" depth is what makes it viable in locations a conventional 1.35 cu ft sealed 15" box — typically 14–18" deep — cannot reach. Measure carefully before ordering:
- Trunk floor — full-size sedans, sport sedans, wagons
- Flat cargo floor — mid-size and full-size SUVs
- Behind-seat — full-size crew cab trucks with rear seat removed
- Under rear bench — full-size SUVs and vans
- SQ competition builds — where depth is the constraint and output is the goal
- High-output daily builds: systems targeting maximum extension
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. Internal volume, 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-15 (D2 / D4) |
| Enclosure Type | Sealed |
| Internal Volume (Net) | 1.42 Cubic Feet (1.35 target + 0.072 driver displacement) |
| Material | Langboard Elite 3/4" MDF |
| Construction | CNC-Cut Stack Fab / Dowel Reinforced |
| Front Panel Thickness | 1.5 Inches (Double-Layer Stack Fab) |
| External Width | 28 Inches |
| External Height | 17.5 Inches |
| External Depth | 8.25 Inches |
| Corner Geometry | 3" Radiused on All Four Corners (Standing Wave Control) |
| Woofer Opening | 356.17mm Direct Fit for ResoNix GUS-15 |
| Min Front Clearance | 33mm (per ResoNix specification) |
| Magnet Relief | Precision-Milled for Volume Adjustment and Voice Coil Cooling Airflow |
| Driver Mounting | 8/32 Threaded Inserts. Stainless Machine Screws Included. |
| Terminal Cup | Proline X ABS/Carbon Fiber. Stainless Hardware. Copper Ring Terminals. Pre-Wired. |
| Internal Wiring | 12-Gauge OFC (Oxygen-Free Copper) |
| Polyfill | Pre-Installed |
| Firing Direction | Front-Firing or Downfiring |
| Downfire Feet | Included |
| Finish | Plush Black Automotive Carpet |
| Design Revision | 5.20.26 |
| 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-15 subwoofer?
Why does this enclosure list 1.42 cubic feet when ResoNix recommends 1.35?
What makes the GUS-15 different from the GUS-12 in terms of output?
How does the GUS-15 sound in a vehicle cabin at 1.35 cu ft?
What amplifier does the GUS-15 require?
Why does this enclosure use dowel reinforcement?
Can I run this downfiring?
Where is the Proline X Micro Series 15" enclosure built?
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