3 Subwoofer Box Plans and Enclosure Options in 2026

#1. Goldwood TR12S: a ready-made sealed starting point

Goldwood TR12S sealed enclosure

Our verdict:

One sealed driver

A useful starting point when the driver calls for this size of sealed airspace.

Keep in mind: Resolve the volume convention before using the box label as a net target.

View on Amazon

• One unloaded 12-inch position
• 11-inch cutout; 11.75-inch mounting depth
• Published enclosure volume: 1.25 cubic feet

Choose the TR12S when a single sealed design fits your driver and you would rather buy the shell than cut it. Goldwood lists a 1.25 cubic foot volume, an 11-inch cutout and 11.75-inch mounting depth. The rear wall slopes, so depth near the magnet still needs a local check.

Compare this prefab with your own plan. It does not supply a cut list or say how much space your driver takes up. List the outside size, driver mounting face and usable airspace as three separate facts in the worksheet.

#2. Atrend 12SQV: compare a documented vented branch

Atrend 12SQV vented enclosure

Our verdict:

One vented driver

The maker gives a net volume and tuning, which helps compare an exact driver plan.

Keep in mind: Catalog and maker fit dimensions conflict; confirm the current drawing before purchase.

View on Amazon

• One unloaded 12-inch position
• Maker lists 1.2 cubic feet net and 36 Hz
• Maker lists 3/4-inch material

The 12SQV source states 1.2 cubic feet net and 36 Hz tuning. Use those to screen an exact driver's vented plan. Do not copy the tuning while changing the cavity, vent area or installed driver without checking the new alignment.

A complete vented cut list needs the vent parts too. The shell's six panels are not enough. A slot can share walls with the box, but each remaining partition still needs dimensions, a position and an occupied-volume entry. The stock 12SQV is an alternative to that custom work only if its fit and alignment actually agree with your requirements.

#3. Atrend 12DS: plan for two drivers

Atrend 12DS dual sealed enclosure

Our verdict:

Two sealed drivers

Use the maker's per-driver volume, rather than treating its headline figure as the whole box.

Keep in mind: Confirm the chamber arrangement and each mounting opening; do not treat the per-sub value as total volume.

View on Amazon

• Two unloaded 12-inch positions
• Maker lists 0.96 cubic feet net per sub
• Maker lists 11.4-inch mounting depth

Atrend's 12DS table gives 0.96 cubic feet net per sub, with 11.4-inch mounting depth. It is a dual sealed option, so it belongs on a two-driver plan. It cannot answer the space need of one unspecified woofer.

If you build a divided box, add the divider to the panel list. Count its solid volume too. Work out each side on its own. A total target helps you size the whole shell. It does not prove that each chamber has enough airspace.

Factors to consider when using subwoofer box plans

Use the free planning worksheets

Start the rectangular enclosure planner with the exact driver target and its volume convention. Choose an example to see how the ledger works, then replace those example inputs with your own source-backed values. Print or save the result only after the missing inputs and fit checks are resolved.

The wedge worksheet handles a sloping rear wall. Enter top and bottom depths on the same outside basis, plus actual wall thickness. It reports the cavity and slope, then sends the net-volume target back to the rectangular planner if useful. A sloped shell still needs a detailed joint drawing before cutting.

Both tools are free to use without an account. With JavaScript off, the labelled static example and formulas remain available. That example is a demonstration, not a plan for your own driver or vehicle. Browser print creates a worksheet; local JSON export preserves the entered record.

Read a cut list as a joint plan

Two boxes with the same outside width can need different side panels if one uses a full-width front and the other fits its front between the sides. Mark the joint arrangement before accepting any generated panel dimensions. Saw kerf and edge trimming also need room on the sheet.

KICKER's build guide explains the basic construction and cavity calculation. Use that as a method source. Then follow the driver-specific manual where it supplies a complete enclosure drawing. A general woodworking diagram does not choose the acoustic target.

Check a plan before copying it

Write the full driver model, source revision, target convention, wall thickness, occupied parts and mounting limits at the top of the record. If one item is missing, do not fill it from a different driver with the same diameter. The missing fact can change both the airspace and physical fit.

The cut sheet covers the shell. You still need to place the braces and driver holes. Add the fasteners, seals, wiring and a way to secure the box in the car. A volume sum cannot show where it is safe to drill. Resolve that part of the job before using the box.

More in this guide

• Exact-model size chart
• KICKER design conventions
• JL Audio worked designs
• Wedge volume worksheet
• What an oversized box changes
• What a box that is too small changes

How we picked the subwoofer box plans and stock options

The free tools follow the cited volume and geometry sources. The three stock choices cover one sealed driver, one vented driver and a sealed pair. We did not build these products or claim they fit an unnamed driver.

Subwoofer box plans verdict

Use these subwoofer box plans to turn your driver's target into a measured shell. Apply the same checks to the three stock boxes. We have not built or heard these boxes. For other stock-box choices, read the enclosure shortlist.