Empty Bass Boxes

Why empty bass boxes work for serious installs in 2026

An empty bass box gives you the freedom to match a quality enclosure to a quality driver instead of accepting a pre loaded compromise. Choose the right internal volume and port size and the same subwoofer can sound clean and musical or huge and boomy. This category covers MDF enclosures from 8 to 15 inch in sealed, ported and bandpass formats.

Pre loaded bass packages are convenient but lock you into the supplied driver. Empty enclosures let you change subwoofers later without throwing away the box, which keeps long term ownership costs lower for serious SQ and SPL builders.

Sealed, ported and bandpass: enclosure design explained

Sealed boxes give tight, accurate bass that suits rock, jazz and SQ builds. Ported boxes vent through a tuned slot or tube for higher output at the tuning frequency, ideal for rap, EDM and SPL builds. Bandpass enclosures hide the driver behind a port and offer the loudest output in a narrow band.

Sizing your box to your driver

Every subwoofer has a manufacturer recommended internal volume in litres or cubic feet. Match the box net volume after subtracting the driver, port and bracing volume. Run the numbers in a simple WinISD model before ordering. A box that is 20 per cent too small kills output, while one that is too large risks unloading the cone at low frequencies.

Single and dual configurations

Single 12 inch sealed boxes fit most hatchback boots without losing the whole load space. Dual 12 inch ported boxes deliver the SPL builds want at the cost of a saloon boot. Twin 8 inch sealed enclosures suit Audi and BMW saloons that need real bass but cannot lose every inch of luggage space.

Box materials and build quality

Eighteen millimetre MDF is the standard for car audio enclosures and gives the right balance of weight, damping and price. Look for internally braced cabinets, recessed terminal cups and carpet finishes that resist scuffs. Avoid thin chipboard imports that flex audibly under power, killing output and adding distortion.

Brand quality at a glance

• KICKER. SoloX matched enclosures for SoloBaric L7 subs, vinyl wrapped finish.
• JL Audio. Premium MicroSub and CP series boxes with proper Q tuning.
• Vibe. Strong value MDF boxes in sealed and ported, UK market focused.
• Phoenix Gold. Heavy duty ported and bandpass boxes for SPL builds.
• Edge. Affordable ported and sealed boxes in 8 to 15 inch sizes.
• Audiocontrol. Specialty under seat and stealth enclosures for tight installs.

Compatibility and fitting

• Amp wiring kit. Required to run power, ground and remote turn on from the battery to your sub amp.
• Speaker cable. 16 AWG OFC minimum from amp to sub for a single 12 inch driver.
• ISO harness. Used at the head unit end if you are also fitting a new front stereo.
• Steering wheel control adapter. Maintains factory volume controls so the bass stays under your thumb.

Why buy empty bass boxes from Bass Junkies

Buying tips for 2026

Choose enclosure type by listening style before you pick the size. SQ minded listeners pick sealed. Rap and EDM fans pick ported tuned to 32 to 35 Hz. SPL builders pick large ported or bandpass tuned to the contest frequency. Always confirm the recommended box volume on the subwoofer datasheet before ordering. If a driver lists 28 to 32 litres sealed, do not order a 45 litre sealed box. We list internal litres on every Bass Junkies enclosure page.

Bass Junkies has built and sold bass boxes from our Wolverhampton workshop since 1995. We hold every common size in stock, can advise on sealed versus ported for your sub and ship boxes same day on weekday orders. Call 01902 863 005 with your subwoofer model and boot dimensions and we will recommend the right enclosure.