JL Audio 10TW3 - D4 in Proline X Micro Series Enclosure|Proline X|Audio Intensity

Proline X

Proline X Single 10" Sealed Micro Series System | Loaded with JL Audio 10TW3-D4

SKU: M10-S JL SF

QUICK SPECS

Best For: Stealth installs / Extreme space-limited builds
Configuration: Single 10" Sealed — Micro Series
Volume: 0.50 ft³ Net
Tuning: N/A — Sealed
Sonic Character: Tight, Accurate, Musical

Proline X Enclosure — Built in Tennessee CNC-cut Langboard Elite 3/4" MDF, V-groove + dado joinery, recessed ABS/Carbon Fiber terminal cup.

Driver + Enclosure — Matched and Pre-Wired Subwoofer pre-installed and wired to the correct impedance. Connect your amplifier and it's ready to run.

Shipping Included Assembled to order in 2–5 business days. No freight charges at checkout.

$ 699.99 $ 799.99 Save $ 100.00

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What's Included

Proline X Micro Series sealed enclosure — single 10" configuration
JL Audio 10TW3-D4 10" thin-line subwoofer pre-installed
Pre-wired 12g OFC speaker wire — wired to 2-ohm (Dual 4-ohm parallel)
Recessed ABS/Carbon Fiber Composite terminal cup — stainless hardware, copper ring terminals
Pre-installed polyfill — acoustically tuned for this enclosure volume
Threaded inserts for secure driver mounting

Amplifier, power wire, and RCA cables not included

Proline X Single 10" Sealed Micro Series System | Loaded with JL Audio 10TW3-D4

$ 699.99

$ 699.99 ~~$ 799.99~~

Enclosure Type Sealed

External Dimensions 21.5" X 14.5" X 5.25"

Net Volume .50cu ft

Tuning Frequency N/A

Cutout Diameter Direct Fit

Front Panel Thickness 1.5"

Max Mounting Depth Direct Fit"

INSTALLER'S TAKE

The 10TW3-D4 is the driver that proves shallow-mount doesn't mean low-performance. The concentric tube motor is the reason — it's a fundamentally different architecture than a conventional motor shrunk to fit a shallow package. The 15.2mm Xmax is real and usable. In the 0.50 ft³ sealed Micro Series box with polyfill it performs like a properly loaded full-depth driver in a fraction of the space.

The 5.25" depth is the number to work with on fitment. Most under-seat truck applications and compact trunk builds can accommodate that. Measure carefully — 5.25" sounds small until you're working around seat rail brackets or cargo floor lips. The enclosure can also be run down-fire with rubber feet if clearance permits — that orientation works well in applications where the floor couples with the enclosure bottom.

One note: at 82.1dB sensitivity this driver is not the most efficient shallow-mount on the market. Feed it a clean 300–400W and it performs. Underpower it and you'll leave output on the table.

Product Details

The Proline X Single 10" Sealed Micro Series System pairs the JL Audio 10TW3-D4 10" thin-line subwoofer with a Proline X Micro Series sealed enclosure built at our Tennessee facility. Net internal volume is 0.50 ft³ — the target sealed volume for the 10TW3-D4 based on JL Audio's published T/S parameters. The 10TW3-D4 uses JL Audio's patented concentric tube architecture, which positions the voice coil beneath the dust cap while moving the motor structure forward — achieving 3.25" mounting depth with 15.2mm of one-way linear Xmax. That combination does not exist in a conventional driver. The system ships pre-wired to 2 ohms at the terminal cup. Connect your amplifier and it's ready to run.

Every panel is CNC-cut from 3/4" Langboard Elite MDF at our Tennessee facility — a mill-certified panel stock with a 200 psi internal bond rating, 410,000 psi modulus of elasticity, and 325 lb face screw holding strength. In a sealed enclosure this compact, panel integrity is the entire acoustic story. The sealed air volume controls cone motion — any flex or air leak at a joint directly corrupts that suspension. This box does not flex and does not leak.

Version III construction uses V-groove combined with dado joinery throughout. The terminal cup is built in-house at our Tennessee facility — ABS/Carbon Fiber Composite body, recessed mount, stainless steel hardware, aluminum landing plates, copper ring terminals, and 12g OFC speaker wire pre-installed. Polyfill is pre-installed and tuned for this specific volume. Nothing to source. Nothing to add. It ships ready to wire.

Shipping is included in the price. At 21.5" wide and 5.25" tall, this is one of the most compact loaded systems we build — but it still ships as a packaged freight unit. That cost is built into what you see. No freight line item on your order confirmation. What you see is what you pay.

JL Audio 10TW3-D4 in Proline X Micro Series Enclosure - Stackfab II

Enclosure Specifications

Enclosure Type	Sealed — Micro Series
Configuration	Single 10"
Net Volume	0.50 ft³
Tuning Frequency	N/A — Sealed
External Dimensions	21.5" W × 14.5" H × 5.25" D
MDF	Langboard Elite 3/4"
Joinery	V-groove + dado
Terminal Cup	Recessed ABS/Carbon Fiber Composite
Speaker Wire	12g OFC pre-installed
Acoustic Treatment	Polyfill pre-installed
Finish	Plush Black
Vehicle Fitment	Universal

Woofer Details

The JL Audio 10TW3-D4 is the benchmark shallow-mount 10" subwoofer in the car audio industry. It uses JL Audio's patented concentric tube architecture — the voice coil sits beneath the dust cap while the motor structure extends forward, which is what allows a 3.25" mounting depth while maintaining 15.2mm of one-way linear Xmax. Most shallow-mount drivers achieve low mounting depth by reducing motor size and accepting less excursion. The 10TW3-D4 does not make that tradeoff. The DMA-optimized motor maintains a linear magnetic field across the full excursion range, and the Floating Cone Attachment Method keeps the cone, voice coil, and spider aligned throughout. The result is a driver that performs like a full-depth subwoofer in a package that fits where conventional subs cannot. It is a Dual 4-ohm driver — pre-wired in parallel to 2 ohms at the terminal cup.

Brand + Model	JL Audio 10TW3-D4
Size	10"
RMS Power	400W
Voice Coil Config	Dual 4-ohm (wired to 2-ohm)
Voice Coil Diameter	2.5"
Xmax	15.2mm one-way linear
Fs	32.3 Hz
Sensitivity	82.1 dB
Frequency Response	24–200 Hz
Mounting Depth	3.25"
Cutout Diameter	9-1/16"
Cone Material	Mica-filled Polypropylene
Frame	Cast alloy

Why This Combo Works

JL Audio 10TW3-D4 in a Proline X 0.50 ft³ Sealed Micro Series Enclosure

The 10TW3-D4 has an Fs of 32.3Hz and is engineered specifically for compact sealed enclosures. JL Audio's published target for this driver is 0.50 ft³ sealed — that is exactly what this enclosure delivers. At that volume the driver's suspension and the sealed air spring combine to produce a flat, controlled response with strong transient accuracy. The 15.2mm Xmax gives it the mechanical travel to produce real output at this volume without running out of cone motion at listening levels.

The polyfill pre-installed in this enclosure is not filler — it acoustically increases the effective volume by slowing the speed of sound inside the box, which extends low-frequency response without increasing physical size. Combined with the 0.50 ft³ net volume, the system behaves closer to a 0.65–0.70 ft³ sealed enclosure acoustically. That is a meaningful difference at the low end for a box this size.

This system is for builds where space is genuinely constrained — sports car trunks, compact sedans, under-seat truck installs, or any application where a standard enclosure simply won't fit. At 21.5" wide and 5.25" deep it goes places nothing else does. The tradeoff versus a larger system is maximum output — this is an accuracy-first build, not an SPL build.

For amplifier power, target 300–400W RMS at 2 ohms. The 10TW3-D4 is rated at 400W RMS — stay in that range. A clean Class D monoblock at 300–400W is the correct match.

Materials

Material

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.

Specifications

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

Internal Bond

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.

Stiffness

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.

Screw Holding

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.

Sourcing

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.