Fi Audio NEO 3.9 12 D1

12″ subwoofer · dual 1 Ω · 2,500 W RMS

Fs 39.3 HzQts 0.28Vas 0.63 ft³Xmax 1.34″

Recommended box

For a sedan, one sub, 2,500 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 volume0.94 ft³ (26.5 L)
Qtc0.36
Fc51 Hz
F3 (−3 dB, no cabin gain)125 Hz
Example box (outside)14 3/16″ × 14 3/16″ × 12 1/2″
Open sealed box in designer

Ported

Net volume1.41 ft³ (40 L)
Tuning (Fb)30 Hz
Portround port Ø2 1/2″, 8 5/8″ long
Port velocity at 2,500 W686 ft/s
F3 (−3 dB, no cabin gain)110 Hz
Example box (outside)18 5/8″ × 15 3/4″ × 12 3/8″
Open ported box in designer
203040506080100150200606672788490HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs39.3 Hz
Qts0.28
Qes0.29
Qms7.02
Vas0.63 ft³
Re (one coil)0.9 Ω
Sd74.4 in²
Xmax1.34″
Vd99.6 in³ calc.
Mms299 g calc.
BL15.1 T·m calc.
EBP136 — suits ported calc.
Sensitivity, 1 W / 1 m87.7 dB calc.

General

Size12″
Voice coilsdual 1 Ω
RMS power2,500 W

Mounting dimensions

Ø12 1/2″cutout Ø11 1/8″mounting depth 10″magnet Ø≈ 7 1/4″
Cutout diameter11 1/8″
Mounting depth10″
Overall diameter12 1/2″

“≈” 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