Genius Audio V4-M8D4

8″ subwoofer · dual 4 Ω · 400 W RMS

Fs 52.2 HzQts 0.51Vas 0.12 ft³Xmax 0.59″

Recommended box

For a sedan, one sub, 400 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)
Qtc0.61
Fc62 Hz
F3 (−3 dB, no cabin gain)75 Hz
Example box (outside)10 5/8″ × 10 5/8″ × 7 7/8″
Open sealed box in designer

Ported

Net volume0.57 ft³ (16 L)
Tuning (Fb)41 Hz
Portround port Ø2 1/2″, 12 3/16″ long
Port velocity at 400 W203 ft/s
F3 (−3 dB, no cabin gain)36 Hz
Example box (outside)16 5/8″ × 15 3/4″ × 6 1/2″
Open ported box in designer
2030405060801001502006066727884HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs52.2 Hz
Qts0.51
Qes0.54
Qms10.34
Vas0.12 ft³
Re (one coil)4 Ω
Sd30.4 in²
Xmax0.59″
Vd17.9 in³ calc.
Mms149 g calc.
BL19 T·m calc.
EBP97 — sealed or ported calc.
Sensitivity, 1 W / 1 m81.5 dB calc.

General

Size8″
Voice coilsdual 4 Ω
RMS power400 W

Mounting dimensions

Ø≈ 8 1/2″cutout ≈ Ø7 5/16″mounting depth ≈ 3 15/16″magnet Ø≈ 4 3/4″
Cutout diameter≈ 7 5/16″
Mounting depth≈ 3 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