SoundQubed HDX418 D1

18″ subwoofer · dual 1 Ω · 2,000 W RMS

Fs 22.8 HzQts 0.44Vas 5.77 ft³Xmax 1.22″

Recommended box

For a sedan, one sub, 2,000 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 volume2.47 ft³ (70 L)
Qtc0.80
Fc42 Hz
F3 (−3 dB, no cabin gain)40 Hz
Example box (outside)19 11/16″ × 19 11/16″ × 15 11/16″
Open sealed box in designer

Ported

Net volume7.31 ft³ (207 L)
Tuning (Fb)25 Hz
Portslot 4 1/2 × 19 1/16″, 42 13/16″ long
Port velocity at 2,000 W64 ft/s
F3 (−3 dB, no cabin gain)23 Hz
Example box (outside)31 1/2″ × 20 1/2″ × 31 1/2″
Open ported box in designer
203040506080100150200667278849096HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs22.8 Hz
Qts0.44
Qes0.485
Qms4.57
Vas5.77 ft³
Re (one coil)≈ 0.85 Ω
Sd188.7 in²
Xmax1.22″
Vd230.3 in³ calc.
Mms626 g calc.
BL12.5 T·m calc.
EBP47 — suits sealed calc.
Sensitivity, 1 W / 1 m88 dB calc.

General

Size18″
Voice coilsdual 1 Ω
RMS power2,000 W

Mounting dimensions

Ø≈ 17 3/4″cutout Ø16 9/16″mounting depth 11 5/8″magnet Ø≈ 10 3/4″
Cutout diameter16 9/16″
Mounting depth11 5/8″

“≈” 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 SoundQubed 18″ models