Proline X PO 10D-S DF RSW sealed down-fire enclosure, front baffle with two flush-mount cutouts, 30 by 15 inches. Optimized for Alpine RS-W.
A promotional product graphic for a PROLINE PO 10D-S DF RSW speaker cabinet, showing the front and side dimensions of the dark gray speaker box with text callouts including 30 inches wide, 9.4 inches tall, and Alpine RS-W optimized design on a dark gradient background.
A promotional product graphic for a Proline PO 10D-S DF RSW woofers, showing a single black rectangular woofer with dimension callouts of 15 inches by 7.4 inches and a custom terminal cup, alongside feature text and the Alpine RS-W Series compatibility.
Proline X PO 10D-S DF RSW sealed down-fire enclosure, front baffle with two flush-mount cutouts, 30 by 15 inches. Optimized for Alpine RS-W.
A promotional product graphic for a PROLINE PO 10D-S DF RSW speaker cabinet, showing the front and side dimensions of the dark gray speaker box with text callouts including 30 inches wide, 9.4 inches tall, and Alpine RS-W optimized design on a dark gradient background.
A promotional product graphic for a Proline PO 10D-S DF RSW woofers, showing a single black rectangular woofer with dimension callouts of 15 inches by 7.4 inches and a custom terminal cup, alongside feature text and the Alpine RS-W Series compatibility.

Proline X

Performance Optimized Down Fire Sealed Dual 10" Enclosure | Alpine RSW10

SKU: PO 10D-S DF RSW

QUICK SPECS
  • Alignment: 0.50 cu ft net per chamber, 1.004 cu ft net total. Alpine's small-volume target, published F3 32 Hz. Qtc 1.49 / Fc 47 Hz / F3 32.9 Hz (D2), Qtc 1.94 / Fc 50 Hz / F3 34.1 Hz (D4)
  • Chambers: Two fully separate sealed chambers, 3/4" MDF full divider, one shared side-mounted terminal cup
  • Drivers: Pair of Alpine RS-W10D2 or RS-W10D4, 600W RMS each and 1200W combined, 20mm Xmax, 760 cm² total cone area, neodymium motor
  • Build: Proline X V-groove and dado joinery, double-layer 1.5" front baffles at both positions, perimeter cross-brace, 12g OFC to both driver positions
  • Cabinet: 30"W x 15"D x 7.4375"H measured in down fire position, square corners, no standoffs
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Shipping Included No freight charges at checkout. What you see is what you pay.
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Built in Tennessee CNC cut from 3/4" Langboard Elite MDF. V-groove and dado joinery.
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Advanced Terminal Cup Built in-house. ABS/Carbon Fiber. Stainless steel hardware. Copper ring terminals.
$ 299.99
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Proline X PO 10D-S DF RSW sealed down-fire enclosure, front baffle with two flush-mount cutouts, 30 by 15 inches. Optimized for Alpine RS-W.

Performance Optimized Down Fire Sealed Dual 10" Enclosure | Alpine RSW10

Regular price $ 299.99
Sale price $ 299.99 Regular price
Unit price
Enclosure Type Sealed
External Dimensions 30" W x 15" D x 7.4375" H (measured in down fire position)
Gross Volume 1.16 cu ft
Net Volume 1.004 total / 0.50 per chamber cu ft
Weight 33.5 lbs
Front Panel Thickness 1.5"
INSTALLER'S TAKE

A dual 10 in a cabinet 7.4375 inches tall. For context, the CompRT dual 10 in this same series stands 10.125 inches. Both are two-chamber sealed builds on the same footprint, but this one comes in nearly three inches shorter because the RS-W needs 0.50 net per chamber where the CompRT wants 0.79, and because Alpine's neodymium motor displaces 0.04 cubic feet against the CompRT's larger ferrite structure.

That is the whole argument for this driver. Two RS-W10s together take up less internal volume than one conventional ferrite 10 typically does. You get twice the cone area without paying for it in cabinet height.

Separate chambers are the standing rule on every dual sealed build we do, and this is why: two drivers sharing one volume interact acoustically, with each driver's compression stroke becoming the pressure environment the other is working against. That smears transients and blurs the alignment either would have alone. A full-height bonded divider stops it. Each RS-W10 sees its own 0.50 net cubic feet, its own polyfill, and produces its own clean alignment at Alpine's published 32 Hz F3.

Per driver you get 600 watts RMS, 20mm of one-way linear excursion, and 54mm of peak-to-peak mechanical travel. Across the pair that is 1200 watts RMS and 760 square centimeters of cone. The 4 inch high-temp voice coils, motor cooling fins and vented formers handle sustained output without thermal drama.

Wiring: one side-mounted cup feeds both driver positions in parallel. Set your final impedance at the drivers by how you wire each one's coils. Wire both identically, since mismatched wiring between chambers splits power unevenly. Alpine's application guide covers every option for both the D2 and D4 versions.

Product Details
Specifications
Performance Graphs
Materials
Product Details

Proline X Performance Optimized Down Fire Dual 10" Sealed

Cut and tuned for a pair of Alpine RS-W10 Shallows

V-Groove and DadoLangboard Elite MDF1.004 cu ft NetSeparate Chambers
1.004cu ft net total
1.49system Qtc, D2
32.9-34.1 HzF3 rolloff
7.4375 incabinet height

Performance, Performance Optimized, and Micro

Proline X builds three tiers of Down Fire enclosure. The difference is not finish or materials, it is whether the cabinet was designed for a category or for a driver, and how much of the fitting work is already done for you.

Performance Performance Optimized Micro Series
Fitment Universal. Accepts any subwoofer that clears the published cutout and mounting depth. Woofer specific. Cut for one named subwoofer, with cutout, mounting depth, magnet clearance and displacement drawn in CAD from that driver. Woofer specific. Cut for one named subwoofer.
Footprint Sized to the driver diameter. 24.5 by 13.5 inches on the 10 inch. Shared 30 by 15 inch platform on most builds, with cabinet height as the variable. A few drivers need a wider or deeper platform. Compact per driver footprint. 21.5 by 14.5 inches on the 10 inch.
Front baffle Single, 3/4 inch. Double, 1.5 inch, outer layer machined as a flush recess. Double, 1.5 inch.
Driver mounting Solid flange. You drill your own mounting holes. 8/32 threaded inserts, stainless machine screws included. 8/32 threaded inserts, stainless machine screws included.
Joinery V-groove and dado, CNC cut. V-groove and dado, CNC cut, perimeter cross brace. Stack fab, dowel reinforced.
Published alignment Modeled Qtc profiles across a range of drivers. No single response curve. A real predicted Qtc and F3 for that exact driver, calculated from its own Thiele-Small parameters. Target alignment described in the listing.
Carpet Gray standard, black optional. Plush black. Plush black.
Warranty 1 year limited. 1 year limited. 2 years.

Feet ship with every tier, uninstalled on purpose. Mount them where your floor wants them for a down fire install, or leave them off and run the cabinet front firing or up firing. The orientation is yours to choose.

This page is a Performance Optimized enclosure. The airspace, the cutout and the cabinet height all come from the Alpine RS-W10's own published numbers. A Performance box fits your subwoofer. A Performance Optimized box was built for it.

Built Around the Alpine RS-W10

Two chambers, two drivers, one cabinet 7.4375 inches tall on a 30 by 15 inch footprint. Each baffle is bored to the RS-W10's 9-5/8 inch, 243mm cutout, and both positions get the same alignment the single driver Down Fire cabinet uses. Against one RS-W10 in that same alignment, the pair delivers roughly 6 dB more maximum output with 760 cm² of total cone area.

Each driver ships as the RS-W10D2, dual 2 ohm, or the RS-W10D4, dual 4 ohm, rated 600 watts RMS and 1800 watts peak with 20mm of one way linear excursion and 54mm of peak to peak mechanical travel. The motor is a high-grade neodymium design driving a 4 inch high-temperature USA-wound voice coil, with Alpine's DD Linear dual magnetic gap for low distortion at high excursion, a vented coil former, and motor cooling fins. Frames are die-cast aluminum with black anodized threaded rear mounting frames and aluminum dust caps.

Neodymium is what keeps a dual cabinet this short. Two conventional ferrite 10s in separate chambers would need considerably more height for the same net volume per driver. At Alpine's published 0.04 cubic feet displaced each, these two drivers together take up less internal room than a single ferrite 10 typically does. Free air resonance is 30.0 Hz and efficiency bandwidth product runs 18.7 to 27.0 depending on coil, comfortably inside the range that calls for a sealed load.

Net Volume, Not Gross

Total internal gross volume is 1.084 cubic feet, split by the divider into two chambers. After Alpine's published 0.04 cubic feet of displacement per driver, that leaves 0.50 cubic feet net per chamber and 1.004 cubic feet net total. The per chamber figure is the number that matters acoustically: each driver only ever sees its own 0.50, which is Alpine's small-volume sealed target exactly, where Alpine publishes an F3 of 32 Hz.

True net, not marketing net. Internal volume is calculated from the machined cavity dimensions and the driver's published displacement, not estimated from external dimensions minus wall thickness.

Both coil variants are worth stating because the enclosure ships without drivers. In 0.50 cubic feet the Dual 2-Ohm, Qts 0.950 against a 20.64 litre Vas, lands at Qtc 1.49 with resonance lifted to 47 Hz and half power at 32.9 Hz. The Dual 4-Ohm, Qts 1.190 against a 23.35 litre Vas, lands at Qtc 1.94 with resonance at 50 Hz and half power at 34.1 Hz. Both are anechoic figures, before any cabin gain. Alpine's published sealed range runs 0.45 to 1.0 cubic feet per driver; we build 0.50 because it is what holds the cabinet under 7.5 inches.

Firing down into the floor, the sealed rolloff meets rising cabin gain below 60 Hz, and in-car response extends well below the published figure. Wire both drivers identically so both chambers stay matched.

Down Fire Construction

Cut with V-groove and dado joinery on our ShopSabre routers from Langboard Elite 3/4 inch MDF. Every panel joint is a machined interlocking groove that mechanically locks before adhesive is applied, which keeps both chambers airtight under sustained pressure cycling. Perimeter cross-bracing ties the long spans together. Corners are square on Down Fire cabinets.

Double Baffle, Flush Recess

Both front baffles are 1.5 inches, two bonded 3/4 inch sheets, with the outer layer machined as a flush recess so each driver bolts to the inner layer. That recovers 3/4 inch of internal clearance per chamber. Two sets of 8/32 threaded inserts with stainless machine screws included.

Side-Mounted Terminal Cup

One shared Proline X ABS and carbon fiber composite cup with stainless hardware, pre-wired in 12 gauge OFC to both driver positions. Side mounted so it stays accessible with the baffles facing the floor. Each driver is dual voice coil, so final impedance is set at the drivers.

Separate Chambers

A bonded full height 3/4 inch MDF divider gives each driver its own sealed airspace. Two drivers sharing one volume interact acoustically, each cone's compression phase becoming the other's pressure environment, which smears transients and blurs the alignment. Separate chambers eliminate that. Polyfill is pre-installed in each chamber.

Power and Warranty

Alpine rates each RS-W10 at 600 watts RMS and 1800 watts peak, so the pair takes 1200 watts RMS combined. Target 500 to 600 watts RMS per driver. In a 0.50 cubic foot chamber the cone reaches its 20.0mm one way limit somewhere between 998 and 1011 watts depending on coil, well above what the driver can absorb thermally, so the voice coil gives up before the suspension does.

A subsonic filter at 25 Hz, 24 dB per octave, stops the cone wasting travel below the passband and moves that same 20.0mm limit out to roughly 1005 to 1028 watts. That is about 1 percent more amplifier for the price of one filter setting.

Both versions are dual voice coil, so you set your final impedance at the drivers, and Alpine's application guide covers every wiring option. The enclosure carries a 1 year limited warranty. Bring your own pair of RS-W10D2 or RS-W10D4; the drivers are purchased separately.

Cut for the Driver, Not the Catalog

Two chambers machined to one driver's published numbers rather than one big box split down the middle by eye. Cut on our ShopSabre routers and built one at a time in Tullahoma, Tennessee.

Specifications
SeriesProline X Performance Optimized Down Fire
Compatible DriverAlpine RS-W10D2 (DVC 2Ω) or RS-W10D4 (DVC 4Ω) | Pair Required
Enclosure TypeSealed | Dual Driver | Down Fire Geometry | Floor-Coupled
Chamber ConfigurationTwo Fully Separate Chambers | Full Divider | Single Shared Side-Mounted Terminal Cup
Firing DirectionDown Firing, Both Drivers Fire Toward Floor
External Width30 Inches
External Depth15 Inches
External Height7.4375 Inches
Dimension ReferenceAll External Dimensions Measured In Down Fire Position
Total Internal Gross Volume1.084 Cubic Feet
Per-Chamber Net Volume0.50 Cubic Feet
Total Net Volume1.004 Cubic Feet
Alpine Published Sealed Range0.45 - 1.0 Cubic Feet Per Driver
Published F3 At This Volume32 Hz Per Driver (Alpine Small-Volume Sealed Spec)
System Qtc (Per Chamber)1.49 (D2) | 1.94 (D4)
Predicted Fc (Per Chamber)47 Hz (D2) | 50 Hz (D4)
Predicted F3 (Per Chamber)32.9 Hz (D2) | 34.1 Hz (D4)
Driver Fs30.00 Hz (Free-Air Resonance)
Driver Qts0.950 (D2) | 1.190 (D4)
Driver Vas20.64 L (D2) | 23.35 L (D4)
Cone Area380 cm² Each / 760 cm² Total
Driver Xmax (One-Way)20mm
Driver Xmech (Peak-to-Peak)54mm
Driver Power Handling600 Watts RMS / 1800 Watts Peak Each
Driver Voice Coil4 Inch, High-Temp USA Wire
Driver MotorHigh-Grade Neodymium, DD Linear Dual Magnetic Gap
Driver Displacement0.04 Cubic Feet Each (Published by Alpine)
Mounting DepthDirect Fit
Woofer Opening (Each)9-5/8 Inches / 243mm (Alpine Spec)
StandoffsNot Used On This Model
MaterialLangboard Elite 3/4" MDF
ConstructionShopSabre CNC / Perimeter Cross-Brace
JoineryV-Groove and Dado (CNC-Cut)
Panel Thickness3/4 Inch
Front Baffle ConstructionDouble-Layer 1.5" MDF at Both Driver Positions
Chamber Divider3/4" MDF Full Bonded Panel
Corner ProfileSquare (Down Fire Series Standard)
Driver Mounting8/32 Threaded Inserts | Stainless Steel Machine Screws Included | 2 Sets
Voice Coil ConfigurationDual Voice Coil Per Driver, Final Impedance Set At The Drivers
Terminal CupOne Proline X ABS/Carbon Fiber Composite | Side Mounted | 12g OFC Pre-Wired to Both Driver Positions
Internal Wiring12 Gauge OFC, Pre-Wired to Both Driver Positions
DampingPolyfill Pre-Installed Per Chamber
Recommended Power Per Driver500-600 Watts RMS (Alpine Rated: 600W RMS)
Carpet FinishPlush Black
Weight38 lb
Bundle OptionsEnclosure Only (Bring Your Own Pair of RS-W10D2 or RS-W10D4)
Warranty1-Year Limited (Enclosure)
Built InTullahoma, Tennessee, USA
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
SEALED 0–50 TRANSITION 50–100 PORTED 100–150 0 50 100 150 D2 27.0 D4 18.7
D2 · EBP 27.0D4 · EBP 18.7
EBP under 50 means a motor that wants a sealed load. The RS-W10D2 sits at 18.7–27.0, inside that band, which is why this is a sealed build rather than a ported one.

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
20 30 50 70 100 150 200 +6 +0 -6 -12 -18 -24 FREQUENCY · Hz LEVEL · dB −3 dB
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.

PXmax = 998–1011 W unfiltered  →  1005–1028 W with a 25 Hz subsonic
20 30 50 70 100 150 200 0 8 16 24 FREQUENCY · Hz CONE TRAVEL · mm PAST LINEAR TRAVEL · Xmax 20.0 mm 998 W reaches Xmax here
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.
ParamValueUnitNote
Fs30.00Hzfree-air resonance
Qts0.950 / 1.190D2 / D4
Vas20.64 / 23.35Lequivalent compliance
Sd380.0cm²effective piston area
Xmax20mmone-way linear travel
Pe600Wcontinuous RMS
SPL78.9dB1 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.

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

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.

Handcrafted in USA

Handcrafted in USA

Hand-assembled at our facility in Tullahoma, TN. Every enclosure is inspected before it ships.

Tuned to the Build

Tuned to the Build

Internal volume and port geometry are calculated to spec and CNC-cut to exact dimensions. The box performs the same way every time.

Frequently Asked Questions

Why two separate chambers instead of one shared volume?

How is a dual 10 enclosure only 7.4375 inches tall?

How does this compare to the single 10 inch RS-W Down Fire enclosure?

How is this enclosure wired, and how do I set my final impedance?

Where is the terminal cup located on a down fire enclosure?

Why are the corners square instead of radiused?

How is this enclosure built?

Are the Alpine RS-W10 subwoofers included with this enclosure?

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