Proline X
Proline X Enclosure | X Series | Fits Kicker Solo X 15" Subwoofer | Dual
SKU: Pro KIK 15D X
- Best For: Dual Solo-X 15" SUV Builds | Full-Size SUV Cargo Installs
- Tuning: 30 Hz
- Net Volume: 10.0 cu ft
- Construction: Triple Face Baffle | Extreme Cross-Bracing | Upfiring Drivers | Rear Port
Financing available — choose Shop Pay Installments at checkout.
Proline X Enclosure | X Series | Fits Kicker Solo X 15" Subwoofer | Dual
Proline X X Series | Pro KIK 15D Solo X
Dual 15" SUV-Style Enclosure | Upfiring Drivers | Rear Port | Built for Two Kicker Solo-X L7X
Two Solo-X 15" Drivers. SUV-Style. Built for the Cargo Floor.
The Pro KIK 15D Solo X is the largest enclosure in the X Series lineup and the only dual-driver configuration designed specifically for full-size SUV and truck cargo builds. Both Solo-X L7X 15" drivers mount through the top face and fire upward into the cargo area. The port exits through the rear panel and loads toward the rear gate. Two terminal cups sit on the rear panel opposite the port for clean wiring access from the gate area.
This is not a trunk-forward enclosure repositioned for SUV use. The SUV-style orientation is built into the design — the driver cutouts, port geometry, and terminal cup placement are all specified for upfiring driver orientation on a flat cargo floor. Running two Solo-X L7X 15" drivers in a shared 10.0 ft³ enclosure tuned to 30 Hz with 140 square inches of port area produces output at the top of what any single-vehicle enclosure in this lineup is capable of.
This is an enclosure-only product. You source the drivers — we handle the box.
Orientation — How This Enclosure Is Configured
The Pro KIK 15D Solo X uses a purpose-built SUV-style orientation. Every face of this enclosure has a defined function. Understand the layout before installation.
Panel Orientation Guide
10.0 ft³ — Dual 15" Specific Volume
Two Solo-X L7X 15" drivers in a shared enclosure require a volume calculated for their combined Thiele-Small parameters — not double the single 15" volume. 10.0 ft³ net is the correct airspace for two L7X 15" drivers in a shared vented alignment at 30 Hz, after accounting for port displacement, triple-layer baffle thickness, and bracing.
30 Hz Tuning
The same tuning frequency as the single 15" — arrived at independently for the dual-driver combined T/S parameters. Two L7X 15" motors in a correctly sized shared enclosure at 30 Hz produce the deepest, highest-output response in the X Series lineup.
140 sq in Port Area
Double the single 15" port area — scaled directly to the combined displacement of two L7X 15" drivers at sustained high-power input. At 140 square inches, air velocity stays clean at the combined rated input range of two competition-class 15" drivers. Port compression and chuffing are not acceptable at this output level — the port area ensures they do not occur.
Upfiring Configuration — Why It Works in SUVs
In a full-size SUV or truck, the cargo floor-to-headliner distance creates a large acoustic space directly above the enclosure. Upfiring drivers pressurize that space efficiently and the rear-exiting port loads toward the gate opening. This orientation consistently produces strong cabin pressurization in large-format vehicles where trunk-forward builds are not practical or possible.
Construction: The Most Demanding Build in the X Series
The Pro KIK 15D Solo X uses the same construction methodology as every Proline X enclosure — Langboard Elite MDF, V-groove and dado joinery, extreme internal cross-bracing, in-house terminal cups, hand-assembled in Tennessee. Two 406 oz. motor assemblies in a 10.0 ft³ enclosure at competition power levels represent the highest structural demand in the X Series lineup. The construction specs match that demand.
Triple-Layer Top Baffle
Both driver cutouts are in the top face of the enclosure, which serves as the mounting baffle. This panel carries the full weight and excursion load of two L7X 15" motor assemblies — 812 oz. of combined magnet weight cycling against a single panel at sustained high-power input. Triple-layer construction at the top baffle is not optional at this driver count and power class. It is the minimum correct specification for two 406 oz. motors in an upfiring orientation.
Extreme Internal Cross-Bracing
At 10.0 ft³ net, the internal panel spans are the largest in the X Series. The side panels, front, and bottom face all have significant unsupported surface area. Extreme cross-bracing at the structural level controls panel resonance across those surfaces at 30 Hz under combined dual-driver load. The result is an enclosure that stays acoustically inert regardless of what two Solo-X 15" drivers generate at full power.
Langboard Elite MDF — Named, Verified, Documented
Every panel is cut from Langboard Elite MDF — 3/4" (18mm) — a named, mill-documented panel stock produced in the United States. At 10.0 ft³ with 140 square inches of port area at dual-driver competition power, the pressure cycling through this enclosure is at the upper limit of what any single-enclosure build in the lineup generates. Langboard Elite's 200 psi internal bond rating is the structural foundation that keeps this enclosure performing correctly over time.
Langboard Elite — Published Mill Data
Density: 48.5 lbs/ft³ — higher density means less porosity, better screw retention, and reduced panel resonance under sustained bass pressure cycling
Internal Bond: 200 psi — resistance to delamination; two L7X 15" drivers at sustained competition power generate the highest pressure load in the X Series lineup
Modulus of Elasticity: 410,000 psi — panel stiffness under load; at 10.0 ft³ the unsupported panel spans require maximum stiffness to stay inert at 30 Hz
Face Screw Holding: 325 lbs — baffle hardware stays locked under the combined vibration load of two 406 oz. motor assemblies at excursion
Edge Screw Holding: 250 lbs — joint integrity at every panel edge connection throughout the enclosure's service life
V-Groove and Dado Joinery
Every panel joint uses V-groove and dado joinery — CNC-cut interlocking grooves that mechanically lock panels before adhesive is applied. In a 10.0 ft³ enclosure tuned to 30 Hz with two competition-class drivers generating combined back-pressure on every bass transient, joint integrity is structural integrity. The dado interlock resists shear forces regardless of glue condition over time.
Dual In-House Terminal Cups
Both terminal cups are built in-house at our Tennessee facility and mounted on the rear panel opposite the port. The recessed ABS/Carbon Fiber Composite cups feature stainless steel hardware, aluminum landing plates, and copper ring terminals, pre-wired with 12g OFC speaker wire. Rear panel placement puts both cups in accessible position from the rear gate area. Run 8 AWG or larger from each terminal cup to the amplifier at this power class.
ShopSabre CNC Routers
Every panel is machine-cut on ShopSabre industrial CNC routers at our Tennessee facility. Both square L7X 15" cutouts are machined to direct-fit the Solo-X mounting flanges on the top face. Internal volume of every Pro KIK 15D Solo X is identical to spec.
Hand-Assembled in Tennessee
Every enclosure is hand-assembled and inspected at our Tennessee facility before it ships. At this size and weight, build consistency matters — each unit is individually checked for volume accuracy, joint integrity, port clearance, and terminal cup seating before leaving the floor.
Finish & Shipping
The Pro KIK 15D Solo X is finished in Plush Black carpet with High Gloss Lasered Acrylic Inserts included. Single configuration — acrylic is standard. Lead time is 5–7 business days. [CONFIRM: acrylic panel placement — top face, front face, or both.]
Freight Shipping — Included in Price — Required
The Pro KIK 15D Solo X ships at 200+ lbs and requires freight shipping. Freight is included in the price — no additional charge at checkout. The freight carrier will contact you to schedule a delivery appointment. Someone must be present to receive the shipment. Inspect all packaging before signing and photograph every side before opening. Note any damage on the delivery receipt before signing — do not sign a clean receipt for a visibly damaged shipment. Contact us immediately if damage is found.
Due to size and weight, curbside delivery only. The carrier will not bring the enclosure inside. Arrange assistance for moving into your install location.
Every Proline X X Series enclosure carries a 2-year warranty covering manufacturing defects in materials and workmanship. Built in Tennessee and backed by Audio Intensity directly — no third-party claims process.
Fitment & Specifications
The Pro KIK 15D Solo X is purpose-built for two Kicker Solo-X L7X 15" drivers in an upfiring orientation on a flat cargo floor. Both square baffle cutouts are on the top face. The port exits the rear panel. Terminal cups are on the rear panel opposite the port. This enclosure requires a vehicle with a flat, unobstructed cargo floor area of at least 46.5" wide and 35" front-to-back. Measure your cargo floor before ordering.
Dimensional & Acoustic Specifications
External Dimensions: 46.5" W × 19.5" H × 35" D
Net Internal Volume: 10.0 ft³
Tuning Frequency: 30 Hz
Port Area: 140 sq in
Driver Orientation: Upfiring — top face
Port Orientation: Rear-firing — rear panel
Terminal Cups: Dual — rear panel, opposite port
Front Baffle (Top Face): Triple-Layer MDF
Recommended Power: 1000–2000W RMS per driver
Weight: 200+ lbs
Wiring Configurations
Two Single 2Ω Drivers — Parallel
Wire both drivers in parallel for a 1Ω final load. Requires an amplifier stable at 1Ω. Delivers maximum power transfer from high-current monoblocks rated at 1Ω.
Two Single 4Ω Drivers — Parallel
Wire both drivers in parallel for a 2Ω final load. Compatible with the widest range of high-output monoblock amplifiers. Most common wiring configuration for dual-driver competition builds.
Two Single 2Ω Drivers — Series
Wire both drivers in series for a 4Ω final load. Use when your amplifier is not stable at lower impedances. Output will be lower than parallel configurations at equivalent amplifier power.
Plan Before You Order
Select your driver impedance based on your amplifier's stable output impedance — not peak power rating. At 1000–2000W RMS per driver, plan your full electrical system before committing to amplifier selection. Contact us with your amplifier model and wiring plan for confirmation.
Ideal Install Applications
Full-Size SUV Cargo Builds
The upfiring orientation is optimized for full-size SUVs with flat, unobstructed cargo floors — Tahoe, Suburban, Yukon, Expedition, Navigator, and similar platforms. The drivers pressurize the cargo area directly above, the port loads toward the rear gate. Verify cargo floor dimensions and clearance to the headliner before ordering.
Full-Size Truck Bed Builds
With appropriate weatherproofing and bed liner protection, the upfiring configuration works in covered truck bed applications. The rear-exiting port loads toward the cab or tailgate depending on enclosure orientation. Contact us before ordering for truck bed application guidance.
Maximum-Output Dedicated Builds
Two Solo-X L7X 15" drivers in a correctly tuned 10.0 ft³ enclosure represents the highest single-enclosure output in the X Series lineup. This is a dedicated build — the vehicle is the enclosure space, and the enclosure is built accordingly.
Demo & Show Builds
The SUV-style upfiring configuration with acrylic inserts included makes this the most visually and acoustically impactful enclosure in the lineup. The drivers are visible from above, the acrylic identifies this as a purpose-built system, and the output backs up the visual at any demo event.
The Top of the X Series. Two 15" Drivers. Built in Tennessee.
The Proline X Pro KIK 15D Solo X is the largest, most powerful single-enclosure configuration in the X Series lineup. 10.0 ft³ net, 30 Hz tuning, 140 square inches of port area, two upfiring L7X 15" cutouts, rear-exiting port, dual terminal cups. Langboard Elite MDF. Triple-layer top baffle. Extreme internal cross-bracing. V-groove and dado joinery. Hand-assembled and inspected in Tennessee. Acrylic inserts included. Freight shipping included. Backed by a 2-year warranty.
You source the drivers. We handle the box. $1,750.00. Freight included. 5–7 business day lead time.
Audio Intensity and Proline X are not affiliated with Kicker. This enclosure is engineered to match the published Thiele-Small specifications of the Kicker Solo-X L7X 15".
| SKU | Pro KIK 15D Solo X |
| Enclosure Type | Ported / Vented — SUV Style |
| Configuration | Dual 15" — Shared Chamber |
| Compatible Driver | Kicker Solo-X L7X 15" × 2 |
| Driver Impedance | 1Ω DVC (49L7X151) or 2Ω DVC (49L7X152) — per driver |
| Driver Orientation | Upfiring — Top Face |
| Port Orientation | Rear-Firing — Rear Panel |
| Terminal Cups | Dual — Rear Panel, Opposite Port |
| Net Internal Volume | 10.0 ft³ |
| Tuning Frequency | 30 Hz |
| Port Area | 140 sq in |
| External Dimensions | 46.5" W × 19.5" H × 35" D |
| Top Baffle | Triple-Layer MDF |
| Internal Bracing | Extreme Cross-Bracing — Full Structure |
| Panel Material | Langboard Elite MDF 3/4" (18mm) |
| Joinery | V-Groove and Dado |
| Finish | Plush Black Carpet with Lasered Acrylic Inserts |
| Recommended Power | 1000–2000W RMS per driver |
| Weight | 200+ lbs |
| Warranty | 2 Years — Manufacturing Defects |
| Lead Time | 5–7 Business Days |
| Made In | Tennessee, USA |
| Shipping | Freight Included — Lower 48 States — Curbside Delivery |
Built From a Spec Sheet, Not a Sales Sheet
Every Proline X X 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 — 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 X 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
Why do the drivers fire upward instead of forward or rearward?
How do I wire two Solo-X 15" drivers in this enclosure?
What vehicles does this enclosure fit?
How does freight shipping work and what do I need to do at delivery?
What amplifier do I need for this enclosure?
Is this a shared-chamber enclosure or does each driver get its own chamber?
What is the lead time for this enclosure?
How do I secure this enclosure in my vehicle?
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