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Performance Optimized · Datasheet

Performance Optimized Wedge Enclosure | Fits Dual Kicker Solo X 12" Subwoofers Dual 12" Sealed enclosure

Net volume
1.13 Cubic Feet
Max mounting depth
10-1/8 Inches, Cleared With Margin
Cutout
11-1/16 Inches (Kicker Spec)
External dimensions
31.75 Inches W × 15.25 Inches H × 11.75 Inches / 17.25 Inches D
Front baffle
Double-Layer 1.5" MDF Plus Trim Layer
Buy at Audio Intensity
  • Alignment: Two identical sealed chambers, 1.13 cu ft net each (2.26 total), tightly damped. Dual 1-ohm 49L7X121s run Qtc 0.61, F3 59.8 Hz; dual 2-ohm 49L7X122s run Qtc 0.64, F3 58.8 Hz per chamber
  • Chambers: Full-height 3/4 in dado-locked divider, one driver per chamber, doubles as bracing across the 31.75 in span
  • Drivers: Pair of Kicker Solo X L7X 12s, matched coil versions. Each opening CNC-cut to 11-1/16 in per Kicker spec, 10-1/8 in depth cleared
  • Wiring: One shared side-mounted terminal cup, 12 gauge OFC to both positions. Kicker recommends 1000-2000 watts RMS per driver, 2000-4000 system
  • Cabinet: 31.75 in W x 15.25 in H x 11.75/17.25 in D, 3/4 in Langboard Elite MDF, 1.5 in double baffle plus trim, plush black carpet with black acrylic insert

Technical specifications

SeriesProline X Performance Optimized Wedge
Compatible DriverKicker Solo X L7X 12 (49L7X121 / 49L7X122) | Pair Required
Enclosure TypeSealed | Dual Driver | Front-Firing Wedge
Chamber ConfigurationTwo Identical Sealed Chambers | Full 3/4" Divider | Single Shared Side-Mounted Terminal Cup
Wedge Angle20 Degrees, Vertical Rear Panel
External Width31.75 Inches
External Height15.25 Inches
External Depth (Top)11.75 Inches
External Depth (Bottom)17.25 Inches
Total Internal Gross Volume2.66 Cubic Feet
Per-Chamber Net Volume1.13 Cubic Feet
Total Net Volume2.26 Cubic Feet
System Qtc Per Chamber (Dual 1-Ohm)0.61 Tightly Damped
System Qtc Per Chamber (Dual 2-Ohm)0.64 Tightly Damped
Predicted Fc Per Driver50 Hz (D1) / 52 Hz (D2)
Predicted F3 Per Driver (Anechoic)59.8 Hz (D1) / 58.8 Hz (D2)
Driver Fs (D1 / D2)40.3 Hz / 41.6 Hz (Kicker Factory)
Driver Qts (D1 / D2)0.487 / 0.506 (Kicker Factory)
Driver Vas (D1 / D2)18.05 L / 18.36 L (Kicker Factory)
Woofer Cutout (Each)11-1/16 Inches (Kicker Spec)
Mounting Depth Required (Each)10-1/8 Inches, Cleared With Margin
Recommended Power Per Driver1000-2000 Watts RMS (Kicker Recommendation)
Recommended System Power2000-4000 Watts RMS Across The Pair
MaterialLangboard Elite 3/4" MDF
ConstructionShopSabre CNC | V-Groove and Dado Joinery
Panel Thickness3/4 Inch
Front BaffleDouble-Layer 1.5" MDF Plus Trim Layer
Chamber Divider3/4" MDF Full-Height, Dado-Locked, Doubles As Brace
Driver Mounting8/32 Threaded Inserts | Stainless Machine Screws Included | 2 Sets
Terminal CupOne Proline X ABS/Carbon Fiber Composite | Side Mounted | Serves Both Chambers
Internal Wiring12 Gauge OFC, Pre-Wired To Both Driver Positions
FinishPlush Black Carpet | Black Acrylic Insert
Bundle OptionsEnclosure Only (Bring Your Own Pair of Solo X 12s)
Warranty1-Year Limited (Enclosure)
Built InTullahoma, Tennessee, USA

Performance in this enclosure

Net airspace
1.13
cu ft per chamber
System Qtc
0.61–0.63
sealed
Half power
58.8–59.8
Hz · F3
Xmax at
4802
W RMS · no filter
With 25 Hz subsonic
6874
W RMS · +43%
Amplifier
1000–2000
W RMS recommended
This enclosure holds 1.13 cu ft net per chamber. In it the Kicker SoloX L7X 12 (49L7X121) runs a system Qtc of 0.61–0.63 with half power at 58.8–59.8 Hz, and the cone reaches its 31.25 mm travel limit at 4802 W, above the driver’s 2000 W thermal rating, so heat stops you before travel does. Run a subsonic filter at 25 Hz and that becomes 6874 W — +2072 W, or 43 percent more power for the same 31.25 mm of travel.

01Is it a sealed driver?

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

EBP = Fs ÷ Qes = 76.5–78.2
SEALED 0–50 TRANSITION 50–100 PORTED 100–150 0 50 100 150 D1 78.2 D2 76.5
D1 · EBP 78.2D2 · EBP 76.5
At 76.5–78.2 the SoloX L7X 12 (49L7X121) 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

1.13 cu ft against a 18.0 L Vas.

α = Vas ÷ Vb = 0.56  ·  Fc = Fs√(α+1) = 50–52 Hz  ·  Qtc = 0.61–0.63
20 30 50 70 100 150 200 +6 +0 -6 -12 -18 -24 FREQUENCY · Hz LEVEL · dB −3 dB
D1 · Qtc 0.61, Fc 50 Hz, F3 59.8 HzD2 · Qtc 0.63, Fc 52 Hz, F3 58.8 Hz
The box lifts resonance from 40.3–41.6 Hz free-air to 50–52 Hz and half power lands at 58.8–59.8 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 31.25 mm — and a bigger one once a subsonic filter stops it wasting travel below the passband.

PXmax = 4802–5009 W unfiltered  →  6874–6949 W with a 25 Hz subsonic
20 30 50 70 100 150 200 0 8 16 24 32 FREQUENCY · Hz CONE TRAVEL · mm PAST LINEAR TRAVEL · Xmax 31.25 mm 4802 W reaches Xmax here
D1 · 4802 W, no filterD2 · 5009 W, no filterD1 · 6949 W with subsonic at 25 Hz, 24 dB/octD2 · 6874 W with subsonic at 25 Hz, 24 dB/octXmax 31.25 mm one-way
Every trace touches the limit and no further, because each is drawn at the exact power that puts that coil on 31.25 mm. Unfiltered that is 4802 W, reached first at 20 Hz. It sits above the 2000 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 6874 W before hitting the same 31.25 mm. That is 43 percent more amplifier for the price of one filter setting.
ParamValueUnitNote
Fs40.30 / 41.60Hzfree-air resonance
Qts0.487 / 0.506D1 / D2
Vas18.05 / 18.36Lequivalent compliance
Sd585.6cm²effective piston area
Xmax31.25mmone-way linear travel
Pe2000Wcontinuous RMS
SPL85.5dB1 W / 1 m, derived from T/S

Driver parameters as published by Kicker published Klippel T/S sheet. Curves computed against this enclosure’s actual net airspace.

Installer's take

This is the output king of the sealed wedge line. Two Solo X 12s, each in its own 1.13 cubic foot chamber at the same tightly damped 0.61-0.64 Qtc as the single 12, deliver the most cone area and the most displacement of any box we build in this series. Same flat, controlled character as the single, roughly 6 dB more of it, and the authority to make sealed bass feel effortless at any volume.

The full-height divider earns its keep twice here. Sonically it keeps each 12 in its own air so neither modulates the other's alignment. Structurally it bisects a 31.75 inch cabinet at exactly the span where big cone area would otherwise start talking through the panels. Two drivers at up to 2000 watts each will find any weakness; this box does not offer one.

Matched coils, identical wiring, one shared cup. A dual 1-ohm pair lands at 1 or 4 ohms in the common configurations, a dual 2-ohm pair at 0.5 or 2 ohms; map your amplifier's rated load first, then order drivers. Feed the pair 2000-4000 clean watts and set gains properly; the sealed chambers keep both cones loaded and composed at full output.

Measure twice on this one. You need 31.75 inches of clear width, 15.25 of height, and 17.25 of floor depth. In most crew cabs it fits centered behind the seat; in anything smaller, confirm the span between belt towers. If it fits, nothing else in this line touches it for sheer capability.

Questions

Will my Kicker Solo X 12s fit this enclosure?

Yes. Each baffle opening is CNC-cut to Kicker's published 11-1/16 inch cutout for the Solo X L7X 12, and each chamber clears the required 10-1/8 inch mounting depth with margin, including breathing room for the vented motors. Both coil versions fit; just use a matched pair.

Why two separate chambers instead of one shared volume?

Because two drivers sharing one volume stop behaving like the alignment says they should. Each cone's compression stroke becomes the other's pressure environment, which smears transients and blurs the Qtc both were designed to hit. The full-height 3/4 inch divider gives each Solo X 12 its own 1.13 cubic feet at the same tightly damped tune as our single 12, keeps the pair perfectly matched, and braces the widest span of the cabinet as a bonus.

Do both subwoofers need to be the same coil version?

Yes. Run two dual 1-ohm drivers or two dual 2-ohm drivers, never one of each. Identical drivers wired identically off the shared cup share power evenly and move in lockstep; mixed coils create unequal branch impedances that unbalance the pair. A dual 1-ohm pair commonly wires to 1 or 4 ohms, a dual 2-ohm pair to 0.5 or 2 ohms; choose whichever lands on your amplifier's rated load.

How much power should I run to a pair of Solo X 12s?

Kicker recommends 1000-2000 watts RMS per Solo X 12, so plan 2000-4000 watts RMS of clean power across the pair at your wired impedance. The tightly damped chambers keep both cones loaded through the passband, which makes the top of that range genuinely usable with properly set gains. One high-current monoblock into the shared cup is the standard recipe.

How does the dual 12 compare to the single 18 wedge?

The dual 12s bring more total cone area and about 3 dB more thermal capability, in a cabinet 3 inches shorter than the 18's. The 18 counters with reach: its Fc sits down near 40 Hz, the deepest sealed tune in the line, and one giant cone has a scale to its presentation that multiple smaller drivers never quite copy. Chasing maximum clean output behind a seat, take the dual 12s. Chasing the deepest, most effortless bottom octave, take the 18. Neither answer is wrong.

Will this wedge fit behind the seat of my truck?

You need 31.75 inches of width, 15.25 inches of height, and 17.25 inches of depth at the floor; the top needs only 11.75 inches thanks to the 20 degree baffle rake, and the vertical rear panel sits flat against the cab wall. This is a crew-cab-class footprint. Measure the clear span behind your seat between belt towers and door trim, and check height against the seat back, before ordering.

Are the subwoofers included with this enclosure?

No, this listing is the enclosure only. It is built for a matched pair of Kicker Solo X L7X 12s, which you install using the pressed 8/32 threaded inserts and the two sets of included stainless mounting hardware. If you want help sourcing a pair of Solo X 12s or matching an amplifier, call us at 931-563-5151.

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