Helix K 8W-SVC2 (1x2 Ohm)

8″ subwoofer · 2 Ω · 300 W RMS

37 HzFs, resonance
0.44Qts
0.47 ft³Vas
0.31″Xmax
300 WRMS

Recommended box

For a sedan, one sub, 300 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

smaller, tighter
0.32 ft³ (9 L)
Net volume
Qtc0.69
Fc58 Hz
F3 (−3 dB, no cabin gain)63 Hz
Example box (outside)10 1/4″ × 10 1/4″ × 9 1/4″
Open sealed box in designer

Ported

deeper, louder
0.67 ft³ (19 L)
Net volume
Tuning (Fb)36 Hz
Portround port Ø2 1/2″, 13 1/2″ long
Port velocity at 300 W155 ft/s
F3 (−3 dB, no cabin gain)33 Hz
Example box (outside)19 13/16″ × 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

Fs37 Hz
Qts0.44
Qes0.49
Qms4.01
Vas0.47 ft³
Re2 Ω
Sd33.9 in²
Xmax0.31″
Vd10.7 in³ calc.
Mms94 g calc.
BL9.4 T·m calc.
EBP76 — sealed or ported calc.
Sensitivity, 1 W / 1 m83.4 dB calc.

General

Size8″
Voice coils2 Ω
RMS power300 W

Mounting dimensions

Ø8 7/16″cutout Ø7 3/16″mounting depth 4″magnet Ø≈ 4 11/16″
Cutout diameter7 3/16″
Mounting depth4″
Overall diameter8 7/16″

“≈” 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

Other Helix 8″ models