Soundstream SPLX-122HX
12″ subwoofer · dual 2 Ω · 1,000 W RMS
| 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, 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) | Flat and accurate · 0.68 |
|---|---|
| Fc | 54 Hz |
| F3 (−3 dB, no cabin gain) | 58 Hz |
| Example box (outside) | 14 3/16″ × 14 3/16″ × 10 1/16″ |
Ported
deeper, louder| Tuning (Fb) | 34 Hz |
|---|---|
| Port | slot 1 9/16 × 14 5/16″, 37 1/8″ long |
| Port velocity at 1,000 W | 81 ft/s |
| F3 (−3 dB, no cabin gain) | 33 Hz |
| Example box (outside) | 20 11/16″ × 15 3/4″ × 14 3/16″ |
Deeper: 1.52 ft³ (43 L) tuned to 33 Hz, 31 1/2″ × 15 3/4″ × 12 1/16″ 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 | dual 2 Ω |
| RMS power | 1,000 W |
| Fs | 31.8 Hz |
| Qts | 0.41 |
| Qes | 0.45 |
| Qms | 4.14 |
| Vas | 1.30 ft³ |
| Re (one coil) | 1.9 Ω |
|---|---|
| Sd | 79.2 in² |
| Xmax | 0.73″ |
| Vd | 58 in³ calc. |
| Mms | 251 g calc. |
| BL | 14.6 T·m calc. |
| EBP | 71 — sealed or ported calc. |
| Sensitivity, 1 W / 1 m | 86.2 dB calc. |
Mounting dimensions
| Cutout diameter | 11″ |
|---|---|
| Mounting depth | 7″ |
| Overall diameter | 12 5/8″ |
“≈” 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.
- PowerBass 3XL-121D 0.71 ft³ sealed · 1.27 ft³ ported
- SSA ICON 12 D4 0.67 ft³ sealed · 1.20 ft³ ported
- American Bass ELITE-1222 0.71 ft³ sealed · 1.27 ft³ ported
- Resilient Sounds RS 12 V2 D4 0.74 ft³ sealed · 1.31 ft³ ported
- Kicker CompVX 12" 2-Ohm DVC (50CVX122) 0.74 ft³ sealed · 2.40 ft³ ported
- PowerBass 3XL-1201D 0.74 ft³ sealed · 1.31 ft³ ported
FAQ
What box does the Soundstream SPLX-122HX need?
Recommended net volume: 0.71 ft³ sealed, 1.27 ft³ ported tuned to 34 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-122HX Thiele/Small specs?
Fs 31.8 Hz, Qts 0.41, Vas 1.30 ft³, Xmax 0.73″, Sd 79.2 in².
What is the Soundstream SPLX-122HX mounting depth?
Mounting depth is 7″, cutout diameter 11″. The inside depth of the box must exceed the mounting depth by at least 1″.
How much power does the Soundstream SPLX-122HX handle and how do I wire it?
RMS power rating: 1,000 W. Dual 2 Ω voice coils: series gives 4 Ω, parallel gives 1 Ω at the amp. Wiring for several subs and amp power — in the wiring calculator.