Soundstream SPLX-124 (2006)
12″ subwoofer · 4 Ω · 1,000 W RMS
The Soundstream SPLX-124 (2006) is a 12″ subwoofer. With Qts 0.28 and EBP 101 it suits a ported box: deeper and louder; sealed, the bass sounds a bit dry.
| Source | web.archive.org · manufacturer data |
|---|---|
| Checked against source | October 2026 |
| Thiele/Small parameters | complete |
| Mounting dimensions | 0 of 4 — missing: cutout, mounting depth, frame outer diameter, magnet diameter; the designer will use an estimate |
- Re 0.26 Ω doesn't look like a 4 Ω coil — check the spec sheet.
- This sub has 4 voice coils — wiring options are calculated as for a single coil; check the final impedance against the spec sheet.
Recommended box
For a sedan, one sub, 1,000 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) | Dry and tight · 0.49 |
|---|---|
| Fc | 52 Hz |
| F3 (−3 dB, no cabin gain) | 85 Hz |
| Example box (outside) | 14 3/16″ × 14 3/16″ × 9 11/16″ |
Ported
deeper, louder| Tuning (Fb) | 33 Hz |
|---|---|
| Port | slot 3 1/8 × 14 5/16″, 45 1/16″ long |
| Port velocity at 1,000 W | 62 ft/s |
| F3 (−3 dB, no cabin gain) | 30 Hz |
| Example box (outside) | 31 1/2″ × 15 3/4″ × 16 1/8″ |
Deeper: 1.41 ft³ (40 L) tuned to 30 Hz, 31 1/2″ × 15 3/4″ × 10 5/8″ 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 | 1,000 W |
| Fs | 29.6 Hz |
| Qts | 0.28 |
| Qes | 0.294 |
| Qms | 5.89 |
| Vas | 1.42 ft³ |
| Re | 0.26 Ω |
|---|---|
| Sd | 74.4 in² |
| Xmax | 0.57″ |
| Vd | 42.2 in³ calc. |
| Mms | 235 g calc. |
| BL | 6.2 T·m calc. |
| EBP | 101 — suits ported calc. |
| Sensitivity, 1 W / 1 m | 87.5 dB calc. |
Mounting dimensions
| Cutout diameter | ≈ 11 1/8″ |
|---|---|
| Mounting depth | ≈ 5 7/8″ |
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 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 box
“≈” 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 Soundstream 12″ models
- Soundstream EXACT 12 12″ · 4 Ω
- Soundstream PCW-12 12″ · dual 4 Ω
- Soundstream PSW.124 12″ · 4 Ω
- Soundstream PWS-12 12″ · dual 4 Ω
- Soundstream PXW-12 12″ · dual 4 Ω
- Soundstream PXW-12/2 12″ · dual 2 Ω
- Soundstream R1-12 12″ · dual 4 Ω
- Soundstream R1-12L 12″ · dual 4 Ω
- Soundstream R3.12 12″ · dual 2 Ω
- Soundstream RBW-12 12″ · dual 4 Ω
- Soundstream RFW-12 12″ · dual 4 Ω
- Soundstream RW-12 12″ · dual 4 Ω
Similar 12″ subwoofers from other brands
Close in Fs, Qts and Vas — a box of similar volume will suit them.
- Elemental Designs E12o 0.71 ft³ sealed · 2.26 ft³ ported
- Pride LC V.2 12 D2 0.78 ft³ sealed · 2.47 ft³ ported
- Gladen SQX 12 Extreme (SVC 2 ohm) 0.71 ft³ sealed · 2.26 ft³ ported
- Audiobahn AW1208Q 0.64 ft³ sealed · 2.01 ft³ ported
- Audiobahn AW1208T 0.65 ft³ sealed · 2.01 ft³ ported
- Fi Audio SSD-EL 12 D1 0.67 ft³ sealed · 2.19 ft³ ported
FAQ
What box does the Soundstream SPLX-124 (2006) need?
Recommended net volume: 0.67 ft³ sealed, 2.19 ft³ ported tuned to 33 Hz — for one sub in a sedan at 1,000 W. Fit the box to your space and amp in the free calculator, with plans and a cut sheet.
What are the Soundstream SPLX-124 (2006) Thiele/Small specs?
Fs 29.6 Hz, Qts 0.28, Vas 1.42 ft³, Xmax 0.57″, Sd 74.4 in².
How much power does the Soundstream SPLX-124 (2006) handle and how do I wire it?
RMS power rating: 1,000 W. Wiring for several subs and amp power — in the wiring calculator.
Is the Soundstream SPLX-124 (2006) better sealed or ported?
EBP 101: a ported box (2.19 ft³, tuned to 33 Hz) suits it best — deeper and louder. Sealed (0.67 ft³) the bass is drier.
What port does the Soundstream SPLX-124 (2006) need?
For the 2.19 ft³ ported box tuned to 33 Hz: slot 3 1/8 × 14 5/16″, 45 1/16″ long, area 45.1 in²; or a round port Ø7 9/16″, ≈ 45 1/16″ long. Port air speed at 1,000 W: 62 ft/s.
What box do two Soundstream SPLX-124 (2006) subs need?
Two subs need twice the volume: 1.34 ft³ sealed, or 4.38 ft³ ported at the same 33 Hz tuning with twice the port area. One shared chamber or one per sub — whatever fits your vehicle.