American Bass XMAXXX-1822

18″ subwoofer · dual 2 Ω · 4,000 W RMS

Fs 32.5 HzQts 0.44Vas 1.66 ft³Xmax 0.89″

Recommended box

For a sedan, one sub, 4,000 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 volume2.24 ft³ (63.5 L)
Qtc0.58
Fc43 Hz
F3 (−3 dB, no cabin gain)56 Hz
Example box (outside)20 1/16″ × 20 1/16″ × 13 15/16″
Open sealed box in designer

Ported

Net volume3.35 ft³ (95 L)
Tuning (Fb)28 Hz
Portslot 3 1/8 × 19 7/16″, 55 13/16″ long
Port velocity at 4,000 W100 ft/s
F3 (−3 dB, no cabin gain)26 Hz
Example box (outside)31 1/2″ × 20 7/8″ × 19 1/16″
Open ported box in designer
203040506080100150200606672788490HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs32.5 Hz
Qts0.44
Qes0.47
Qms6.17
Vas1.66 ft³
Re (one coil)≈ 1.7 Ω
Sd175.7 in²
Xmax0.89″
Vd155.6 in³ calc.
Mms929 g calc.
BL26.2 T·m calc.
EBP69 — sealed or ported calc.
Sensitivity, 1 W / 1 m87.4 dB calc.

General

Size18″
Voice coilsdual 2 Ω
RMS power4,000 W

Mounting dimensions

Ø≈ 18″cutout Ø16 13/16″mounting depth 11 1/2″magnet Ø≈ 10 15/16″
Cutout diameter16 13/16″
Mounting depth11 1/2″

Cone area (Sd) calculated from Fs, Vas and Mms: 175.7 in².

“≈” 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 American Bass 18″ models