Alpine S2-W8D2

8″ subwoofer · dual 2 Ω · 300 W RMS

Fs 46.5 HzQts 0.58Vas 0.25 ft³Xmax 0.51″

Recommended box

For a sedan, one sub, 300 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 volume0.28 ft³ (8 L)
Qtc0.80
Fc64 Hz
F3 (−3 dB, no cabin gain)60 Hz
Example box (outside)9 13/16″ × 9 13/16″ × 9 1/8″
Open sealed box in designer

Ported

Net volume0.81 ft³ (23 L)
Tuning (Fb)35 Hz
Portround port Ø2 1/2″, 11 9/16″ long
Port velocity at 300 W184 ft/s
F3 (−3 dB, no cabin gain)31 Hz
Example box (outside)24 7/8″ × 15 3/4″ × 6 1/8″
Open ported box in designer
2030405060801001502006066727884HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs46.5 Hz
Qts0.58
Qes0.65
Qms5.6
Vas0.25 ft³
Re (one coil)1.8 Ω
Sd30.1 in²
Xmax0.51″
Vd15.4 in³ calc.
Mms87 g calc.
BL8.4 T·m calc.
EBP72 — sealed or ported calc.
Sensitivity, 1 W / 1 m82.5 dB calc.

General

Size8″
Voice coilsdual 2 Ω
RMS power300 W

Mounting dimensions

Ø8 9/16″cutout Ø6 7/8″mounting depth 3 11/16″magnet Ø≈ 4 7/16″
Cutout diameter6 7/8″
Mounting depth3 11/16″
Overall diameter8 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

Other Alpine 8″ models