Alpine RSW10D4 Shallow Subwoofer in Proline X Micro Series Enclosure

Proline X

Proline X Single 10" Sealed Micro Series System | Loaded with Alpine RSW10D4

Q: What amplifier power is ideal?

I recommend an amplifier rated between 450 W and 650 W RMS. You can wire the dual 4 Ω coils in series (8 Ω) or parallel (2 Ω) to match your amp’s stable impedance. Running the amp at roughly 75% of its max power yields clean output with headroom for dynamic peaks. Always set gain controls by ear and use a test tone to avoid clipping.

Q: Will it fit under my seat?

Measure your vehicle’s under-seat area for at least 6 in of clearance in height and 21 in in width. The enclosure is 5.25 in deep and the woofer mounts at 3.25 in, leaving room for wiring and carpet clearance. Many trucks and SUVs offer sufficient space. Always test-fit before final installation to confirm clearance.

Q: Can I use this sub in a ported box?

Alpine recommends the RSW10D4 in a sealed enclosure for optimal performance. Porting this driver requires precise tuning of port dimensions and box volume. A poorly tuned port can raise resonance and introduce unwanted boominess. If you need a ported solution, consider a custom enclosure designed for that format.

Q: What wiring options do I have?

You can wire the dual 4 Ω coils in series for an 8 Ω load, or in parallel for a 2 Ω load. Series wiring suits amps that perform best into high impedance. Parallel wiring delivers more current for greater output, provided your amp handles 2 Ω safely. Always consult your amplifier manual and verify stable operation at your chosen impedance.

Q: What vehicle types suit this enclosure?

This compact system fits most cars, trucks, and SUVs under the front or rear seat. Its low profile makes it ideal for cab-over-engine trucks, mid-sized sedans, and crossover SUVs. It also works well in small off-road vehicles where space is limited. You can install it without drilling or permanent modifications.

Q: Can I mount the enclosure vertically?

Yes. The sealed design allows flexible orientation. You can stand it upright behind a seat back or lay it flat under the seat. Just ensure the terminal cup remains accessible and that wiring has proper strain relief. Avoid mounting it where road debris or moisture might collect.

Q: What is the lead time and how does shipping work?

This system is assembled to order in Tullahoma, Tennessee. Allow 2–5 business days for assembly before it ships. Shipping to the lower 48 states is included — no freight charges added at checkout. You'll receive a tracking number when the order ships.

Q: What impedance does this system present to my amplifier?

The RSW10D4 is a Dual 4-ohm subwoofer. It ships pre-wired in parallel to a 2-ohm load at the terminal cup. Most Class D monoblocks are rated at 2 ohms — connect your amplifier's speaker wire to the terminal cup and you're done. No rewiring required.

SKU: M10-S ALP D4

QUICK SPECS

Best For: High-output stealth installs / Space-limited SQ builds
Configuration: Single 10" Sealed — Micro Series
Volume: 0.50 ft³ Net
Tuning: N/A — Sealed
Sonic Character: Deep, Accurate, High-Output

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 No freight charges at checkout on orders to the lower 48. Alaska, Hawaii, and international orders are quoted live rates at checkout.

$ 899.99

Hurry! Only 2 left in stock.

Financing available — choose Shop Pay Installments at checkout.

What's Included

Proline X Micro Series sealed enclosure — single 10" configuration
Alpine RSW10D4 10" shallow-mount 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 Alpine RSW10D4

$ 899.99

Enclosure Type Sealed

External Dimensions 21.5" × 14.5" × 5.25"

Net Volume .50cu ft

Tuning Frequency N/A

Cutout Diameter Direct Fit

Front Panel Thickness 1.5

Max Mounting Depth 3.5"

INSTALLER'S TAKE

The RSW10D4 is a step up in output from the TW3-D4 in the same enclosure footprint. The 4" neodymium voice coil at 3.25" depth is Alpine's answer to JL Audio's concentric tube — different engineering path to a similar goal, with a higher power ceiling as a result. In the 0.50 ft³ Micro Series box with polyfill, the RSW10D4 runs deeper and louder than most people expect from a system this size.

The impedance wiring is the same as the TW3-D4 version — Dual 4-ohm wired parallel to 2 ohms, pre-done at the terminal cup. Verify your amplifier is rated for 2-ohm operation. The RSW10D4 needs 450–600W RMS to perform at its capability. An underpowered amp on a 600W driver is a common install mistake — budget for the amplifier accordingly.

At 21.5" × 14.5" × 5.25" the fitment story is identical to the TW3-D4 Micro Series system. Same footprint, same install locations. The decision between the two comes down to power budget and output requirements.

Product Details

Proline X Micro Series Enclosure for the Alpine RS-W10D4

Cut and tuned for the Alpine RS-W10D4

CNC Stack-Fab Langboard Elite MDF 0.50 cu ft Net Fits Alpine RS-W10D4

0.50cu ft net

1.937system Qtc

34 HzF3 rolloff

3.25 inRS-W10D4 mounting depth

Built Around the Alpine RS-W10D4

Nothing about this box is generic. Every layer is cut to the RS-W10D4's published sealed target, with clearance cut for its 3.25 in mounting depth.

The RS-W10D4 carries a published Fs of 31 Hz, Qts of 1.19 and Vas of 23.35 litres, and an EBP of 21, which puts it in sealed enclosure territory. We ran the alignment math on that data and built the box to land where it belongs.

Net Volume, Not Gross

We build this cabinet at 0.50 cubic feet net, against a published recommendation of 0.45 to 1.0 cu ft. The volume quoted is true net internal airspace, measured after the walls, bracing and driver displacement are accounted for.

True net, not marketing net. Internal volume is calculated by summing each CNC cut layer's opening, not estimated from external dimensions minus wall thickness.

Proline X Micro Series Construction

This enclosure is stack fabricated 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 layer is a precision cut ring and the stacked layers do the joining themselves, so there is no butt joint or dado to flex or leak. Dowel reinforcement runs between layers as tension hardware only.

Threaded Inserts, Not Wood Screws

8/32 threaded inserts are set on the backside of the baffle so the driver mounts on machine screws. Pull it a dozen times and the threads are still there.

Pre-Wired Terminal Cup

Proline X ABS and carbon fiber composite cup with stainless hardware and copper ring terminals, pre-wired internally with 12 gauge OFC. No CCA anywhere in the build.

Damped and Finished

Polyfill is pre-installed to smooth the in box response, and the shell is wrapped in plush black carpet. Built in Tullahoma, Tennessee.

Enclosure Only or Loaded

Order the enclosure bare and mount your own RS-W10D4, or order it loaded and we mount the driver, dress the wiring and ship it ready to bolt in.

Sealed Enclosure Performance: Pre-Calculated

Using the published Thiele Small parameters for the Alpine RS-W10D4, here is the predicted Qtc, system resonance (Fc) and F3 rolloff for this enclosure. Calculated with the same formulas as the Audio Intensity Sealed Box Calculator.

Alpine RS-W10D4 4 ohm + 4 ohm | Qts 1.19 | Fs 31 Hz | Vas 23.35 L

Enclosure Size	Qtc	Fc	F3
0.50 cu ft as built	1.937	50.5 Hz	34.1 Hz

Alpine RS-W10D4 Frequency Response | Sealed, 0.50 cu ft

0.50 cu ft (Qtc 1.937) -3dB reference

Note on this alignment: Alpine publishes a Qts of 1.19 for the RS-W10D4, which is high for a sealed application. In 0.50 cubic feet that produces a rise around system resonance rather than a flat response, along with an F3 of 34.1 Hz. Alpine's own sealed recommendation for this driver is 0.45 to 1.0 cubic feet, and the figure stays above 1.6 across that whole range. The numbers above are calculated straight from Alpine's published parameters, not adjusted. Run your own numbers in the Sealed Box Calculator.

Cut for the Driver, Not the Catalog

Select your configuration above. This enclosure ships free to the lower 48 with a 2 year limited warranty, built one at a time in Tullahoma, Tennessee.

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

Performance Graphs

Net airspace

0.50

cu ft per chamber

System Qtc

1.49–1.94

sealed

Half power

32.9–34.1

Hz · F3

Xmax at

998

W RMS · no filter

With 25 Hz subsonic

1005

W RMS · +1%

Amplifier

500–600

W RMS recommended

This enclosure holds 0.50 cu ft net per chamber. In it the Alpine RS-W10D2 runs a system Qtc of 1.49–1.94 with half power at 32.9–34.1 Hz, and the cone reaches its 20.0 mm travel limit at 998 W, above the driver’s 600 W thermal rating, so heat stops you before travel does. Run a subsonic filter at 25 Hz and that becomes 1005 W — +7 W, or 1 percent more power for the same 20.0 mm of travel.

01Is it a sealed driver?

Efficiency bandwidth product places the motor before anything else is decided.

EBP = Fs ÷ Qes = 18.7–27.0

D2 · EBP 27.0D4 · EBP 18.7

Under 50 means a motor that wants a sealed load. The RS-W10D2 sits at 18.7–27.0, well inside that band, which is why this is a sealed wedge and not a ported build.

02What the box does to it

0.50 cu ft against a 20.6 L Vas.

α = Vas ÷ Vb = 1.46 · Fc = Fs√(α+1) = 47–50 Hz · Qtc = 1.49–1.94

D2 · Qtc 1.49, Fc 47 Hz, F3 32.9 HzD4 · Qtc 1.94, Fc 50 Hz, F3 34.1 Hz

The box lifts resonance from 30.0 Hz free-air to 47–50 Hz and half power lands at 32.9–34.1 Hz, anechoic, before any cabin gain. This enclosure ships without a driver, so both coil variants the maker offers are plotted. They do not load the same box the same way.

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 20.0 mm — and a bigger one once a subsonic filter stops it wasting travel below the passband.

P_Xmax = 998–1011 W unfiltered → 1005–1028 W with a 25 Hz subsonic

D2 · 1011 W, no filterD4 · 998 W, no filterD2 · 1028 W with subsonic at 25 Hz, 24 dB/octD4 · 1005 W with subsonic at 25 Hz, 24 dB/octXmax 20.0 mm one-way

Every trace touches the limit and no further, because each is drawn at the exact power that puts that coil on 20.0 mm. Unfiltered that is 998 W, reached first at 47 Hz. It sits above the 600 W the driver can take thermally, so the voice coil gives up before the suspension does. The dashed traces are the same driver behind a subsonic filter at 25 Hz, 24 dB/oct: stopping the cone wasting travel below the passband lets it take 1005 W before hitting the same 20.0 mm. That is 1 percent more amplifier for the price of one filter setting.

Param	Value	Unit	Note
Fs	30.00	Hz	free-air resonance
Qts	0.950 / 1.190		D2 / D4
Vas	20.64 / 23.35	L	equivalent compliance
Sd	380.0	cm²	effective piston area
Xmax	20.0	mm	one-way linear travel
Pe	600	W	continuous RMS
SPL	78.9	dB	1 W / 1 m, derived from T/S

Driver parameters as published by Alpine R-Series Shallow application guide. Curves computed against this enclosure’s actual net airspace.

Woofer Details

The Alpine RSW10D4 is a shallow-mount 10" subwoofer from Alpine's R-Series lineup, engineered around Gen2 DD-Linear Magnetic Circuit technology. At 3.25" mounting depth it delivers 20mm of one-way cone excursion and 600W RMS power handling — the same excursion capability as Alpine's full-size R-Series drivers in a package that fits where standard-depth motors cannot. The 4" neodymium voice coil is larger than most shallow-mount competitors at this depth, which is what enables the 600W RMS rating and the 20mm Xmax simultaneously. Alpine's die-cast aluminum frame provides rigid support that eliminates the basket flex common in stamped steel designs at sustained high power. Frequency response extends down to 29Hz in a sealed enclosure. The RSW10D4 is a Dual 4-ohm driver — pre-wired in parallel to 2 ohms at the terminal cup.

Brand + Model	Alpine RSW10D4
Size	10"
RMS Power	600W
Peak Power	1200W
Voice Coil Config	Dual 4-ohm (wired to 2-ohm)
Voice Coil Diameter	4"
Xmax	20mm one-way
Frequency Response	29–200 Hz
Motor	Gen2 DD-Linear Magnetic Circuit — neodymium
Frame	Die-cast aluminum
Mounting Depth	3.25"
Cutout Diameter	9.25"

Why This Combo Works

Alpine RS-W10D4 in a Proline X 0.50 Cubic Foot Sealed Micro Series Enclosure

Alpine publishes 0.50 cubic feet as the sealed recommendation for the RS-W10D4, and that is exactly what this cabinet delivers. Where the JL 10TW3-D4 in the same enclosure achieves its performance through concentric tube architecture, the RS-W10D4 gets there through Alpine's Gen2 DD-Linear magnetic circuit with a neodymium motor. High flux density in a compact footprint is what allows 20mm of Xmax and 600 watts RMS at a 3.25 inch mounting depth.

The 600 watt rating is the real difference between this and the TW3 in the same box. Fifty percent more rated power at the same Xmax in the same 0.50 cubic feet means meaningfully more output headroom. Response extending to 29 Hz also reaches lower than most shallow mount drivers manage in a sealed alignment.

That makes this the choice when output and low end extension matter more than absolute accuracy. If you want the flattest, most transparent shallow mount system we build, the TW3 in this cabinet is the better answer. If the TW3's 400 watt ceiling is the constraint, this is the one.

For amplifier power, target 450 to 600W RMS at 2 ohms. A Class D monoblock rated 500 to 750 watts at 2 ohms puts you in the right operating range. Do not underpower it. The RS-W10D4 is rated for 600 watts and performs best when fed adequate clean power rather than a clipped signal from something smaller.

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, 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.

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.