Soundstream R3.12
12″ subwoofer · dual 2 Ω · 1,200 W RMS
Fs 33.7 HzQts 0.99Vas 2.12 ft³
The published specs don’t add up:
- Fs, Vas and Sd don't match the moving mass of 281.2842 g (they give 126 g) — one of the spec sheet values is probably wrong.
Recommended box
For a sedan, one sub, 1,200 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 | 1.73 ft³ (49 L) |
|---|---|
| Qtc | 1.47 |
| Fc | 50 Hz |
| F3 (−3 dB, no cabin gain) | 36 Hz |
| Example box (outside) | 14 15/16″ × 14 15/16″ × 18 11/16″ |
Ported
| Net volume | 2.93 ft³ (83 L) |
|---|---|
| Tuning (Fb) | 39 Hz |
| Port | slot 2 15/16 × 14 5/16″, 20″ long |
| Port velocity at 1,200 W | 64 ft/s |
| F3 (−3 dB, no cabin gain) | 32 Hz |
| Example box (outside) | 31 1/2″ × 15 3/4″ × 15 7/8″ |
Thiele/Small parameters
| Fs | 33.7 Hz |
|---|---|
| Qts | 0.99 |
| Qes | 1.174 |
| Qms | 6.22 |
| Vas | 2.12 ft³ |
| Re (one coil) | 2.17 Ω |
| Sd | ≈ 76 in² |
| Xmax | ≈ 0.39″ |
| EBP | 29 — suits sealed calc. |
| Sensitivity, 1 W / 1 m | 84.9 dB calc. |
General
| Size | 12″ |
|---|---|
| Voice coils | dual 2 Ω |
| RMS power | 1,200 W |
Mounting dimensions
| Cutout diameter | 11 5/8″ |
|---|---|
| Mounting depth | 6 7/8″ |
“≈” 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 T5.122 12″ · dual 2 Ω