B2 Audio HNx8 D2

8″ subwoofer · dual 2 Ω · 400 W RMS

Fs 39.3 HzQts 0.46Vas 0.19 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 volume0.32 ft³ (9 L)
Qtc0.58
Fc50 Hz
F3 (−3 dB, no cabin gain)64 Hz
Example box (outside)10 5/8″ × 10 5/8″ × 8 5/8″
Open sealed box in designer

Ported

Net volume0.64 ft³ (18 L)
Tuning (Fb)36 Hz
Portround port Ø2 1/2″, 14 5/16″ long
Port velocity at 400 W197 ft/s
F3 (−3 dB, no cabin gain)31 Hz
Example box (outside)19 1/16″ × 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

Fs39.3 Hz
Qts0.46
Qes0.5
Qms5.64
Vas0.19 ft³
Re (one coil)1.9 Ω
Sd≈ 33.3 in²
Xmax0.59″
EBP79 — sealed or ported calc.
Sensitivity, 1 W / 1 m80.2 dB calc.

General

Size8″
Voice coilsdual 2 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