Alpine RS-W12D4 (R-Series shallow)
12″ subwoofer · dual 4 Ω · 600 W RMS
Fs 29 HzQts 1.00Vas 1.55 ft³Xmax 0.79″
The published specs don’t add up:
- The spec sheet's Qts 1.49 doesn't match its Qes and Qms (they give 1).
- Sd of 88.7 in² is unusual for a 12″ (typically 63.6–88.4 in²).
Recommended box
For a sedan, one sub, 600 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
| Net volume | 2.01 ft³ (57 L) |
|---|---|
| Qtc | 1.33 |
| Fc | 39 Hz |
| F3 (−3 dB, no cabin gain) | 28 Hz |
| Example box (outside) | 31 1/2″ × 15 3/4″ × 9 15/16″ |
Ported
| Net volume | 3.43 ft³ (97 L) |
|---|---|
| Tuning (Fb) | 30 Hz |
| Port | slot 2 3/8 × 14 5/16″, 24 9/16″ long |
| Port velocity at 600 W | 60 ft/s |
| F3 (−3 dB, no cabin gain) | 24 Hz |
| Example box (outside) | 31 1/2″ × 15 3/4″ × 17 15/16″ |
Thiele/Small parameters
| Fs | 29 Hz |
|---|---|
| Qts | 1.00 |
| Qes | 1.17 |
| Qms | 7.04 |
| Vas | 1.55 ft³ |
| Re (one coil) | 3.6 Ω |
| Sd | 88.7 in² |
| Xmax | 0.79″ |
| Vd | 69.8 in³ calc. |
| Mms | 318 g calc. |
| BL | 13.4 T·m calc. |
| EBP | 25 — suits sealed calc. |
| Sensitivity, 1 W / 1 m | 81.6 dB calc. |
General
| Size | 12″ |
|---|---|
| Voice coils | dual 4 Ω |
| RMS power | 600 W |
Mounting dimensions
| Cutout diameter | 11 5/8″ |
|---|---|
| Mounting depth | 3 1/4″ |
| Overall diameter | 13 9/16″ |
“≈” 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
- manuals.alpine-usa.com/products/documents/OM_R-Shallow_Subs.pdf
- alpine-usa.com/product/r-series-shallow-subwoofer-rsw12d4
Other Alpine 12″ models
- Alpine R-W12D2 12″ · dual 2 Ω
- Alpine R-W12D4 12″ · dual 4 Ω
- Alpine R2-W12D2 12″ · dual 2 Ω
- Alpine R2-W12D4 12″ · dual 4 Ω
- Alpine RS-W12D2 (R-Series shallow) 12″ · dual 2 Ω
- Alpine S-W12D4 12″ · dual 4 Ω
- Alpine S2-W12D2 12″ · dual 2 Ω
- Alpine S2-W12D4 12″ · dual 4 Ω
- Alpine SWA-12S4 (Atom) 12″ · 4 Ω
- Alpine SWE-1243E (Type-E) 12″ · 4 Ω
- Alpine SWE-1244E (Type-E) 12″ · 4 Ω
- Alpine SWG-1244 (Type-G) 12″ · 4 Ω