Proline X

Performance Optimized Wedge Sealed Dual 12" Enclosure | One Audio RSq3

Q: Will this enclosure fit both the RSq3 D1 and the RSq3 D2?

Yes. Both coil versions share the same frame, the same 11.125 in cutout and the same 8.50 in mounting depth, so the baffle is cut once and fits either.They land close acoustically too: Qtc 0.679 on the D1 and 0.649 on the D2 in this cabinet. The choice between them is an impedance decision, not an enclosure one, and on this driver that decision matters more than usual.

Q: Why 1.20 cubic feet net?

That is the published sealed recommendation for the RSq3, and it produces a well damped alignment on both coils: Qtc 0.649 to 0.679 with F3 between 39.6 and 40.8 Hz.Each chamber is 1.43 cubic feet gross. The RSq3 displaces 0.23 cubic feet, which is two to four times what a typical 12 inch takes out, so the cabinet has to be built noticeably larger than the net figure alone would suggest.

Q: What amplifier power should I run, and what impedance?

The RSq3 is published at 1500 watts each, so 3000 watts across the pair. Impedance is where this driver needs care: it comes as a dual 1 ohm or a dual 2 ohm.A single dual 1 ohm gives 2 ohms in series or 0.5 ohms in parallel, and almost nothing is stable into 0.5. A single dual 2 ohm gives 4 ohms or 1 ohm. With two drivers the low combinations get worse: all four coils of a dual 1 ohm pair in parallel is 0.25 ohms, which is effectively a short. Aim for 1 or 2 ohms on the D1 pair, 2 or 4 ohms on the D2 pair. Work out the wiring before you choose the amplifier.

Q: How does a wedge enclosure improve the sound in a trunk installation?

The angled seat-side face matches the roughly 20 degree lean of a factory rear seat, so the cabinet sits flat against it instead of leaving a wasted triangle. The vertical trunk-lid-side face carries the driver, firing rearward into the trunk cavity.Firing rearward means output loads into the trunk volume and reaches the cabin through the rear seat and deck rather than beaming at the back of your head, which makes it easier to keep the stage forward. The taper also gives height back where the lid closes, so you keep usable cargo space.

Q: Why is the front baffle double-layered?

The baffle is two bonded 3/4 inch sheets, 1.5 inches through. A subwoofer pushes as hard against its mounting surface as it does against the air, and a single 3/4 inch panel flexes under that load, which smears output and works the driver loose.That matters more than usual here. The RSq3 is a heavy, long throw driver, so the reaction load into the baffle is high. The 1.5 inches also gives the threaded inserts real material to hold in.

Q: What is the expected low-frequency extension?

Anechoic F3 lands between 39.6 and 40.8 Hz depending on coil, at Qtc 0.649 to 0.679. That is a properly damped sealed alignment rather than a peaked one.Those figures are anechoic and exclude cabin gain. In a car the transfer function of the cabin adds real output below 50 Hz, so in-vehicle response runs deeper than the number above.

Q: Do I need to add polyfill or damping?

No. Polyfill is already installed as a light wall lining to control internal reflections, and the quantity is chosen so it does not change the acoustic volume.Do not add more. Packing a sealed box with fill makes it behave as though it were larger, which would move the alignment off the 1.20 cubic feet this driver is specified for.

Q: Are the One Audio RSq3 included?

No. This is an enclosure only. You receive the cabinet finished in plush black carpet, with threaded inserts at both driver positions, stainless machine screws, one side-mounted pre-wired terminal cup and the polyfill lining already in place.The two RSq3 drivers are purchased separately. The cabinet is cut direct fit to that driver, so it is not a general purpose 12 inch box.

SKU: PO 12D-S W RSQ3 BB

QUICK SPECS

Best For: Dual One Audio RSq3 Trunk-Fit SQ Builds
Net Volume: 1.20 cu ft per driver (1.43 cu ft Gross)
Alignment: Qtc 0.679 (D1) / 0.649 (D2), F3 39.6 to 40.8 Hz
Driver Match: One Audio RSq3 (D1 or D2)
Watch the impedance: D1 parallels to 0.5 ohms, D2 to 1 ohm
Construction: Dual Chamber | Rear-Firing Wedge | V-Groove/Dado | Double 1.5" Baffle | Threaded Inserts

Shipping Included No freight charges at checkout. What you see is what you pay.

Built in Tennessee CNC cut from 3/4" Langboard Elite MDF. V-groove and dado joinery.

Advanced Terminal Cup Built in-house. ABS/Carbon Fiber. Stainless steel hardware. Copper ring terminals.

$ 399.99

Acrylic Insert Color

In Stock and Ready to Ship

Financing available. Choose Shop Pay Installments at checkout.

Performance Optimized Wedge Sealed Dual 12" Enclosure | One Audio RSq3

Enclosure Type Sealed

External Dimensions 32.00" W x 16" H x 17.77" D at base tapering to 11.94" D at top

Net Volume 2.40cu ft

Tuning Frequency N/A

Cutout Diameter Direct Fit

Front Panel Thickness 1.5"

Max Mounting Depth Direct Fit

INSTALLER'S TAKE

Check the impedance before anything else. The RSq3 comes dual 1 ohm or dual 2 ohm and the parallel options are brutal: 0.5 ohms on a single D1, and 0.25 ohms if you parallel all four coils of a D1 pair. That is not a load most amplifiers survive. Series wiring is the default answer on this driver.

This driver displaces 0.23 cubic feet, two to four times a normal 12 inch, so the cabinet is bigger than the 1.20 net figure suggests. Gross is 1.43 per chamber. Do not compare the external size to another 12 inch box and assume we over built it.

Measure the base depth. The cabinet is 17.77 inches deep at the trunk floor and 11.94 at the top, and it is 32.00 wide. The floor dimension decides whether it goes in. This one is 1.77 in deeper than it is tall, which is unusual for a wedge and comes from the driver's depth and displacement.

Both coils land well damped: Qtc 0.679 on the D1 and 0.649 on the D2, F3 39.6 to 40.8. Unlike some drivers in this program there is no awkward alignment story to manage here.

Polyfill is already in as a wall lining. Adding more makes the box act larger and walks the alignment off the published target.

Product Details

Performance Optimized Wedge | One Audio RSq3

Dual 12" Sealed Wedge Enclosure | Rear-Firing Trunk-Load Design

1.20 ft3 Net Per Driver1.43 ft3 Gross Per ChamberQtc 0.65 to 0.68Rear-Firing Wedge32.00" x 16" x 11.94/17.77"Built in Tennessee

The One Audio RSq3 in a Dual-Driver Sealed Wedge

One Audio's Reference SQ 12 inch. A 76 mm four layer round wire coil on an 82 mm wind height, quoted at 32 mm of Xmax, with a moving mass north of 320 grams and a 1500 watt power rating. It is a heavy, long throw driver, and the numbers below follow from that.

1.43 cu ft gross per chamber produces 1.20 cu ft net after the driver's 0.23 cu ft displacement. That displacement is two to four times what a typical 12 inch takes out of a box, which is why this cabinet is larger than its net volume alone would suggest.

Two Fully Separate Chambers

A full divider runs floor to ceiling and front to back, giving each RSq3 its own sealed 1.43 cu ft chamber. Neither cone loads against the other, so the pair stays predictable under hard excursion instead of modulating each other's air load. Each chamber is cut to the same volume as the single driver version of this cabinet, so the alignment is identical whichever you buy.

Trunk-Load Wedge Design Explained

The RSq3 mounts on the vertical trunk-lid-side face and fires rearward into the trunk cavity.

Seat-Side Face Matches Seat Lean

Angled face matches the roughly 20 degree factory seat lean.

Trunk-Lid-Side Face Fires the Woofer

Vertical baffle, cone firing rearward into the trunk cavity.

Trunk Cavity Loading

The trunk acts as an acoustic extension for a smoother presentation.

Preserves Trunk Cargo Space

The wedge tucks against the seat back and the space in front stays usable.

Engineered for the One Audio RSq3

1.20 cubic feet net per driver is the published sealed recommendation for this driver, and it produces a well damped alignment on both coil versions. Calculated from One Audio's own published Thiele-Small parameters, which they give separately for each coil.

Alignment Numbers

RSq3 D1 Qtc 0.679 · RSq3 D2 Qtc 0.649 · fc 37.2 to 38.0 Hz · F3 39.6 to 40.8 Hz anechoic

Mounting Geometry

Vertical baffle CNC cut to 11.125 in (283 mm). Driver mounting depth 8.50 in. Threaded inserts pressed into the baffle backside at every mounting location.

Performance Series Construction, Driver-Specific Tuning

Langboard Elite MDF

Premium 3/4 in MDF throughout.

V-Groove and Dado Joinery

CNC cut V-grooves at every panel intersection, sides and divider seated in dados.

Double-Layer 1.5" Front Baffle

Two bonded 3/4 in MDF sheets at the driver face.

Pre-Wired Terminal Cup

Proline X ABS and carbon fiber composite, 12 gauge OFC pre-wired to both driver positions.

Wiring the One Audio RSq3 Pair to Your Amplifier

The RSq3 ships as a dual 1 ohm or a dual 2 ohm, and the impedance maths on this driver deserves care. A single dual 1 ohm gives 2 ohms in series or 0.5 ohms in parallel, which almost nothing on the market is stable into. A single dual 2 ohm gives 4 ohms in series or 1 ohm in parallel.

With two drivers there are more combinations and most of them are very low. On a pair of dual 1 ohm coils, all four in parallel is 0.25 ohms, which is not a load, it is a short as far as most amplifiers are concerned. Sensible targets are 1 ohm or 2 ohms on the dual 1 ohm pair and 2 ohms or 4 ohms on the dual 2 ohm pair. Work the wiring out before you buy the amplifier, not after.

Built in Tennessee, Backed by Audio Intensity

Cut and assembled in Tullahoma, Tennessee on our own CNC equipment. Finished in plush black carpet. 1 year limited warranty. Enclosure only, the One Audio RSq3 drivers are purchased separately. Call or text 931-563-5151.

One Audio RSq3 Dual: Well Damped in a Rear-Firing Wedge

1.20 cubic feet net per driver at Qtc 0.65 to 0.68, cut direct fit and built to order in Tennessee.

Specifications

Specification	Value
Series	Proline X Performance Optimized Wedge
Compatible Driver	One Audio RSq3, quantity 2. Direct fit, either coil version
Configuration	Dual 12 inch, dual chamber sealed wedge
Mounting Position	Trunk or cargo area, tall face against the rear seat back
Firing Direction	Rearward into the trunk. Not a down fire design, no feet included
External Width	32.00 in
External Height	16 in at the seat face
External Depth	17.77 in at the base, tapering to 11.94 in at the top
Internal Volume, Gross	2.86 cu ft total, 1.43 per chamber
Internal Volume, Net Acoustic	2.40 cu ft total, 1.20 per driver after 0.23 displacement each
Published Target	1.20 cu ft net sealed
Alignment, RSq3 D1	Qtc 0.679, fc 38.0 Hz, F3 39.6 Hz anechoic (dual 1 ohm)
Alignment, RSq3 D2	Qtc 0.649, fc 37.2 Hz, F3 40.8 Hz anechoic (dual 2 ohm)
Woofer Opening	11.125 in (283 mm) direct fit, both positions
Driver Mounting Depth	8.50 in required
Driver Frame Diameter	12.625 in
Driver Displacement	0.23 cu ft each, unusually large for a 12 in
Driver Power Handling	1500 W each
Driver Xmax	32 mm as published, basis not stated
Wiring Options	D1: 2 ohms series, 0.5 ohms parallel. D2: 4 ohms series, 1 ohm parallel
Material	Langboard Elite MDF
Construction	CNC cut, V-groove and dado joinery
Panel Thickness	0.75 in
Front Baffle	1.5 in, double baffle
Internal Bracing	Full chamber divider
Driver Mounting	Threaded inserts at every mounting location, stainless machine screws included
Terminal Cups	One Proline X ABS and carbon fiber composite, side mounted, pre wired 12 gauge OFC
Damping	Light polyfill wall lining, does not alter acoustic volume
Carpet	Plush black
Weight	56 lb
Warranty	1 Year Limited
Built In	Tullahoma, Tennessee

Performance Graphs

Net airspace

1.20

cu ft per chamber

System Qtc

0.65–0.68

sealed

Half power

39.6–40.8

Hz · F3

Xmax at

1955

W RMS · no filter

With 25 Hz subsonic

3187

W RMS · +63%

Amplifier

1500

W RMS recommended

This enclosure holds 1.20 cu ft net per chamber. In it the One Audio RSq3 runs a system Qtc of 0.65–0.68 with half power at 39.6–40.8 Hz, and the cone reaches its 32.0 mm travel limit at 1955 W, above the driver’s 1500 W thermal rating, so heat stops you before travel does. Run a subsonic filter at 25 Hz and that becomes 3187 W — +1232 W, or 63 percent more power for the same 32.0 mm of travel.

01Is it a sealed driver?

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

EBP = Fs ÷ Qes = 49.6–50.6

RSq3 D1 · EBP 49.6RSq3 D2 · EBP 50.6

The RSq3 straddles the boundary at 49.6–50.6 depending on coil — part sealed-band, part transition. Either way it takes a sealed load happily; the coil you run shifts the alignment more than it shifts this verdict.

02What the box does to it

1.20 cu ft against a 37.0 L Vas.

α = Vas ÷ Vb = 1.09 · Fc = Fs√(α+1) = 37–38 Hz · Qtc = 0.65–0.68

RSq3 D1 · Qtc 0.68, Fc 38 Hz, F3 39.6 HzRSq3 D2 · Qtc 0.65, Fc 37 Hz, F3 40.8 Hz

The box lifts resonance from 25.8–26.3 Hz free-air to 37–38 Hz and half power lands at 39.6–40.8 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 32.0 mm — and a bigger one once a subsonic filter stops it wasting travel below the passband.

P_Xmax = 1955–1956 W unfiltered → 3187–3362 W with a 25 Hz subsonic

RSq3 D1 · 1955 W, no filterRSq3 D2 · 1956 W, no filterRSq3 D1 · 3187 W with subsonic at 25 Hz, 24 dB/octRSq3 D2 · 3362 W with subsonic at 25 Hz, 24 dB/octXmax 32.0 mm one-way

Every trace touches the limit and no further, because each is drawn at the exact power that puts that coil on 32.0 mm. Unfiltered that is 1955 W, reached first at 20 Hz. It sits above the 1500 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 3187 W before hitting the same 32.0 mm. That is 63 percent more amplifier for the price of one filter setting.

Param	Value	Unit	Note
Fs	26.30 / 25.80	Hz	free-air resonance
Qts	0.470 / 0.450		RSq3 D1 / RSq3 D2
Vas	37.01 / 36.78	L	equivalent compliance
Sd	480.0	cm²	effective piston area
Xmax	32	mm	published without a stated basis
Pe	1500	W	continuous RMS
SPL	82.9	dB	1 W / 1 m, derived from T/S

Driver parameters as published by oneaudiousa.com. 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

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.