Sealed and Ported, Wedge and Down Fire, 8 to 15 Inch

PowerBass Subwoofer Boxes and Enclosures

Sealed and ported enclosures cut for PowerBass subwoofers in wedge and down-fire, CNC-machined in Tullahoma, Tennessee.

Proline X subwoofer enclosures built for PowerBass subwoofers.

Sealed and Ported, Wedge and Down Fire, 8 to 15 Inch

PowerBass builds subwoofers across a wide range, and the enclosure that suits one of them does not suit another. These cabinets are cut per model: the sealed ones to the airspace PowerBass specifies, the ported ones to an alignment solved from its published parameters, in whichever shape the install allows.

Two decisions, in order. The vehicle picks the shape: down-fire if height is the constraint, wedge if floor space is. Then the driver picks how low it goes, and that range is wider than the diameters suggest.

Sealed and ported PowerBass enclosures from 8 to 15 inch, single and dual, in rear-firing wedge and down-fire, all Performance Optimized on a 1.5 inch double baffle.

Cut, assembled and finished in Tullahoma, Tennessee, to the airspace PowerBass publishes for each sealed build and to its published parameters for the ported ones.

Driver parameters, recommended airspaces and fitment dimensions are taken from PowerBass published data, including their owner's manuals and cutout templates. We build enclosures to those figures; we do not stock PowerBass drivers and make no claim to represent the brand.

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Two Shapes, and the Vehicle Picks

Every enclosure here is cut for a specific PowerBass driver, sealed or ported. The first decision is not the subwoofer, it is where the cabinet has to live.

Sealed Performance Optimized cabinets for PowerBass subwoofers, across two chassis. The ported wedges are covered below.
Down FireWedge
Goes whereUnder or behind a seatTrunk or cargo area
Constraint it solvesVertical heightFloor space
Installed height6.65 to 9.03 in including the 1.75 in standoff11 to 18 in, sits against the seat back
DriverXL-T shallow mount onlyXL, 2XL and 3XL conventional depth sealed; L, M, S, XL, 2XL and 3XL ported
Sizes10 and 12 inch, single or dual8, 10, 12 and 15 inch
Net airspace0.30 to 0.40 cu ft per driver0.50 to 2.25 cu ft per driver
AlignmentQtc 0.91 to 1.15, firm by necessity in that little airSealed Qtc 0.60 to 0.71, well damped; ported tuning per driver
Price from$239.99$229.99

Then the Driver Picks How Low It Goes

This is where the range differs most, and it is worth reading before you shop on diameter. Half power lands anywhere from 46 to 62 Hz depending on the driver, and the two sealed 12 inch wedges are 16 Hz apart from each other. A bigger cone does not mean a lower cabinet.

Sealed wedge alignments, ordered by how low each driver reaches. All figures anechoic, before cabin gain, computed from PowerBass published Thiele-Small parameters.
DriverOffered asQtcF3Character
XL-124412 inch, single or dual0.71446.2 HzThe deepest sealed reach in the range and a textbook Butterworth alignment.
3XL-1510D15 inch, single0.68046.1 HzSame reach as the XL-1244 with far more cone and a 1500 watt RMS rating.
2XL-1040D10 inch, single or dual0.63051.2 HzLong-throw 10 with 11.5 mm of travel, in the smallest cabinet of the 10s.
XL-104410 inch, single or dual0.63755.0 HzThe value 10. Efficient, easy to drive, modest excursion.
XL-8448 inch, dual only0.61059.8 HzFor builds with no room for a 10. Very stiff suspension, dry and quick.
2XL-1240D12 inch, single or dual0.60162.3 HzA Qts of 0.334 puts it past the knee for sealed loading. Big cone, big travel, but it gives up the low end a sealed 12 can otherwise reach.

Then the Ported Wedges

For more output than a sealed cabinet gives, ported wedges are cut for six PowerBass lines from 8 to 15 inch. Each carries a triangular corner slot port solved from that driver's published parameters, with the tuning frequency and net volume stated on the listing, and each ships without polyfill because fill would move the tuning.

Ported PowerBass wedges in stock, grouped by line. Single-driver cabinets.
LineModelsSizesNet volumeTuning
SS-84, S-1004, S-1004D, S-10T, S-10TD, S-1204, S-1204D, S-12T, S-12TD8, 10, 120.69 to 1.73 cu ft32.5 to 35.5 Hz
MM-1004, M-1004D, M-1204, M-1204D, M-1504, M-1504D10, 12, 151.15 to 2.22 cu ft28 to 33.5 Hz
LL-1004D, L-1204D, L-1504D10, 12, 151.13 to 2.02 cu ft31 to 34.5 Hz
XLXL-1004D, XL-1040, XL-1040D, XL-1040T, XL-1044, XL-104MF, XL-1204D, XL-1240, XL-1240D, XL-1240T, XL-1244, XL-124MF10, 120.82 to 2.23 cu ft32.5 to 37 Hz
2XL2XL-1204D, 2XL-1240D121.08 to 1.45 cu ft32.5 to 35 Hz
3XL3XL-1501D, 3XL-1502D152.33 to 2.36 cu ft32 to 32.5 Hz

Shared across every cabinet: Langboard Elite MDF cut on ShopSabre routers in Tullahoma, Tennessee. A 1.5 inch double front baffle. Plush black carpet. A Proline X ABS and carbon fibre composite terminal cup with stainless hardware, pre-wired in 12-gauge OFC. Threaded inserts at every mounting location. Polyfill installed in the sealed builds.

A Bigger Cone Is Not a Lower Box

Half power across the sealed cabinets runs from 46.1 Hz to 62.3 Hz, and the two sealed 12 inch wedges sit at opposite ends of that. The XL-1244 reaches 46.2. The 2XL-1240D reaches 62.3, because its Qts of 0.334 is past the knee for sealed loading. Both are correct for their driver. Read the alignment on the listing before you shop on diameter.

Cut to PowerBass Published Data

Airspace comes from the recommended enclosure tables in PowerBass owner's manuals. Cutout, mounting depth and frame diameter come from their cutout templates. Alignment is computed from their published Thiele-Small parameters, and on every 2XL and 3XL model our figures land within 0.02 on Qtc of what PowerBass prints themselves.

Wedge or Down Fire

The sealed wedges lean against the rear seat back and fire into the trunk. They take conventional depth drivers, hold 0.50 to 2.25 cubic feet per chamber and land between Qtc 0.60 and 0.71, which is a properly damped sealed alignment.

The down-fire cabinets exist for a different problem. A shallow mount driver is bought when a normal box will not fit, so these fire at the floor from a 1.75 inch standoff and occupy 6.65 to 9.03 inches of height. The airspace PowerBass specifies for those drivers is small, so the alignment is firmer by necessity.

The ported wedges are the third option. Cut for the L, M, S, XL, 2XL and 3XL lines in 8, 10, 12 and 15 inch, each carries a triangular corner slot port solved from that driver's published parameters, with the tuning frequency and net volume stated on the listing. They ship without polyfill, because fill would move the tuning.

Every cabinet is Performance Optimized. The sealed builds use the airspace PowerBass publishes for the driver, and each product page states its net volume, alignment and external dimensions.

Categories

PowerBass Subwoofer Box Questions

Which PowerBass subwoofers do these boxes fit?

Each cabinet is cut for one specific model, and the product title names it. The sealed wedges cover the XL-844, XL-1044, XL-1244, 2XL-1040D, 2XL-1240D and 3XL-1510D, and the sealed down-fire boxes the shallow mount XL-1040T and XL-1240T. The ported wedges cover the S, M, L, XL, 2XL and 3XL lines from 8 to 15 inch, with the model on every listing. Match the model, not the diameter: a shallow mount 10 and a conventional 10 share neither cutout nor mounting depth nor recommended volume.

Should I choose a wedge or a down-fire box?

The vehicle decides. A down-fire cabinet fires at the floor and stands 1.75 inches off it, so installed height runs 6.65 to 9.03 inches and it goes under or behind a seat. A wedge leans against the rear seat back and fires into the trunk, so it needs floor space rather than headroom. If a conventional box fits your trunk, the wedges use better drivers and reach lower.

Why do two 12 inch boxes have such different low-end?

Because the drivers are different. The XL-1244 reaches 46.2 Hz and the 2XL-1240D reaches 62.3 Hz, both anechoic, both in the airspace PowerBass specifies. The 2XL-1240D has a Qts of 0.334, which puts it past the knee for sealed loading, and no sealed cabinet takes it much below 61 Hz. It is the better driver on paper and the worse one in a sealed box. If low extension is the goal, the XL-1244 is the 12 to buy.

Why are the down-fire boxes a higher Qtc than the wedges?

Not by choice. A shallow mount driver exists for installs with no room, and PowerBass specifies 0.30 to 0.40 cubic feet for the XL-T models. That little air produces a firm alignment, Qtc 0.91 on the ten and 1.15 on the twelve. Firing down at a hard floor close to a boundary is what recovers some of the low end in the vehicle.

Do you sell PowerBass subwoofers?

No. We build the enclosure and you source the driver. The sealed cabinets are cut to the airspace PowerBass publishes for its own model and the ported ones to its published parameters, so they suit a subwoofer you already own or buy elsewhere.

What impedance will I see?

It depends on the driver. The XL-844, XL-1044 and XL-1244 are single 4 ohm voice coils, so a single is 4 ohms and a pair is 2 ohms in parallel. The 2XL models are dual 4 ohm. The 3XL-1510D is dual 1 ohm, which parallels to 0.5 ohms, so series 2 ohm wiring is the default answer on that one. Each product page states its own options.

Are these sealed or ported, and do they ship with polyfill?

Both. The sealed wedges and down-fire cabinets ship with polyfill already installed as a light lining; it damps the inside of the box and is part of how each cabinet was specified, so do not add or remove it. The ported wedges are solved from each driver's published parameters with a triangular corner slot port and the tuning stated on the listing, and they ship without polyfill because fill would move the tuning.

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Last updated September 5, 2026