Earthquake Pro-X184

18″ subwoofer · 4 Ω · 800 W RMS

Fs 36 HzQts 0.67Vas 13.63 ft³Xmax 0.98″

Recommended box

For a sedan, one sub, 800 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 volume4.13 ft³ (117 L)
Qtc1.40
Fc75 Hz
F3 (−3 dB, no cabin gain)55 Hz
Example box (outside)31 1/2″ × 20 7/8″ × 14 7/16″
Open sealed box in designer

Ported

Net volume6.99 ft³ (198 L)
Tuning (Fb)50 Hz
Portslot 2 15/16 × 19 7/16″, 2 1/2″ long
Port velocity at 800 W61 ft/s
F3 (−3 dB, no cabin gain)48 Hz
Example box (outside)31 1/2″ × 20 7/8″ × 23 1/8″
Open ported box in designer
20304050608010015020078849096102108HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs36 Hz
Qts0.67
Qes0.732
Qms8.44
Vas13.63 ft³
Re3.5 Ω
Sd≈ 180.6 in²
Xmax0.98″
EBP49 — suits sealed calc.
Sensitivity, 1 W / 1 m95.9 dB calc.

General

Size18″
Voice coils4 Ω
RMS power800 W

Mounting dimensions

Ø18 3/4″cutout Ø16 15/16″mounting depth 7 11/16″magnet Ø≈ 11″
Cutout diameter16 15/16″
Mounting depth7 11/16″
Overall diameter18 3/4″

“≈” 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