Quantum Audio QW1000/12S4
12″ subwoofer · 4 Ω
The Quantum Audio QW1000/12S4 is a 12″ subwoofer. With Qts 0.84 and EBP 26 it suits a sealed box: tight bass in a small enclosure; a ported box would need a lot of volume. Modest excursion (Xmax 0.37″) — for clean sound at moderate levels, not for SPL competitions.
| Source | web.archive.org · manufacturer data |
|---|---|
| Checked against source | October 2026 |
| Thiele/Small parameters | not in the spec sheet: Re — typical value for the size used |
| 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) | Boomy, with a bump · 1.63 |
|---|---|
| Fc | 48 Hz |
| F3 (−3 dB, no cabin gain) | 35 Hz |
| Example box (outside) | 31 1/2″ × 15 3/4″ × 9 3/8″ |
Ported
deeper, louder| Tuning (Fb) | 30 Hz |
|---|---|
| Port | slot 1 9/16 × 14 5/16″, 23 9/16″ long |
| Port velocity at 300 W | 35 ft/s |
| F3 (−3 dB, no cabin gain) | 32 Hz |
| Example box (outside) | 31 1/2″ × 15 3/4″ × 13 5/16″ |
Deeper: 3.18 ft³ (90 L) tuned to 39 Hz, 31 1/2″ × 15 3/4″ × 15 3/16″ 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 | 4 Ω |
| RMS power | — |
| Fs | 24.9 Hz |
| Qts | 0.84 |
| Qes | 0.94 |
| Qms | 8.11 |
| Vas | 5.12 ft³ |
| Re | ≈ 3.4 Ω |
|---|---|
| Sd | 81.8 in² |
| Xmax | 0.37″ |
| Vd | 30.3 in³ calc. |
| Mms | 111 g calc. |
| BL | 7.9 T·m calc. |
| EBP | 26 — suits sealed calc. |
| Sensitivity, 1 W / 1 m | 85.8 dB calc. |
Mounting dimensions
| Cutout diameter | 10 13/16″ |
|---|---|
| Mounting depth | 5 3/16″ |
| Overall diameter | 12 3/8″ |
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 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 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 box
Cone area (Sd) calculated from Fs, Vas and Mms: 81.8 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
Voice coil versions
The same sub with different voice coils: the parameters are nearly the same — pick by your amp and wiring.
| Model | Voice coils | Re | Qes | Vas | Sealed | Ported |
|---|---|---|---|---|---|---|
| Quantum Audio QW1000/12S4 | 4 Ω | 3.4 Ω | 0.94 | 5.12 ft³ | 1.87 ft³ | 2.44 ft³ · 30 Hz |
| Quantum Audio QW1000/12D4 | dual 4 Ω | 3.4 Ω | 1.02 | 3.80 ft³ | 1.87 ft³ | 2.40 ft³ · 31 Hz |
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 QW3000/12D4 12″ · dual 4 Ω
- Quantum Audio QW5000/12D4 12″ · dual 4 Ω
- Quantum Audio QWX2000/12D4 12″ · dual 4 Ω
- Quantum Audio QWX4000/12D4 12″ · dual 4 Ω
Similar 12″ subwoofers from other brands
Close in Fs, Qts and Vas — a box of similar volume will suit them.
- Spyder Street 700 12 200W 1.73 ft³ sealed · 2.26 ft³ ported
- Spyder Street PWR 12 400W 1.73 ft³ sealed · 2.26 ft³ ported
- Pioneer TS-W126M 1.80 ft³ sealed · 2.37 ft³ ported
- Pioneer TS-W306R 1.80 ft³ sealed · 2.37 ft³ ported
- Pyle PLW12RD 1.73 ft³ sealed · 2.26 ft³ ported
- Soundstream SPL MULE 1.66 ft³ sealed · 2.15 ft³ ported
FAQ
What box does the Quantum Audio QW1000/12S4 need?
Recommended net volume: 1.87 ft³ sealed, 2.44 ft³ ported tuned to 30 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 QW1000/12S4 Thiele/Small specs?
Fs 24.9 Hz, Qts 0.84, Vas 5.12 ft³, Xmax 0.37″, Sd 81.8 in².
What is the Quantum Audio QW1000/12S4 mounting depth?
Mounting depth is 5 3/16″, cutout diameter 10 13/16″. The inside depth of the box must exceed the mounting depth by at least 1″.
Is the Quantum Audio QW1000/12S4 better sealed or ported?
EBP 26: a sealed box (1.87 ft³) suits it best — tight bass in a compact enclosure. Ported is possible (2.44 ft³, tuned to 30 Hz) but larger.
What port does the Quantum Audio QW1000/12S4 need?
For the 2.44 ft³ ported box tuned to 30 Hz: slot 1 9/16 × 14 5/16″, 23 9/16″ long, area 22.6 in²; or a round port Ø5 3/8″, ≈ 23 9/16″ long. Port air speed at 300 W: 35 ft/s.
What box do two Quantum Audio QW1000/12S4 subs need?
Two subs need twice the volume: 3.74 ft³ sealed, or 4.87 ft³ ported at the same 30 Hz tuning with twice the port area. One shared chamber or one per sub — whatever fits your vehicle.