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Performance Optimized · Datasheet

Performance Optimized Wedge Enclosure | Fits Kicker Solo X 15" Subwoofer Single 15" Sealed enclosure

Net volume
2.76 Cubic Feet
Max mounting depth
11.5625 Inches, Cleared With Margin
Cutout
13.75 Inches (Kicker Spec)
External dimensions
26 Inches W × 18.25 Inches H × 12.625 Inches / 19.25 Inches D
Front baffle
Double-Layer 1.5" MDF Plus Trim Layer
Buy at Audio Intensity
  • Alignment: 2.76 cu ft net in a sealed wedge. Dual 1-ohm 49L7X151 lands at Qtc 0.707 (true Butterworth), Fc 45 Hz, F3 45 Hz; dual 2-ohm 49L7X152 runs Qtc 0.79, Fc 46 Hz, F3 41.7 Hz
  • Geometry: 20° front-firing wedge, vertical rear panel sits flat against the cab wall. 26 in W x 18.25 in H x 12.625 in top / 19.25 in bottom depth
  • Driver: Kicker Solo X L7X 15 (either coil version). Baffle CNC-cut to 13.75 in per Kicker spec, 11.5625 in mounting depth cleared with margin
  • Wiring: One side-mounted terminal cup, 12 gauge OFC pre-wired. Kicker recommends 1000-2000 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 15 (49L7X151 Dual 1-Ohm / 49L7X152 Dual 2-Ohm)
Enclosure TypeSealed | Single Driver | Front-Firing Wedge
Wedge Angle20 Degrees, Vertical Rear Panel
External Width26 Inches
External Height18.25 Inches
External Depth (Top)12.625 Inches
External Depth (Bottom)19.25 Inches
Internal Gross Volume3.00 Cubic Feet
Net Volume (After Driver Displacement)2.76 Cubic Feet
System Qtc (Dual 1-Ohm)0.707 Butterworth (Computed from Kicker Factory T/S)
System Qtc (Dual 2-Ohm)0.79 (Computed from Kicker Factory T/S)
Predicted Fc45 Hz (D1) / 46 Hz (D2)
Predicted F3 (Anechoic)45 Hz (D1) / 41.7 Hz (D2)
Woofer Cutout13.75 Inches (Kicker Spec)
Mounting Depth Required11.5625 Inches, Cleared With Margin
Recommended Power1000-2000 Watts RMS (Kicker Recommendation)
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 15)
Warranty1-Year Limited (Enclosure)
Built InTullahoma, Tennessee, USA

Performance in this enclosure

Net airspace
2.76
cu ft per chamber
System Qtc
0.71–0.79
sealed
Half power
41.3–45.0
Hz · F3
Xmax at
5263
W RMS · no filter
With 25 Hz subsonic
6600
W RMS · +25%
Amplifier
1000–2000
W RMS recommended
This enclosure holds 2.76 cu ft net per chamber. In it the Kicker SoloX L7X 15 (49L7X151) runs a system Qtc of 0.71–0.79 with half power at 41.3–45.0 Hz, and the cone reaches its 31.25 mm travel limit at 5263 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 6600 W — +1337 W, or 25 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 = 52.8–59.2
SEALED 0–50 TRANSITION 50–100 PORTED 100–150 0 50 100 150 D1 59.2 D2 52.8
D1 · EBP 59.2D2 · EBP 52.8
At 52.8–59.2 the SoloX L7X 15 (49L7X151) 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

2.76 cu ft against a 42.1 L Vas.

α = Vas ÷ Vb = 0.54  ·  Fc = Fs√(α+1) = 45–46 Hz  ·  Qtc = 0.71–0.79
20 30 50 70 100 150 200 +6 +0 -6 -12 -18 -24 FREQUENCY · Hz LEVEL · dB −3 dB
D1 · Qtc 0.71, Fc 45 Hz, F3 45.0 HzD2 · Qtc 0.79, Fc 46 Hz, F3 41.3 Hz
The box lifts resonance from 36.3–36.4 Hz free-air to 45–46 Hz and half power lands at 41.3–45.0 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 = 5263–5385 W unfiltered  →  6600–7231 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 5263 W reaches Xmax here
D1 · 5263 W, no filterD2 · 5385 W, no filterD1 · 7231 W with subsonic at 25 Hz, 24 dB/octD2 · 6600 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 5263 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 6600 W before hitting the same 31.25 mm. That is 25 percent more amplifier for the price of one filter setting.
ParamValueUnitNote
Fs36.30 / 36.40Hzfree-air resonance
Qts0.570 / 0.631D1 / D2
Vas42.10 / 44.80Lequivalent compliance
Sd961.0cm²effective piston area
Xmax31.25mmone-way linear travel
Pe2000Wcontinuous RMS
SPL87.0dB1 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 Butterworth box of the Solo X wedge line. At 2.76 net cubic feet the dual 1-ohm 15 lands at Qtc 0.707 almost exactly, which is the alignment every sealed-box textbook is written around: flattest possible response with zero peaking and the best transient behavior a closed box can give. The dual 2-ohm runs 0.79 in the same air, a hair warmer through the 50-70 Hz octave. Nobody will pick the difference in a truck cab.

Pick your coil version by your amplifier, not by the box. Both versions load this cabinet correctly, so buy the coils that let your amp see its happiest load: dual 1-ohm for a 1-ohm-stable monoblock wired parallel, dual 2-ohm if you want a 1-ohm or 4-ohm final. The alignment takes care of itself.

Placement is what the wedge shape is for. The rear panel is dead vertical, so it sits flush against the back wall of the cab, and the baffle rakes forward 20 degrees to clear a leaned seat back while firing the cone into the cabin. Measure before you order: you need 26 inches of width, 18.25 of height, and 19.25 of depth at the floor. The top of the box only needs 12.625.

On power, Kicker's recommendation is 1000-2000 watts RMS and the sealed loading is what makes the top of that range usable. The air spring rises fast below Fc, so the cone stays controlled where a ported box would let it unload. Clean power matters more than big power; set gains with a scope or DMM and the 15 will take everything a real 2000-watt amp makes.

Know what you are buying. A ported Solo X build will out-SPL this box, no argument. What this wedge does is play flat, stop on a dime, and disappear behind a seat, and cabin gain hands back most of the bottom octave the anechoic chart gives up. If the goal is musical, accurate low end from the flagship square sub, this is the alignment that does it.

Questions

Will my Kicker Solo X 15 fit this enclosure?

Yes. The baffle is CNC-cut to Kicker's published 13.75 inch cutout for the Solo X L7X 15, and the cabinet clears the required 11.5625 inch mounting depth with margin at every point of the stroke, including breathing room for the vented motor. Both the dual 1-ohm 49L7X151 and dual 2-ohm 49L7X152 fit identically.

What is a Butterworth alignment and why does it matter?

Butterworth describes a sealed system with a total Q of 0.707, the point where the response stays maximally flat all the way to the knee with no peak and no early sag. Below 0.707 a box trades extension for even tighter damping; above it, response picks up a bump around resonance that reads as boom. This cabinet's airspace was solved from Kicker's factory Thiele/Small parameters to land the dual 1-ohm Solo X 15 at 0.707 exactly, so you get the flattest, best-controlled bass the driver can produce in a sealed box.

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

Choose by amplifier, not by the box. In this airspace the dual 1-ohm lands at Qtc 0.707 and the dual 2-ohm at 0.79; both are firmly in the accurate, musical zone and the audible difference in a vehicle is minimal. Buy the coil configuration that wires to the impedance your amplifier makes its rated power into: dual 1-ohm gives you a 0.5 or 2 ohm final, dual 2-ohm gives you 1 or 4 ohms.

How much power should I run to the Solo X 15 in this box?

Kicker recommends 1000-2000 watts RMS for the Solo X 15, and this sealed alignment supports the full range. The sealed air spring keeps cone travel controlled as level rises, so the driver stays composed at power in a way ported boxes cannot match near tuning. Prioritize clean power with properly set gains over sheer wattage; an honest 1200-1500 watts will deliver everything most daily systems ask for.

Where is the terminal cup and how is the enclosure wired?

A single Proline X ABS and carbon fiber composite terminal cup is mounted on the side of the cabinet, which keeps the connection accessible when the vertical rear panel is tight against the cab wall. It is pre-wired internally with 12 gauge OFC to the driver position. Your final impedance is set by how you wire the Solo X's dual voice coils at the driver.

Will this wedge fit behind the seat of my truck?

It was drawn for exactly that spot. You need 26 inches of width, 18.25 inches of height, and 19.25 inches of floor depth; the top of the box needs only 12.625 inches because the baffle rakes back 20 degrees to follow the seat lean. The rear panel is fully vertical so it sits flat against the cab wall without wasting space. A 15 is a big driver, so measure your cab before ordering; in many mid-size and single-cab trucks this box belongs on the passenger side or centered with the seat forward one notch.

Is the subwoofer included with this enclosure?

No, this listing is the enclosure only. It is built specifically for the Kicker Solo X L7X 15 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 15 or an amplifier with it, call us at 931-563-5151.

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