Performance Optimized · Datasheet

Performance Optimized Wedge Enclosure | Fits Kicker Solo X 18" Subwoofer Single 18" Sealed enclosure

Net volume
4.01 Cubic Feet
Max mounting depth
11-3/8 Inches, Cleared With Margin
Cutout
CNC-Cut To Kicker Published Spec
External dimensions
27 Inches W × 21.25 Inches H × 14.25 Inches / 22 Inches D
Front baffle
Double-Layer 1.5" MDF Plus Trim Layer
Buy at Audio Intensity
  • Alignment: 4.01 cu ft net, the biggest sealed wedge we build. Dual 1-ohm 49L7X181 runs Qtc 0.81, Fc 39.1 Hz, F3 34.7 Hz; dual 2-ohm 49L7X182 runs Qtc 0.90, Fc 40.9 Hz, F3 34.0 Hz. Deepest sealed tune in the Solo X line
  • Geometry: 20° front-firing wedge, vertical rear panel. 27 in W x 21.25 in H x 14.25 in top / 22 in bottom depth
  • Driver: Kicker Solo X L7X 18 (either coil version). Baffle CNC-cut to Kicker's published cutout spec, 11-3/8 in mounting depth cleared with margin
  • Wiring: One side-mounted terminal cup, 12 gauge OFC pre-wired. Handles up to 4000 watts RMS; set final impedance at the driver's coils
  • Cabinet: 3/4 in Langboard Elite MDF, 1.5 in double-layer baffle plus trim, dado-locked brace behind the woofer, plush black carpet with black acrylic insert

Technical specifications

SeriesProline X Performance Optimized Wedge
Compatible DriverKicker Solo X L7X 18 (49L7X181 Dual 1-Ohm / 49L7X182 Dual 2-Ohm)
Enclosure TypeSealed | Single Driver | Front-Firing Wedge
Wedge Angle20 Degrees, Vertical Rear Panel
External Width27 Inches
External Height21.25 Inches
External Depth (Top)14.25 Inches
External Depth (Bottom)22 Inches
Internal Gross Volume4.30 Cubic Feet
Net Volume (After Driver Displacement)4.01 Cubic Feet
System Qtc (Dual 1-Ohm)0.81 (Computed from Kicker Factory T/S)
System Qtc (Dual 2-Ohm)0.90 (Computed from Kicker Factory T/S)
Predicted Fc39.1 Hz (D1) / 40.9 Hz (D2)
Predicted F3 (Anechoic)34.7 Hz (D1) / 34.0 Hz (D2)
Driver Fs (D1 / D2)26.9 Hz / 28.9 Hz (Kicker Factory)
Driver Qts (D1 / D2)0.5575 / 0.6345 (Kicker Factory)
Driver Vas (D1 / D2)125.93 L / 113.95 L (Kicker Factory)
Woofer CutoutCNC-Cut To Kicker Published Spec
Mounting Depth Required11-3/8 Inches, Cleared With Margin
Power HandlingUp To 4000 Watts RMS
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
Internal Bracing3/4" Dado-Locked Brace Behind Woofer
Driver Mounting8/32 Threaded Inserts | Stainless Machine Screws Included
Terminal CupOne Proline X ABS/Carbon Fiber Composite | Side Mounted
Internal Wiring12 Gauge OFC, Pre-Wired
FinishPlush Black Carpet | Black Acrylic Insert
Bundle OptionsEnclosure Only (Bring Your Own Solo X 18)
Warranty1-Year Limited (Enclosure)
Built InTullahoma, Tennessee, USA

Performance in this enclosure

Net airspace
4.01
cu ft per chamber
System Qtc
0.81–0.90
sealed
Half power
34.0–34.7
Hz · F3
Xmax at
4710
W RMS · no filter
With 25 Hz subsonic
6383
W RMS · +36%
Amplifier
1000–2000
W RMS recommended
This enclosure holds 4.01 cu ft net per chamber. In it the Kicker SoloX L7X 18 (49L7X181) runs a system Qtc of 0.81–0.90 with half power at 34.0–34.7 Hz, and the cone reaches its 31.25 mm travel limit at 4710 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 6383 W — +1673 W, or 36 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 = 41.1–44.4
SEALED 0–50 TRANSITION 50–100 PORTED 100–150 0 50 100 150 D1 44.4 D2 41.1
D1 · EBP 44.4D2 · EBP 41.1
EBP under 50 means a motor that wants a sealed load. The SoloX L7X 18 (49L7X181) sits at 41.1–44.4, inside that band, which is why this is a sealed build rather than a ported one.

02What the box does to it

4.01 cu ft against a 125.9 L Vas.

α = Vas ÷ Vb = 1.11  ·  Fc = Fs√(α+1) = 39–41 Hz  ·  Qtc = 0.81–0.90
20 30 50 70 100 150 200 +6 +0 -6 -12 -18 -24 FREQUENCY · Hz LEVEL · dB −3 dB
D1 · Qtc 0.81, Fc 39 Hz, F3 34.7 HzD2 · Qtc 0.90, Fc 41 Hz, F3 34.0 Hz
The box lifts resonance from 26.9–28.9 Hz free-air to 39–41 Hz and half power lands at 34.0–34.7 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 = 4710–5304 W unfiltered  →  6383–6428 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 4710 W reaches Xmax here
D1 · 4710 W, no filterD2 · 5304 W, no filterD1 · 6428 W with subsonic at 25 Hz, 24 dB/octD2 · 6383 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 4710 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 6383 W before hitting the same 31.25 mm. That is 36 percent more amplifier for the price of one filter setting.
ParamValueUnitNote
Fs26.90 / 28.90Hzfree-air resonance
Qts0.557 / 0.634D1 / D2
Vas125.93 / 113.95Lequivalent compliance
Sd1406.2cm²effective piston area
Xmax31.25mmone-way linear travel
Pe2000Wcontinuous RMS
SPL87.9dB1 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 deep-end of the line, in every sense. Four cubic feet net puts the Solo X 18's system resonance down at 39-41 Hz with an anechoic F3 in the mid 30s, before the cab helps. No other box in our sealed wedge family reaches close to that. Add typical truck cabin gain and you have genuine single-digit-teens extension with a cone the size of a manhole cover doing it without strain.

The Qtc runs 0.81 on the dual 1-ohm and 0.90 on the dual 2-ohm, higher than our smaller wedges, and that is physics rather than choice: an 18 with 126 liters of Vas would need a refrigerator to hit 0.707. What the slightly higher Q costs in critical damping it pays back in warmth and impact, and the mild rise near resonance sits low enough that it reads as weight, not boom.

Feed it seriously. The 18 will take up to 4000 watts, and in sealed air the cone stays loaded across the whole stroke, so big clean power translates directly into effortless output. Pick coils for your amplifier as always: dual 1-ohm for 0.5 or 2 ohm finals, dual 2-ohm for 1 or 4.

Respect the tape measure. 27 wide, 21.25 tall, 22 deep at the floor. This is a full-size crew cab or SUV cargo proposition, and the 21.25 inch height is the number that disqualifies most standard cabs. If it fits your space, nothing else we build in a sealed box sounds this big.

Questions

Will my Kicker Solo X 18 fit this enclosure?

Yes. The baffle is CNC-cut to Kicker's published cutout spec for the Solo X L7X 18, and the cabinet clears the required 11-3/8 inch mounting depth with margin at every point of the stroke, including breathing room for the vented motor. Both the dual 1-ohm 49L7X181 and dual 2-ohm 49L7X182 fit identically.

How deep does the Solo X 18 actually play in this box?

Deeper than any other box in this line. The system resonance sits at 39.1 Hz for the dual 1-ohm and 40.9 Hz for the dual 2-ohm, with anechoic F3s of 34.7 and 34.0 Hz, and that is before the vehicle helps. Cabin gain in a truck or SUV typically adds output at a rising rate below 60 Hz, which carries usable response well down into the 20s. Pipe-organ and sub-synth content that smaller sealed boxes only hint at is fully present here.

Which coil version should I buy, dual 1-ohm or dual 2-ohm?

Choose by amplifier first. The dual 1-ohm lands at Qtc 0.81 and the dual 2-ohm at 0.90 in this airspace; the D1 is slightly better damped, the D2 slightly warmer, and both reach the same mid-30s F3. Those are shadings, not different characters. What matters more is that your amplifier makes its rated power at the load your wiring produces: dual 1-ohm wires to 0.5 or 2 ohms, dual 2-ohm to 1 or 4.

How much power should I run to the Solo X 18 in this box?

The Solo X 18 handles up to 4000 watts RMS and this cabinet is built to let it use that: the sealed air spring loads the cone progressively through the stroke and the 1.5 inch double baffle takes the mechanical load without flexing. Anything from 2000 watts up wakes it fully. As always, clean power with gains set by scope or DMM beats raw wattage, and the sealed loading is forgiving of the occasional hard transient.

Why is the Qtc higher on the 18 than on your other wedges?

Because the driver is enormous. Qtc is set by the ratio of a driver's Vas to the box volume, and the Solo X 18's Vas is around 126 liters; reaching 0.707 would take a cabinet far too large to stand behind any seat. At 4.01 net cubic feet, already the biggest wedge we build, the alignment lands at 0.81 to 0.90 depending on coils. That range trades a little critical damping for weight and impact, and because Fc sits down near 40 Hz, the mild rise reads as low-end authority rather than midbass boom.

Will this wedge actually fit behind a truck seat?

Only in the biggest cabs, and you should measure before ordering. You need 27 inches of width, 21.25 inches of height, and 22 inches of depth at the floor, tapering to 14.25 at the top. Height is the gatekeeper; most standard and extended cabs will not clear 21.25 inches behind the seat. Full-size crew cabs with the seat bottom flipped, SUV cargo areas, and rear-wall van installs are this box's natural habitat.

Is the subwoofer included with this enclosure?

No, this listing is the enclosure only. It is built specifically for the Kicker Solo X L7X 18 in either coil configuration, and you install your own driver using the pressed 8/32 threaded inserts and included stainless mounting hardware. If you want help pairing a Solo X 18 or an amplifier capable of feeding it, call us at 931-563-5151.