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Proline X PO 12-S DFW CompRT sealed down-fire wide enclosure for the Kicker CompRT, 41 inches wide by 7 inches tall, feet add 1.75 inches of height.
Proline X PO 12-S DFW CompRT sealed down-fire wide enclosure, end panel with side-mounted terminal cup, 7 inches tall by 14 inches deep.

Performance Optimized · Datasheet

Performance Optimized Down Fire Wide Sealed 12" Enclosure Kicker CompRT · Single 12" Sealed enclosure

Net volume
1.261 cu ft after the brace and displacement
Max mounting depth
3.75 in
External dimensions
41 in W × 7 in H × 14 in D
Front baffle
1.5 in double baffle, outer layer machined as a flush recess
Buy at Audio IntensityFactory-direct, ships from Tullahoma
Kicker CompRTBuy at Audio Intensity
  • Alignment: 1.261 cu ft net. 48CWRT124 D4 Qtc 1.134, Fc 47.5 Hz, F3 35.6 Hz; 48CWRT122 D2 Qtc 0.914, Fc 46.6 Hz, F3 38.3 Hz
  • Down Fire Wide: 41"W x 14"D x 7"H in down fire position, lower than the standard 30 x 15 (8.3125 in)
  • Height Set By: the airspace, matched to the standard 30 x 15 box
  • Driver: Kicker CompRT 12 (48CWRT124 D4 or 48CWRT122 D2), 13.35mm linear excursion, Fs 30.3 Hz and Vas 52.06 L on the D4, 3.75" mounting depth
  • Damping Note: D4 free-air Qts 0.7235, so system Qtc cannot fall below that in any sealed box

Spec of record

Technical specifications

SeriesProline X Performance Optimized Down Fire Wide
Compatible DriverKicker CompRT 12, 48CWRT124 (DVC 4 ohm) or 48CWRT122 (DVC 2 ohm). Direct fit
Enclosure TypeSealed, down fire, floor coupled
Intended FitmentWhere height or depth is the limit and 41 in of length is available
Firing DirectionDown firing. Feet ship uninstalled, so front or up firing is also possible
External Width41 in
External Depth14 in
External Height7 in, measured in down fire position, excludes feet
Installed Height8.75 in with the 1.75 in feet installed
Standard 30 x 15 Equivalent30 in W x 15 in D x 8.3125 in H, 1.25 cu ft net
Internal Height4.75 in
Internal Volume, Gross1.323 cu ft
Internal Volume, Net1.261 cu ft after the brace and displacement
Height Set ByAirspace; the motor clears the top panel with 2.5 in
Alignment, 48CWRT124 D4Qtc 1.134, Fc 47.5 Hz, F3 35.6 Hz, anechoic
Alignment, 48CWRT122 D2Qtc 0.914, Fc 46.6 Hz, F3 38.3 Hz, anechoic
Driver Fs30.3 Hz (D4, Klippel) / 28.6 Hz (D2, library)
Driver Qts0.7235 (D4) / 0.5605 (D2). Qtc cannot fall below Qts in any sealed box
Driver Qes / Qms0.7925 / 8.399 (D4, Klippel)
Driver Vas52.06 L (D4) / 59.19 L (D2)
Driver Bl19.1765 Tm (D4, Klippel)
Driver Mms192.33 g (D4, Klippel)
Driver Cms0.1435 mm/N (D4, Klippel)
Driver Re7.945 ohm (D4, Klippel)
Driver Sd506.71 cm² (Klippel)
Driver Xmax13.35mm linear (Klippel)
Driver Sensitivity84.66 dB (Klippel, 1W/1m)
Voice Coil ConfigurationDual voice coil. D4: 2 ohm parallel or 8 ohm series. D2: 1 ohm parallel or 4 ohm series
Mounting Depth3.75 in
Woofer Opening11 in
Driver Frame Diameter12.5625 in, sits on the 14 in baffle
Driver Displacement0.0538 cu ft, estimated (Kicker publishes none)
MaterialLangboard Elite 3/4 in MDF
JoineryV-groove and dado, CNC cut on ShopSabre routers
Panel Thickness0.75 in
Front Baffle1.5 in double baffle, outer layer machined as a flush recess
Internal BracingWindowed U-brace, dadoed to the shell
Corner ProfileSquare, Down Fire series standard
Driver Mounting8/32 threaded inserts, stainless machine screws included
Terminal CupOne Proline X ABS and carbon fiber composite, side mounted, pre-wired 12 gauge OFC
DampingPolyfill installed as a light wall lining, does not alter acoustic volume
Feet1.75 in, included, shipped uninstalled
CarpetPlush black
Bundle OptionsEnclosure only, bring your own 48CWRT124 or 48CWRT122
Warranty1 year limited
Built InTullahoma, Tennessee

Modelled response

Performance in this enclosure

Net airspace
1.261
cu ft per chamber
System Qtc
0.91–1.13
sealed
Half power
35.6–38.3
Hz · F3
Xmax at
345
W RMS · no filter
With 25 Hz subsonic
371
W RMS · +8%
Amplifier
250–500
W RMS recommended
This enclosure holds 1.261 cu ft net per chamber. In it the Kicker CompRT 12 (48CWRT122 / 48CWRT124) runs a system Qtc of 0.91–1.13 with half power at 35.6–38.3 Hz, and the cone reaches its 13.35 mm travel limit at 345 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 371 W — +26 W, or 8 percent more power for the same 13.35 mm of travel.

01Is it a sealed driver?

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

EBP = Fs ÷ Qes = 38.2–48.8
SEALED 0–50 TRANSITION 50–100 PORTED 100–150 0 50 100 150 D4 38.2 D2 (CWRT122, library set) 48.8
D4 · EBP 38.2D2 (CWRT122, library set) · EBP 48.8
EBP under 50 means a motor that wants a sealed load. The CompRT 12 (48CWRT122 / 48CWRT124) sits at 38.2–48.8, inside that band, which is why this is a sealed build rather than a ported one.

02What the box does to it

1.261 cu ft against a 52.1 L Vas.

α = Vas ÷ Vb = 1.46  ·  Fc = Fs√(α+1) = 47–48 Hz  ·  Qtc = 0.91–1.13
20 30 50 70 100 150 200 +6 +0 -6 -12 -18 -24 FREQUENCY · Hz LEVEL · dB −3 dB
D4 · Qtc 1.13, Fc 48 Hz, F3 35.6 HzD2 (CWRT122, library set) · Qtc 0.91, Fc 47 Hz, F3 38.3 Hz
The box lifts resonance from 28.6–30.3 Hz free-air to 47–48 Hz and half power lands at 35.6–38.3 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 13.35 mm — and a bigger one once a subsonic filter stops it wasting travel below the passband.

PXmax = 345–359 W unfiltered  →  371–379 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 13.35 mm 345 W reaches Xmax here
D4 · 359 W, no filterD2 (CWRT122, library set) · 345 W, no filterD4 · 371 W with subsonic at 25 Hz, 24 dB/octD2 (CWRT122, library set) · 379 W with subsonic at 25 Hz, 24 dB/octXmax 13.35 mm one-way
Every trace touches the limit and no further, because each is drawn at the exact power that puts that coil on 13.35 mm. Unfiltered that is 345 W, reached first at 29 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 371 W before hitting the same 13.35 mm. That is 8 percent more amplifier for the price of one filter setting.
ParamValueUnitNote
Fs30.30 / 28.60Hzfree-air resonance
Qts0.724 / 0.560D4 / D2 (CWRT122, library set)
Vas52.06 / 59.19Lequivalent compliance
Sd506.7cm²effective piston area
Xmax13.35mmone-way linear travel
Pe500Wcontinuous RMS
SPL84.5dB1 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.

From the shop floor

Installer's take

Same 1.261 cubic feet of air as our standard CompRT 12 box, give or take a hundredth, in a cabinet 7 inches tall instead of 8.3125. The motor clears the top by 2.5 inches, so we solved height to the volume and stopped there.

Fs 30.3 Hz and a 52 liter Vas on a shallow driver is unusual, and it is why the 48CWRT124 reaches a 35.6 Hz anechoic F3 here. The 12 uses the air you give it, which is why we did not shrink the volume to get the height down further.

The honest part: Qts is 0.7235 on the D4, so Qtc 1.134 is where it lands, with a modest lift near the corner. That is the CompRT's character. If you want it tighter, the 48CWRT122 at Qts 0.5605 sits at Qtc 0.914 in the same box.

Dual voice coil either way: D4 is 2 ohms parallel or 8 series, D2 is 1 ohm or 4. Most single-driver builds want the 2 ohm D4 setup.

Before you order

Questions

Why is this cabinet 41 inches wide instead of 30?

Because some installs run out of height or depth before they run out of length. The standard Kicker CompRT 12 Down Fire cabinet is 30 by 15 by 8.3125 inches; this one is 41 by 14 by 7. Spreading the airspace along 11 more inches lets the cabinet stand 1.3125 inches lower, and at 14 inches deep it is 1 inch shallower front to back, about the minimum a 12 inch frame needs.

If you have 41 inches of run and height or depth is the limit, this is the shape. If length is the limit, the standard 30 x 15 is the better fit.

How does this compare to the standard 30 x 15 Kicker CompRT 12 enclosure?

Same driver, same construction, different shape. The standard box is 30 by 15 by 8.3125 inches and holds 1.25 cubic feet net; this one is 41 by 14 by 7 inches and holds 1.261 cubic feet net.

The airspace is matched, so the alignment is effectively the same. The choice is about the shape of your space: the standard box when length is limited, this one when height or depth is the limit and you have 41 inches of run.

Why is the Qtc above 1.0 on the 48CWRT124? Is the enclosure undersized?

No. The 48CWRT124 has a free-air Qts of 0.7235, and system Qtc can never fall below the driver's Qts regardless of enclosure size. At 1.261 cubic feet net it lands at Qtc 1.134, which gives a modest lift near the corner and the punchy, forward presentation the CompRT is known for. Building larger would reduce Qtc only slightly, with diminishing returns and a taller cabinet. The 48CWRT122, with a lower Qts, lands at Qtc 0.914 in the same box.

Where do the Thiele-Small figures on this page come from?

For the 48CWRT124, Klippel measurement of the driver rather than a datasheet summary, which is why the page lists Cms, Bl, Mms, Sd, Qes and Qms alongside Fs, Qts and Vas. For the 48CWRT122 we use the library parameter set for that model. Both alignments were computed directly from those values at this cabinet's 1.261 cubic feet net.

How do I wire this enclosure and set my impedance?

The enclosure has one side-mounted Proline X terminal cup pre-wired in 12 gauge OFC. Both CompRT 12 versions are dual voice coil, so you set the load at the driver: the 48CWRT124 gives 2 ohms in parallel or 8 in series, and the 48CWRT122 gives 1 ohm in parallel or 4 in series. Most single-driver builds run 2 ohms. Confirm your amplifier is stable at that load before powering the system.

Why are the corners square instead of radiused?

Down Fire cabinets are built with square corners as a series standard. The 3 inch top down corner radius used on other Proline X alignments does not apply here. A down fire box is a low, wide platform that sits flat on a floor or cargo deck, and square corners maximize usable internal volume for a given footprint while keeping the cabinet stable.

How is this enclosure built?

V-groove and dado joinery, CNC cut on ShopSabre routers from Langboard Elite MDF. Every panel joint is a machined interlocking groove that mechanically locks the panels before adhesive is applied, which keeps the cabinet airtight under sustained pressure cycling. Corners are square, the Down Fire series standard.

The front baffle is a double layer at 1.5 inches, two bonded 3/4 inch sheets, with the outer layer machined as a flush recess so the driver bolts to the inner layer. A windowed U-brace ties the long 41 inch panels together and polyfill is installed as a light wall lining. Assembled and inspected in Tullahoma, Tennessee.

Is the Kicker CompRT subwoofer included with this enclosure?

No. This listing is for the enclosure only. Bring your own Kicker CompRT 12, 48CWRT124 or 48CWRT122. The cutout and mounting depth are direct fit.

Same series, same size

Other Performance Optimized models