MD.Lab SW-A15
15″ subwoofer · dual 4 Ω · 800 W RMS
Fs 29.3 HzQts 0.60Vas 3.57 ft³
Recommended box
For a sedan, one sub, 800 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 | 2.86 ft³ (81 L) |
|---|---|
| Qtc | 0.89 |
| Fc | 44 Hz |
| F3 (−3 dB, no cabin gain) | 38 Hz |
| Example box (outside) | 31 1/2″ × 18 1/8″ × 11 7/8″ |
Ported
| Net volume | 4.84 ft³ (137 L) |
|---|---|
| Tuning (Fb) | 31 Hz |
| Port | slot 2 9/16 × 16 11/16″, 19 3/16″ long |
| Port velocity at 800 W | 65 ft/s |
| F3 (−3 dB, no cabin gain) | 27 Hz |
| Example box (outside) | 31 1/2″ × 18 1/8″ × 20 5/8″ |
Thiele/Small parameters
| Fs | 29.3 Hz |
|---|---|
| Qts | 0.60 |
| Qes | 0.735 |
| Qms | 3.17 |
| Vas | 3.57 ft³ |
| Re (one coil) | 3.6 Ω |
| Sd | 124.8 in² |
| Xmax | ≈ 0.39″ |
| Mms | 268 g calc. |
| BL | 15.6 T·m calc. |
| EBP | 40 — suits sealed calc. |
| Sensitivity, 1 W / 1 m | 87.4 dB calc. |
General
| Size | 15″ |
|---|---|
| Voice coils | dual 4 Ω |
| RMS power | 800 W |
Mounting dimensions
| Cutout diameter | 14 1/4″ |
|---|---|
| Mounting depth | 9 1/4″ |
| Overall diameter | 15 3/4″ |
Cone area (Sd) calculated from Fs, Vas and Mms: 124.8 in².
Judging by its value, the published Re is for both coils in parallel — converted to per coil.
“≈” 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.