Alpine SWG-844 (Type-G)

8″ subwoofer · 4 Ω · 120 W RMS

Fs 34 HzQts 0.42Vas 1.18 ft³Xmax 0.31″

Recommended box

For a sedan, one sub, 120 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 volume0.46 ft³ (13 L)
Qtc0.80
Fc64 Hz
F3 (−3 dB, no cabin gain)61 Hz
Example box (outside)10 1/4″ × 10 1/4″ × 12 3/8″
Open sealed box in designer

Ported

Net volume1.31 ft³ (37 L)
Tuning (Fb)36 Hz
Portslot 1 9/16 × 14 5/16″, 31 11/16″ long
Port velocity at 120 W30 ft/s
F3 (−3 dB, no cabin gain)34 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 9 1/8″
Open ported box in designer
203040506080100150200606672788490HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs34 Hz
Qts0.42
Qes0.46
Qms5.1
Vas1.18 ft³
Re3.6 Ω
Sd33.5 in²
Xmax0.31″
Vd10.5 in³ calc.
Mms43 g calc.
BL8.5 T·m calc.
EBP74 — sealed or ported calc.
Sensitivity, 1 W / 1 m86.6 dB calc.

General

Size8″
Voice coils4 Ω
RMS power120 W

Mounting dimensions

Ø≈ 8 3/8″cutout Ø7 3/16″mounting depth 4 3/8″magnet Ø≈ 4 11/16″
Cutout diameter7 3/16″
Mounting depth4 3/8″

“≈” 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 Alpine 8″ models