Proline X PO 12D-S W JL W3V3 dual sealed wedge enclosure, product photos pending. Placeholder graphic reading Photos Coming Soon.

Performance Optimized · Datasheet

Performance Optimized Wedge Sealed Dual 12" Enclosure | JL Audio 12W3v3 Dual 12" Sealed enclosure

Net volume
2.50 cu ft total, 1.250 cu ft per driver after 0.071 displacement
Max mounting depth
9.79 in
External dimensions
32.00 in W × 16 in at the seat face H × 16.86 in at the base D
Front baffle
1.5 in, double baffle
Buy at Audio Intensity
  • Driver: JL Audio 12W3v3 x2, direct fit only
  • Net Acoustic: 1.250 cu ft per driver, JL target 1.250
  • Alignment: Qtc 0.796 to 0.901, F3 41.8 to 43.5 Hz
  • Chambers: Dual, full divider
  • Position: Trunk mount, tall face against rear seat
  • Firing: Rearward. No down fire option
  • Footprint: 32.00 in W x 16.86 in D at the base
  • Weight: 54 lb

Technical specifications

SpecificationValue
SeriesProline X Performance Optimized Wedge
Compatible DriverJL Audio 12W3v3, quantity 2. Direct fit, no other driver
ConfigurationDual 12 inch, dual chamber sealed wedge
Mounting PositionTrunk or cargo area, tall face against the rear seat back
Firing DirectionRearward into the trunk. Not a down fire design, no feet included
External Width32.00 in
External Height16 in at the seat face
External Depth16.86 in at the base, tapering to 11.04 in at the top
Internal Volume, Gross2.642 cu ft total, 1.321 cu ft per chamber
Internal Volume, Net Acoustic2.50 cu ft total, 1.250 cu ft per driver after 0.071 displacement
JL Published Target1.25 cubic feet, JL's published figure for the 12W3v3-2
Alignment, 12W3v3-4Qtc 0.796, fc 48.3 Hz, F3 43.5 Hz anechoic
Alignment, 12W3v3-2Qtc 0.901, fc 50.4 Hz, F3 41.8 Hz anechoic
Woofer Opening281mm direct fit, both positions
Max Mounting Depth9.79 in
Driver Power Handling500 W RMS each, 1000 W combined
MaterialLangboard Elite MDF
ConstructionCNC cut, dado and V groove joinery
Panel Thickness0.75 in
Front Baffle1.5 in, double baffle
Chamber DividerFull divider, no shared airspace
Driver MountingThreaded inserts at every driver mounting location, stainless machine screws included
Terminal CupsOne Proline X ABS and carbon fiber composite, side mounted, pre wired 12 gauge OFC to both driver positions
DampingLight polyfill wall lining, does not alter acoustic volume
CarpetPlush black
BadgeWoofer face mounted, black lasered acrylic
Weight54 lb
Warranty1 Year Limited
Built InTullahoma, Tennessee

Performance in this enclosure

Net airspace
1.25
cu ft per chamber
System Qtc
0.80–0.90
sealed
Half power
41.8–43.5
Hz · F3
Xmax at
328
W RMS · no filter
With 25 Hz subsonic
369
W RMS · +13%
Amplifier
500
W RMS recommended
This enclosure holds 1.25 cu ft net per chamber. In it the JL Audio 12W3v3 runs a system Qtc of 0.80–0.90 with half power at 41.8–43.5 Hz, and the cone reaches its 13.0 mm travel limit at 328 W, below the driver’s 500 W thermal rating, so travel is what stops you here, not heat. Run a subsonic filter at 25 Hz and that becomes 369 W — +41 W, or 13 percent more power for the same 13.0 mm of travel.

01Is it a sealed driver?

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

EBP = Fs ÷ Qes = 52.8–56.8
SEALED 0–50 TRANSITION 50–100 PORTED 100–150 0 50 100 150 12W3v3-2 52.8 12W3v3-4 56.8
12W3v3-2 · EBP 52.812W3v3-4 · EBP 56.8
At 52.8–56.8 the 12W3v3 sits in the transition band, not the sealed band. That is not a mismatch: a transition motor works in either alignment, and sealed buys a smaller box and a gentler roll-off at the cost of some low-end output. Stage 02 shows what this airspace actually does with it.

02What the box does to it

1.25 cu ft against a 79.5 L Vas.

α = Vas ÷ Vb = 2.25  ·  Fc = Fs√(α+1) = 48–50 Hz  ·  Qtc = 0.80–0.90
20 30 50 70 100 150 200 +6 +0 -6 -12 -18 -24 FREQUENCY · Hz LEVEL · dB −3 dB
12W3v3-2 · Qtc 0.90, Fc 50 Hz, F3 41.8 Hz12W3v3-4 · Qtc 0.80, Fc 48 Hz, F3 43.5 Hz
The box lifts resonance from 26.7–28.0 Hz free-air to 48–50 Hz and half power lands at 41.8–43.5 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 13.0 mm — and a bigger one once a subsonic filter stops it wasting travel below the passband.

PXmax = 328–344 W unfiltered  →  369–385 W with a 25 Hz subsonic
20 30 50 70 100 150 200 0 4 8 12 16 FREQUENCY · Hz CONE TRAVEL · mm PAST LINEAR TRAVEL · Xmax 13.0 mm 328 W reaches Xmax here
12W3v3-2 · 344 W, no filter12W3v3-4 · 328 W, no filter12W3v3-2 · 369 W with subsonic at 25 Hz, 24 dB/oct12W3v3-4 · 385 W with subsonic at 25 Hz, 24 dB/octXmax 13.0 mm one-way
Every trace touches the limit and no further, because each is drawn at the exact power that puts that coil on 13.0 mm. Unfiltered that is 328 W, reached first at 22 Hz. It sits under the 500 W the driver can take thermally, so the enclosure sets the ceiling, not the voice coil. 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 369 W before hitting the same 13.0 mm. That is 13 percent more amplifier for the price of one filter setting.
ParamValueUnitNote
Fs28.00 / 26.70Hzfree-air resonance
Qts0.500 / 0.44012W3v3-2 / 12W3v3-4
Vas79.50 / 80.50Lequivalent compliance
Sd520.0cm²effective piston area
Xmax13mmone-way linear travel
Pe500Wcontinuous RMS
SPL87.0dB1 W / 1 m, derived from T/S

Driver parameters as published by loudspeakerdatabase.com. Curves computed against this enclosure’s actual net airspace.

Installer's take

Wire the terminal cup before you set this box in the trunk. Once the tall face is against the seat back there is no getting behind it, and on a wedge you cannot tip it forward to reach the cup. Land it, test continuity, then position.

Confirm both drivers are moving in the same direction before the box goes in. It is a thirty second check with a battery and it is the difference between finding a reversed pair now and pulling the box back out later wondering where the bottom end went.

Measure the base depth, not the top. The cabinet is 16.86 inches deep at the trunk floor and 11.04 at the top, and it is 32.00 wide. The floor dimension is what decides whether it goes in.

Each chamber is 1.321 gross and the 12W3v3 displaces 0.071, which puts every driver at 1.250 net. Check which coil you have before you quote a customer a number: the 12W3v3-4 lands at Qtc 0.796 in this box and the 12W3v3-2 at 0.901. Same cabinet, two different alignments, because they are two different motors.

Both coils are single voice coil. A pair of 2 ohm drivers parallels to 1 ohm, which a lot of amplifiers will not survive. Series for 4 ohms is the safe answer unless the amplifier is explicitly rated for it.

Questions

Can this enclosure be run down firing?

No. This is a rear firing wedge and it has one working orientation: the tall face flat against the rear seat back, taper running out toward the trunk lid. There are no feet and no baffle standoff, so laying it on its face leaves the cones with nowhere to breathe.

If you need a down firing cabinet for the 12W3v3, that is a different Proline X product and a different set of dimensions.

Will a standard 12 inch subwoofer fit this enclosure?

No. The baffle is cut direct fit at 281mm for the JL Audio 12W3v3 and the chamber volume is built to that driver's published requirement. A generic 12 has a different frame diameter, a different mounting depth and a different Vas.

Even where a different driver physically dropped in, it would be seeing an airspace engineered for something else, and the alignment printed on this page would no longer describe what you own.

Why is the gross volume 1.321 cubic feet per chamber but the net acoustic figure lower?

Gross is the empty chamber. Net acoustic is what the driver actually loads against once the driver's own body is sitting in that space. The 12W3v3 displaces 0.071 cubic feet, so a 1.321 gross chamber presents 1.250 net.

Net is the number that decides the alignment, so net is the number the chamber is designed to. Gross is simply what it had to be built at to get there.

Why not build a bigger box for more low end?

A bigger sealed box lowers Qtc and lowers fc, but it does not buy much extension on this driver, and past a point it costs you control. This cabinet sits on the volume JL themselves publish for the 12W3v3.

In a car the cabin does more for the bottom octave than another half cubic foot of box ever will. Building to the published number keeps the driver operating where its designer intended and leaves the cabin to do the rest.

Is this a common chamber or dual chamber enclosure?

Dual chamber, with a full divider running floor to ceiling and front to back. Each 12W3v3 gets its own sealed 1.321 cubic foot chamber and neither driver shares air with the other.

That matters under hard excursion. In a common chamber one cone's motion changes the air load the other cone sees, which makes the pair less predictable exactly when they are working hardest.

Why does a dual enclosure have only one terminal cup?

One cup is the standard across the Proline X wedge range and it is not related to how many chambers the cabinet has. A second cup gets added only when the driver's power rating makes splitting the load across two terminal sets the safer choice under sustained output.

The 12W3v3 at 500 watts RMS each does not need it. This is an enclosure only product, so how the drivers are wired from the cup is left entirely to the installer.

How do I wire two 12W3v3 to my amplifier?

Both W3v3 coils are single voice coil, so a matched pair gives you two options and nothing in between. Two 4 ohm drivers give 2 ohms in parallel or 8 ohms in series. Two 2 ohm drivers give 1 ohm in parallel or 4 ohms in series.

The 1 ohm parallel load is the one to be careful with. Many amplifiers are not stable at 1 ohm and running one there is how amplifiers die. If you are on a pair of 2 ohm drivers, wire them in series for 4 ohms unless your amplifier is explicitly rated 1 ohm stable.

Does this include the JL Audio 12W3v3 subwoofers?

No. This is an enclosure only. You receive the cabinet, carpeted and finished, with threaded inserts installed at both driver positions, stainless machine screws, one pre wired terminal cup and the polyfill lining already in place.

The two 12W3v3 drivers are purchased separately. The cabinet is cut direct fit to that driver, so it is not a general purpose 12 inch box.

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