Fi Audio Alpha 12 S4

12″ subwoofer · 4 Ω · 600 W RMS

Fs 32.4 HzQts 0.56Vas 1.54 ft³Xmax 0.67″

Recommended box

For a sedan, one sub, 600 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 volume1.52 ft³ (43 L)
Qtc0.80
Fc46 Hz
F3 (−3 dB, no cabin gain)43 Hz
Example box (outside)14 3/16″ × 14 3/16″ × 18 11/16″
Open sealed box in designer

Ported

Net volume2.90 ft³ (82 L)
Tuning (Fb)30 Hz
Portslot 2 3/8 × 14 5/16″, 29 15/16″ long
Port velocity at 600 W63 ft/s
F3 (−3 dB, no cabin gain)26 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 16 3/8″
Open ported box in designer
203040506080100150200606672788490HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs32.4 Hz
Qts0.56
Qes0.61
Qms7.17
Vas1.54 ft³
Re3.1 Ω
Sd74.4 in²
Xmax0.67″
Vd49.8 in³ calc.
Mms180 g calc.
BL13.7 T·m calc.
EBP53 — sealed or ported calc.
Sensitivity, 1 W / 1 m85.9 dB calc.

General

Size12″
Voice coils4 Ω
RMS power600 W

Mounting dimensions

Ø≈ 12 5/16″cutout ≈ Ø11 1/8″mounting depth ≈ 5 7/8″magnet Ø≈ 7 3/16″
Cutout diameter≈ 11 1/8″
Mounting depth≈ 5 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 Fi Audio 12″ models