American Bass HD-1822

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

Fs 35 HzQts 0.72Vas 3.53 ft³Xmax 0.83″
The published specs don’t add up:

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 volume4.31 ft³ (122 L)
Qtc0.97
Fc47 Hz
F3 (−3 dB, no cabin gain)39 Hz
Example box (outside)31 1/2″ × 20 7/8″ × 15″
Open sealed box in designer

Ported

Net volume7.31 ft³ (207 L)
Tuning (Fb)33 Hz
Portslot 4 15/16 × 19 7/16″, 24 1/16″ long
Port velocity at 2,000 W65 ft/s
F3 (−3 dB, no cabin gain)28 Hz
Example box (outside)31 1/2″ × 20 7/8″ × 28 3/16″
Open ported box in designer
203040506080100150200667278849096HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs35 Hz
Qts0.72
Qes0.816
Qms6.07
Vas3.53 ft³
Re (one coil)≈ 1.7 Ω
Sd188.9 in²
Xmax0.83″
Vd156.2 in³ calc.
Mms435 g calc.
BL14.1 T·m calc.
EBP43 — suits sealed calc.
Sensitivity, 1 W / 1 m89.2 dB calc.

General

Size18″
Voice coilsdual 2 Ω
RMS power2,000 W

Mounting dimensions

Ø18 1/2″cutout Ø16 7/8″mounting depth 10 3/8″magnet Ø≈ 10 15/16″
Cutout diameter16 7/8″
Mounting depth10 3/8″
Overall diameter18 1/2″

Cone area (Sd) calculated from Fs, Vas and Mms: 188.9 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