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Performance Optimized · Datasheet

Performance Optimized Wedge Enclosure | Fits Dual Kicker Solo X 8" Subwoofers Dual 8" Sealed enclosure

Net volume
0.51 Cubic Feet
Max mounting depth
7-15/16 Inches, Cleared With Margin
Cutout
7-5/16 Inches (Kicker Spec)
External dimensions
25.25 Inches W × 11.75 Inches H × 10 Inches / 14.25 Inches D
Front baffle
Double-Layer 1.5" MDF Plus Trim Layer
Buy at Audio Intensity
  • Alignment: Two identical sealed chambers, 0.51 cu ft net each (1.02 total). Dual 1-ohm 49L7X81s land at Qtc 0.707 (true Butterworth) per chamber, Fc 54 Hz, F3 54 Hz; dual 2-ohm 49L7X82s run Qtc 0.74, F3 52.2 Hz
  • Chambers: Full-height 3/4 in dado-locked divider, one driver per chamber, doubles as bracing across the 25.25 in span
  • Drivers: Pair of Kicker Solo X L7X 8s, matched coil versions. Each opening CNC-cut to 7-5/16 in per Kicker spec, 7-15/16 in depth cleared
  • Wiring: One shared side-mounted terminal cup, 12 gauge OFC to both positions. Kicker recommends 400-800 watts RMS per driver, 800-1600 system
  • Cabinet: 25.25 in W x 11.75 in H x 10/14.25 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 8 (49L7X81 / 49L7X82) | 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 Width25.25 Inches
External Height11.75 Inches
External Depth (Top)10 Inches
External Depth (Bottom)14.25 Inches
Total Internal Gross Volume1.22 Cubic Feet
Per-Chamber Net Volume0.51 Cubic Feet
Total Net Volume1.02 Cubic Feet
System Qtc Per Chamber (Dual 1-Ohm)0.707 Butterworth
System Qtc Per Chamber (Dual 2-Ohm)0.74
Predicted Fc Per Driver54 Hz (D1) / 54 Hz (D2)
Predicted F3 Per Driver (Anechoic)54 Hz (D1) / 52.2 Hz (D2)
Driver Fs (D1 / D2)48.0 Hz / 47.95 Hz (Kicker Factory)
Driver Qts (D1 / D2)0.630 / 0.651 (Kicker Factory)
Driver Vas (D1 / D2)3.75 L / 4.13 L (Kicker Factory)
Woofer Cutout (Each)7-5/16 Inches (Kicker Spec)
Mounting Depth Required (Each)7-15/16 Inches, Cleared With Margin
Recommended Power Per Driver400-800 Watts RMS (Kicker Recommendation)
Recommended System Power800-1600 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 8s)
Warranty1-Year Limited (Enclosure)
Built InTullahoma, Tennessee, USA

Performance in this enclosure

Net airspace
0.51
cu ft per chamber
System Qtc
0.71–0.74
sealed
Half power
52.2–53.8
Hz · F3
Xmax at
2371
W RMS · no filter
With 25 Hz subsonic
2804
W RMS · +18%
Amplifier
400–800
W RMS recommended
This enclosure holds 0.51 cu ft net per chamber. In it the Kicker SoloX L7X 8 (49L7X81) runs a system Qtc of 0.71–0.74 with half power at 52.2–53.8 Hz, and the cone reaches its 24.0 mm travel limit at 2371 W, above the driver’s 800 W thermal rating, so heat stops you before travel does. Run a subsonic filter at 25 Hz and that becomes 2804 W — +433 W, or 18 percent more power for the same 24.0 mm of travel.

01Is it a sealed driver?

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

EBP = Fs ÷ Qes = 62.3–65.3
SEALED 0–50 TRANSITION 50–100 PORTED 100–150 0 50 100 150 D1 65.3 D2 62.3
D1 · EBP 65.3D2 · EBP 62.3
At 62.3–65.3 the SoloX L7X 8 (49L7X81) 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

0.51 cu ft against a 3.8 L Vas.

α = Vas ÷ Vb = 0.26  ·  Fc = Fs√(α+1) = 54 Hz  ·  Qtc = 0.71–0.74
20 30 50 70 100 150 200 +6 +0 -6 -12 -18 -24 FREQUENCY · Hz LEVEL · dB −3 dB
D1 · Qtc 0.71, Fc 54 Hz, F3 53.8 HzD2 · Qtc 0.74, Fc 54 Hz, F3 52.2 Hz
The box lifts resonance from 48.0 Hz free-air to 54 Hz and half power lands at 52.2–53.8 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 24.0 mm — and a bigger one once a subsonic filter stops it wasting travel below the passband.

PXmax = 2371–2450 W unfiltered  →  2804–3018 W with a 25 Hz subsonic
20 30 50 70 100 150 200 0 8 16 24 FREQUENCY · Hz CONE TRAVEL · mm PAST LINEAR TRAVEL · Xmax 24.0 mm 2371 W reaches Xmax here
D1 · 2450 W, no filterD2 · 2371 W, no filterD1 · 3018 W with subsonic at 25 Hz, 24 dB/octD2 · 2804 W with subsonic at 25 Hz, 24 dB/octXmax 24.0 mm one-way
Every trace touches the limit and no further, because each is drawn at the exact power that puts that coil on 24.0 mm. Unfiltered that is 2371 W, reached first at 20 Hz. It sits above the 800 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 2804 W before hitting the same 24.0 mm. That is 18 percent more amplifier for the price of one filter setting.
ParamValueUnitNote
Fs48.00 / 47.95Hzfree-air resonance
Qts0.631 / 0.651D1 / D2
Vas3.75 / 4.13Lequivalent compliance
Sd249.6cm²effective piston area
Xmax24mmone-way linear travel
Pe800Wcontinuous RMS
SPL79.4dB1 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

Two 8s in matched Butterworth chambers is one of the smartest space-to-output plays in car audio. You get roughly 10-inch-class cone area split across two fast, high-excursion drivers, each in its own 0.51 cubic foot chamber at Qtc 0.707, and the pair stays only 11.75 inches tall. About 6 dB more capability than the single 8 with the identical sonic character.

The divider is not decoration. Two drivers sharing one volume modulate each other: every compression stroke from one becomes the other's pressure environment, which smears the alignment both would have alone. A full-height dado-locked wall gives each 8 its own sealed air and doubles as the brace that keeps the 25-inch panels quiet.

Buy both drivers in the same coil version and wire them identically off the shared cup. Mismatched coils or asymmetric wiring splits power unevenly between chambers and undoes the matching the box was built for. Plan 800-1600 clean watts across the pair, 400-800 per driver per Kicker's recommendation.

Fit check: 25.25 wide, 11.75 tall, 14.25 deep at the floor tapering to 10 up top. The low height is the killer feature; this slides behind seats that a taller dual 10 or single 12 wedge cannot, and cabin gain fills in below the mid-50s knee exactly where the alignment leans on it.

Questions

Will my Kicker Solo X 8s fit this enclosure?

Yes. Each baffle opening is CNC-cut to Kicker's published 7-5/16 inch cutout for the Solo X L7X 8, and each chamber clears the required 7-15/16 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 sealed alignment only means something when each driver owns its air. In a shared volume, each cone's compression stroke changes the pressure the other cone sees, which smears transients and blurs the Qtc both drivers were supposed to have. The full-height 3/4 inch divider gives each Solo X 8 its own 0.51 cubic feet at Qtc 0.707, keeps the pair perfectly matched, and stiffens 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. The chambers are identical, so matched drivers wired identically share power evenly and move in lockstep. Mixing coil versions creates unequal impedances off the shared terminal cup, which splits amplifier power unevenly and unbalances the pair. Pick the coil version whose wiring options land at the final impedance your amplifier wants.

How much power should I run to a pair of Solo X 8s?

Kicker recommends 400-800 watts RMS per Solo X 8, so plan 800-1600 watts RMS of clean power across the pair at your wired impedance. The sealed chambers keep excursion controlled as level climbs, so the top of that range is genuinely usable with properly set gains. A single quality monoblock feeding the shared cup is the standard setup.

How does a pair of 8s compare to a single 12?

Cone-area math puts two 8s a little under one 12, but the comparison is really about shape and speed. The pair spreads its displacement across two lighter, faster cones and fits a cabinet only 11.75 inches tall, where our single 12 wedge stands 15.25. The 12 digs deeper anechoically with its lower F3; the dual 8s counter with transient snap and a fit-anywhere profile. If your seat clearance is tight, the 8s win before the music even starts.

Will this wedge fit behind the seat of my truck?

You need 25.25 inches of width, 11.75 inches of height, and 14.25 inches of depth at the floor; the top needs only 10 inches thanks to the 20 degree baffle rake. The vertical rear panel sits flat against the cab wall. The low 11.75 inch height is what makes this box work behind seats where taller enclosures will not let the seat latch back.

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 8s, 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 8s or matching an amplifier, call us at 931-563-5151.

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