Alpine X-W12D4

12″ subwoofer · dual 4 Ω · 900 W RMS

Fs 27 HzQts 0.56Vas 1.98 ft³Xmax 0.94″

Recommended box

For a sedan, one sub, 900 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 volume1.70 ft³ (48 L)
Qtc0.82
Fc40 Hz
F3 (−3 dB, no cabin gain)37 Hz
Example box (outside)14 3/16″ × 14 3/16″ × 20 9/16″
Open sealed box in designer

Ported

Net volume2.86 ft³ (81 L)
Tuning (Fb)28 Hz
Portslot 2 9/16 × 14 5/16″, 38 11/16″ long
Port velocity at 900 W65 ft/s
F3 (−3 dB, no cabin gain)25 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 17 3/8″
Open ported box in designer
203040506080100150200606672788490HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs27 Hz
Qts0.56
Qes0.62
Qms5.63
Vas1.98 ft³
Re (one coil)3.6 Ω
Sd73.6 in²
Xmax0.94″
Vd69.6 in³ calc.
Mms198 g calc.
BL14 T·m calc.
EBP44 — suits sealed calc.
Sensitivity, 1 W / 1 m84.5 dB calc.

General

Size12″
Voice coilsdual 4 Ω
RMS power900 W

Mounting dimensions

Ø12 15/16″cutout Ø11 1/16″mounting depth 7 1/4″magnet Ø≈ 7 3/16″
Cutout diameter11 1/16″
Mounting depth7 1/4″
Overall diameter12 15/16″

“≈” 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

Other Alpine 12″ models