Sealed, 8 Inch

Sealed 8 Inch Subwoofer Boxes

Sealed cabinets for 8 inch drivers, standard and wedge, with the net volume on every card. CNC-cut in Tullahoma.

Sealed 8 inch Proline X subwoofer enclosure

Sealed, 8 Inch

A sealed 8 inch subwoofer box is the alignment that trades a little output for control: the trapped air behind the cone acts as a spring, roll-off is gentle, and the cabin's own gain below 45 Hz fills in what the box gives up. Every cabinet on this page is cut for a 8 inch driver, and the listing states the net volume, which is the only number a sealed box is really about.

An eight is the size you choose when the space is the constraint, and the only size where we build a quad cabinet. CNC-cut in Tullahoma, Tennessee from Langboard Elite MDF on our own ShopSabre routers, polyfill installed. We run the machines.

Sealed 8 inch cabinets in stock today | single, dual, triple and quad | standard and wedge | Performance and Performance Optimized | polyfill installed

Cut, assembled, carpeted and shipped from our own shop in Tullahoma, Tennessee. Stock counts on every card are shelf counts. Every sealed cabinet ships with polyfill installed. Limited warranty runs by series from the original date of purchase: one year on Performance and Performance Optimized.

Specified and written by Scott Welch, IASCA National and MECA World Champion, who runs the CNCs these are cut on. Figures come from our own build sheets and the driver manufacturers' published parameters.

Decision Shortcut

Find Your Match

Curated picks matched to common build goals

Best for Trucks

Performance Optimized Series PO 8D-S W XL speaker enclosure by Proline, featuring a black frame with two circular openings, shown on a dark blue background with dimensions labeled 32 inches wide and 11 inches deep.

Proline X

PowerBass XL-844 Dual Box: Sealed 8" Wedge Enclosure

PowerBass XL-844. A wedge cabinet tapered to sit flush against a seat back.

$ 249.99

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Shallowest Cabinet

Proline X PO 8-S W Solo X sealed wedge, front baffle with gloss black insert and pre-wired leads, 13.5 by 11.8 inches.

Proline X

Kicker Solo-X 8 Box: Sealed 8" Wedge Enclosure

Performance Optimized Wedge cabinet that fits Kicker Solo X 8" Subwoofer. 10 inches deep, among the shallowest sealed 8 inch cabinets in stock, for openings a standard box will not take.

$ 319.99

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Most Airspace

Two car audio (1 black & 1 grey) subwoofer enclosures with visible brand logo on a white background

Proline X

Proline X P8-S | Single 8" Sealed Subwoofer Enclosure | V3

P8-S Single 8" Sealed Subwoofer Enclosure. 0.5 cubic feet net, among the most air behind an 8 inch cone in a single-driver cabinet on this page, for drivers that want a large sealed volume.

$ 129.99

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Sealed or Ported at 8 Inches

Same driver size, same shop, same materials. The alignment changes the cabinet, what the listing has to tell you and what you do at the amplifier. This page is the sealed half; the ported 8 inch page is the other.

Sealed and ported 8 inch Proline X cabinets as built, 5 September 2026.
Sealed 8 inchPorted 8 inch
Net volumeSmaller for the same driverLarger, with the port's own volume added
PolyfillInstalled on every buildNone. Ships dry so the tuning holds
Tuning statedNo, a sealed box has noneYes, on every listing
OutputFlat passband, gentle 12 dB per octave roll-offMore output around tuning for the same power
Subsonic filterAn improvementA requirement, set just under tuning
Pick it whenSpace is tight, music is wide, or you want a dualThe space is there and output per watt matters

Shared across both: Langboard Elite MDF at 48.5 lbs per cubic foot, 200 psi internal bond and 410,000 psi MOE, cut on ShopSabre routers in Tullahoma and carpeted in house.

Two Shapes, Two Series

The page spans standard and wedge cabinets from the Performance and Performance Optimized lines, in single, dual, triple and quad configurations. Brands we cut sealed 8 inch cabinets for include Kicker; the card says whether we stock the driver as well, because the box is the product and it has to be right on its own.

Limited warranty runs by series from the original date of purchase: one year on Performance and Performance Optimized.

The straight cabinet

Standard 8 inch, sealed

single, dual, triple and quad, sealed·From $94.00

Fires forward, stands on its base. The shape for a trunk with height or a cargo floor with room behind the seat.

1 year limited warranty on Performance

Leans on the seat back

Wedge 8 inch, sealed

single, dual and triple, sealed·From $229.99

Tapered on the rear panel to sit flush against a seat. The truck cabinet, and the shape that leads at the larger sizes.

1 year limited warranty on Performance Optimized

Prices are the lowest in stock for each shape today. Depth, net volume and, on ported builds, tuning are what change from card to card.

Categories

Keep Reading

Supporting guides to help you design, build, and tune your system.

Sealed 8 Inch Box Questions

How big is a sealed 8 inch subwoofer box?

Net volume on this page runs 0.4 to 0.5 cubic feet for a single-driver cabinet, and every listing states its own. The driver-matched builds are cut to one driver's published parameters; the universal-cutout cabinets sit in the range a typical 8 inch driver wants. Net volume is what is left after the driver and the bracing, so read that rather than the outside dimensions.

Does a sealed 8 inch box need polyfill?

It is already in. Every sealed cabinet we build ships with polyfill installed, weighed to the volume of the box. It makes the cabinet behave as if it were slightly larger and damps internal reflections. Leave it as shipped.

Sealed or ported for a 8 inch sub?

Sealed is the smaller cabinet, forgives a wrong-sized car and is the safer choice for wide-ranging music. Ported gives more output around its tuning for the same power from a larger box and needs a subsonic filter. If depth or height is the limit, sealed. If the space is there and output matters, the ported 8 inch page is the other half of this decision.

Can I put a different 8 inch driver in one of these?

In a universal-cutout cabinet, yes, as long as the driver's mounting depth clears the cabinet depth on the listing and its recommended sealed volume is close to the net volume stated. In a driver-matched build the volume was solved for one driver, so a different one will work but will not be optimised.

Do you make dual sealed 8 inch boxes?

Yes. This page carries dual, triple and quad cabinets alongside the singles. The listing states the net volume; on a dual check whether the figure is per chamber or for the whole cabinet.

What is the warranty on a sealed 8 inch box?

Limited warranty runs by series from the original date of purchase: one year on Performance and Performance Optimized. It covers structural failure and manufacturing defects for the original purchaser.

Subwoofer Boxes by Brand

Every box is cut to one driver's published specs. Pick the brand your subwoofer comes from.

Drivers Built to Match

8 Inch Subwoofers Spec'd for These Sealed Boxes

The drivers below are matched to the enclosures above by Thiele-Small parameters. Buying together guarantees the alignment, port tuning, and damping work the way the engineering intended.

Image Dynamics ID8 V4 8inch Subwoofer

Image Dynamics

Image Dynamics ID8 V4 8inch Subwoofer

$ 99.99
Prodigy Audio 8 inch Subwoofer NB2 Series - Prodigy Subwoofer for car audio systems

Prodigy Audio

Prodigy Audio 8 inch Subwoofer | NB2 Series

$ 108.99 $ 115.99
Image Dynamics IDQ8 V4 8inch Subwoofer

Image Dynamics

Image Dynamics IDQ8 V4 8 inch Subwoofer

$ 193.99
Arc Audio Arc Series 8 inch Subwoofer

Arc Audio

Arc Audio Arc Series 8 inch Subwoofer

$ 239.00

View all 8 inch subwoofers | Need a custom build? Contact us

Amplifiers for the System

Power for Your Subwoofer System

Monoblock amplifiers matched to the power requirements of the drivers these enclosures are built for. Buy the enclosure, match the driver, pick the right amplifier.

Prodigy Audio 1200 Watt Mono Block Amplifier NBM1200.1 - Prodigy Amplifier for car audio systems

Prodigy Audio

Prodigy Audio 1200 Watt Mono Block Amplifier | NBM1200.1

$ 272.99 $ 326.99
Wavtech Link5001Mini

Wavtech

Wavtech Link5001Mini

$ 299.99
US Acoustics Mike 1500w Monoblock Amplifier US Acoustics

US Acoustics

US Acoustics Mike 1500w Monoblock Amplifier

$ 329.99
Image Dynamics SQ600.1D 600W Mono Block Amplifier

Image Dynamics

Image Dynamics SQ600.1D 600W Mono Block Amplifier

$ 399.99

View all monoblock amplifier | Need a custom build? Contact us

Amplifiers for the System

Power for Your Subwoofer System

Monoblock amplifiers matched to the power requirements of the drivers these enclosures are built for. Buy the enclosure, match the driver, pick the right amplifier.

Rainbow Audio Dream 0.5K Mono Class D Amplifier

Rainbow

Rainbow Audio Dream 0.5K Mono Class D Amplifier

$ 89.99 $ 399.99
US Acoustics Lisa 4 Channel Class AB Amplifier 4 x 50w US Acoustics

US Acoustics

US Acoustics Lisa | 4 Channel Class AB Amplifier | 4 x 50w

$ 159.99
US Acoustics Wendy 2 Channel Class AB Amplifier 2 x 75w US Acoustics

US Acoustics

US Acoustics Wendy | 2 Channel Class AB Amplifier | 2 x 75w

$ 159.99
Prodigy Audio 600 Watt 4 Channel Amplifier NBM100.4 - Prodigy Amplifier for car audio systems

Prodigy Audio

Prodigy Audio 600 Watt 4 Channel Amplifier | NBM100.4

$ 225.99 $ 270.99

View all car amplifiers | Need a custom build? Contact us

Last updated September 5, 2026