A complete, ready-to-build sealed subwoofer enclosure plan designed specifically for the Dayton Audio UMII15-22 Ultimax II 15" DVC Subwoofer 2 Ohms Per Coil (dual driver). The finished box measures 832 × 449 × 630 mm (W × H × D). Every dimension is whole-millimetre and verified in 3D, and because it ships with full-size 1:1 print-at-home templates, you can build it dead-accurate even without a CNC. Every fitted detail is already built into the plans (2 recessed steel side handles, a recessed 2-pole Speakon connector panel, a protective front grille on an excursion-clearing lip and a self-locating stacking system), so it goes together as one finished, gig-ready build. Download, print, tape, trace, cut, glue and drop your driver in. What you get Per-panel DXF cut files + a nested cut sheet for an efficient single-board cut Full-size 1:1 print-and-tape A4 templates (PDF) so you can build it accurately with no CNC STEP + STL 3D models so you can preview the exact box before you cut Printable cut list (CSV) with every panel + the driver cutout Separate grille cut file (DXF) + its own 1:1 A4 template, so you can cut the grille from a sheet of perforated mesh metal Recessed-hardware cut-outs built into the panels (2 side-handle recesses and the Speakon connector recess), centred and gasket-sealed, with the mounting bolts marked Predicted-performance charts (response, max SPL, excursion, impedance) Full internal & external dimensions Stacking system: marked foot positions + top alignment pockets with sealed backing plates, so identical boxes stack and self-locate (feet not included) Build it without a CNC No CNC, no laser cutter, no problem. Every panel and brace also comes as a full-size 1:1 PDF, tiled across ordinary A4 paper. Print at 100%, butt the full sheets together edge-to-edge and tape them on the back (no trimming, no guesswork), then lay the template on your board, trace the lines and cut with a jigsaw or router. Every sheet has a printed 100 mm ruler so you can confirm the scale is spot-on before you cut, and each part comes with a one-page map showing exactly how its sheets line up. Got a CNC? Feed it the DXF files instead, and either way you build the very same box. Bracing that anyone can build (drill or CNC) Inside, an interlocking egg-crate of window braces locks together with half-lap joints and glues to all six panels, stiffening the box and pushing its panel resonances well above the bass it plays. To stay rigid but acoustically open, every brace is lightened with a grid of round holes sized to standard hole-saw diameters (around 32 to 76 mm). That means you can bore them with cheap, off-the-shelf bits from any hardware store, in a fraction of the time it takes to jigsaw square windows out, and round holes are stronger because there are no sharp corners to crack. Prefer a CNC? The exact same holes are already in the DXF cut files, so the machine cuts them along with the panel outline in one pass. Either way the 1:1 paper templates mark every hole centre for you, and the driver, handle and amplifier/connector clearances are carved into the braces and verified in 3D so nothing ever fouls. Design specs Driver: Dayton Audio UMII15-22 Ultimax II 15" DVC Subwoofer 2 Ohms Per Coil ×2 (shared chamber) Alignment: Sealed, Qtc 1.02 Net volume: 170 L total (85 L/driver) Tuning: Fc 43 Hz · F3 33 Hz External (W×H×D): 832 × 449 × 630 mm Material: 18 mm MDF/plywood Max SPL: 123 dB @ 59 Hz (900 W/driver) Sensitivity: 92 dB (system, 2 drivers) Impedance: 2.0Ω parallel / 8.0Ω series Array coupling: +6 dB up to 192 Hz when arrayed (449 mm centres) Handles: 2x Penn Elcom H1105 recessed steel side handles (1 per side) Connectors: Penn Elcom D0604 recessed back panel (2x Speakon) Grille: 2 mm inset grille on a 31 mm front lip, 8 support blocks (perforated steel or mesh, customer supplied) Stacking: 4x Adam Hall 4907TP rubber feet; 40 mm top pockets self-locate stacked boxes (panels carry the load, pockets sealed by glued backing plates) Alignment: Manufacturer (85 L) Group delay: 7.6 ms @ Fc Driver T/S: Fs 29.34 Hz · Qts 0.7014 · Vas 96 L · Xmax 24 mm · Pe 900 W Hardware you'll need The plan is cut to fit these exact parts, so order these and they drop straight in (every recess is built around their real measured dimensions): Penn Elcom H1105: 2 recessed steel side handles (sealing gasket included with the handle); the 1-per-side recesses are cut to this exact handle Penn Elcom D0604: recessed back-panel dish for 2x Speakon connectors; the cut-out is sized to this exact dish Adam Hall 4907TP: 4x rubber stacking feet (38 mm dia); the foot marks and 40 mm top pockets are sized for these Perforated mesh metal sheet: any perforated steel or aluminium sheet; cut the grille to size from the included grille DXF / 1:1 A4 template Dayton Audio UMII15-22 Ultimax II 15" DVC Subwoofer 2 Ohms Per Coil: the subwoofer driver itself (not included) Why this box Aligned to the manufacturer / target Qtc, not a generic box Egg-crate window braces lightened with round drilled holes: stiff, acoustically open, and quick to make with a hole saw or a CNC Driver, handle and connector/amp clearances carved into the braces and checked in 3D so nothing fouls Whole-millimetre cuts for accurate DIY woodworking Every fitted detail (2 recessed steel side handles, a recessed 2-pole Speakon connector panel, a protective front grille on an excursion-clearing lip and a self-locating stacking system) is engineered into the panels and gasket-sealed, not bolted on as an afterthought How to build Two ways to cut: print the full-size A4 templates, tape them up and trace onto your board (drilling the round brace holes with a hole saw), or send the DXF files to a CNC that cuts every outline and hole in one pass. Then assemble the butt-jointed box, slide the interlocking braces together and glue them in, seal the joints, fit the recessed hardware and mount your driver in the pre-sized cutout. Searching for a Dayton Audio UMII15-22 Ultimax II 15" DVC Subwoofer 2 Ohms Per Coil 15" subwoofer box plan or sealed enclosure design you can actually build at home? This plan gives you the exact 170 L sealed box tuned to Fc 43 Hz / F3 33 Hz, with print-at-home templates, DXF cut files and 3D models included. Instant digital download. 30-day money-back guarantee.