Quantum Audio QW5000/12D4
12″ subwoofer · dual 4 Ω
The Quantum Audio QW5000/12D4 is a 12″ subwoofer. With Qts 0.54 and EBP 54 it works both sealed and ported: sealed is tighter and smaller, ported is deeper and louder.
| Source | web.archive.org · manufacturer data |
|---|---|
| Checked against source | October 2026 |
| Thiele/Small parameters | complete |
| Mounting dimensions | 3 of 4 — missing: magnet diameter; the designer will use an estimate |
Recommended box
For a sedan, one sub, 300 W. It’s the same math as the designer’s step-by-step mode, where you can fit the box to your space, vehicle and amp and get plans, a cut sheet and DXF.
Sealed
smaller, tighter| Bass character (Qtc) | Tight and punchy · 0.79 |
|---|---|
| Fc | 60 Hz |
| F3 (−3 dB, no cabin gain) | 57 Hz |
| Example box (outside) | 14 3/16″ × 14 3/16″ × 10 7/16″ |
Ported
deeper, louder| Tuning (Fb) | 34 Hz |
|---|---|
| Port | slot 1 9/16 × 14 5/16″, 36″ long |
| Port velocity at 300 W | 41 ft/s |
| F3 (−3 dB, no cabin gain) | 33 Hz |
| Example box (outside) | 21 7/16″ × 15 3/4″ × 13 3/4″ |
Deeper: 2.15 ft³ (61 L) tuned to 33 Hz, 31 1/2″ × 15 3/4″ × 12″ outside — a bigger box with flatter deep bass. Open in the calculator
Projects with this subwoofer
Boxes that users designed and published: plans, cut sheet and response graph.
Thiele/Small parameters
| Size | 12″ |
|---|---|
| Voice coils | dual 4 Ω |
| RMS power | — |
| Fs | 40.8 Hz |
| Qts | 0.54 |
| Qes | 0.752 |
| Qms | 1.93 |
| Vas | 0.84 ft³ |
| Re (one coil) | 3.4 Ω |
|---|---|
| Sd | 82.4 in² |
| Xmax | 0.60″ |
| Vd | 49.3 in³ calc. |
| Mms | 255 g calc. |
| BL | 17.2 T·m calc. |
| EBP | 54 — sealed or ported calc. |
| Sensitivity, 1 W / 1 m | 85.3 dB calc. |
Mounting dimensions
| Cutout diameter | 10 13/16″ |
|---|---|
| Mounting depth | 6 1/2″ |
| Overall diameter | 12 7/16″ |
Where it fits in a vehicle
Spots from our vehicle guides where the cutout, mounting depth and recommended box fit. The spot sizes are approximate — measure your own vehicle.
- Bronco 4-door — behind the rear seat sealed and ported box
- Wrangler 4-door, hard top — behind the rear seat sealed and ported box
- Wrangler 4-door, soft top — behind the rear seat sealed and ported box
- Silverado / Sierra Crew Cab — under the rear seat sealed and ported box
- Spare tire well sealed box
- FJ Cruiser — behind the rear seat sealed and ported box
- El Camino 1978–87 — behind the seat sealed and ported box
- Cherokee XJ — cargo area, spare moved out sealed and ported box
- Excursion — behind the third row sealed and ported box
- Mustang 2015–2023 coupe — trunk sealed and ported box
- Challenger / Charger — trunk sealed and ported box
- Club Car Precedent — under the rear seat sealed and ported box
Cone area (Sd) calculated from Fs, Vas and Mms: 82.4 in².
“≈” means the value isn’t in the spec sheet and a typical value for the size is used; “calc.” means it’s calculated from the published parameters. Check the manufacturer’s spec sheet before you build.
Data sources
Other Quantum Audio 12″ models
- Quantum Audio Q800/12D 12″ · dual 4 Ω
- Quantum Audio Q800/12S 12″ · 4 Ω
- Quantum Audio Q2000/12D 12″ · dual 4 Ω
- Quantum Audio Q2500/12D 12″ · dual 4 Ω
- Quantum Audio Q3000/12D 12″ · dual 4 Ω
- Quantum Audio QFW12D4 12″ · dual 4 Ω
- Quantum Audio QPW3000/12D4 12″ · dual 4 Ω
- Quantum Audio QSW12F 12″ · 4 Ω
- Quantum Audio QW1000/12D4 12″ · dual 4 Ω
- Quantum Audio QW1000/12S4 12″ · 4 Ω
- Quantum Audio QW3000/12D4 12″ · dual 4 Ω
- Quantum Audio QWX2000/12D4 12″ · dual 4 Ω
Similar 12″ subwoofers from other brands
Close in Fs, Qts and Vas — a box of similar volume will suit them.
- Audiopipe TXX-APC-12 0.74 ft³ sealed · 1.31 ft³ ported
- Ground Zero GZHW 12SPL (2x2 Ohm) 0.71 ft³ sealed · 1.20 ft³ ported
- Triton Trooper 12 1.02 ft³ sealed · 1.09 ft³ ported
- Soundstream SPLX-122 ('07-'08) 0.67 ft³ sealed · 1.20 ft³ ported
- DB Drive WDX12G5.2 0.76 ft³ sealed · 1.31 ft³ ported
- American Bass XD-1222 1.17 ft³ sealed · 1.27 ft³ ported
- Ground Zero GZNW 30SPL-D2 (2x2 Ohm) 0.88 ft³ sealed · 2.12 ft³ ported
FAQ
What box does the Quantum Audio QW5000/12D4 need?
Recommended net volume: 0.74 ft³ sealed, 1.31 ft³ ported tuned to 34 Hz — for one sub in a sedan at 300 W. Fit the box to your space and amp in the free calculator, with plans and a cut sheet.
What are the Quantum Audio QW5000/12D4 Thiele/Small specs?
Fs 40.8 Hz, Qts 0.54, Vas 0.84 ft³, Xmax 0.60″, Sd 82.4 in².
What is the Quantum Audio QW5000/12D4 mounting depth?
Mounting depth is 6 1/2″, cutout diameter 10 13/16″. The inside depth of the box must exceed the mounting depth by at least 1″.
Is the Quantum Audio QW5000/12D4 better sealed or ported?
EBP 54: both work — sealed 0.74 ft³ is tighter and smaller, ported 1.31 ft³ tuned to 34 Hz is deeper and louder.
What port does the Quantum Audio QW5000/12D4 need?
For the 1.31 ft³ ported box tuned to 34 Hz: slot 1 9/16 × 14 5/16″, 36″ long, area 22.6 in²; or a round port Ø5 3/8″, ≈ 36″ long. Port air speed at 300 W: 41 ft/s.
What box do two Quantum Audio QW5000/12D4 subs need?
Two subs need twice the volume: 1.48 ft³ sealed, or 2.61 ft³ ported at the same 34 Hz tuning with twice the port area. One shared chamber or one per sub — whatever fits your vehicle.