Treo SSX18.22

18″ subwoofer · dual 2 Ω · 2,500 W RMS

Fs 22.9 HzQts 0.46Vas 5.93 ft³Xmax 1.10″

Recommended box

For a sedan, one sub, 2,500 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 volume2.93 ft³ (83 L)
Qtc0.80
Fc40 Hz
F3 (−3 dB, no cabin gain)38 Hz
Example box (outside)19 11/16″ × 19 11/16″ × 18 1/16″
Open sealed box in designer

Ported

Net volume6.32 ft³ (179 L)
Tuning (Fb)26 Hz
Portslot 4 1/2 × 19 1/16″, 46 5/16″ long
Port velocity at 2,500 W64 ft/s
F3 (−3 dB, no cabin gain)24 Hz
Example box (outside)31 1/2″ × 20 1/2″ × 29 1/8″
Open ported box in designer
203040506080100150200667278849096HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs22.9 Hz
Qts0.46
Qes0.513
Qms4.41
Vas5.93 ft³
Re (one coil)2 Ω
Sd163.1 in²
Xmax1.10″
Vd179.8 in³ calc.
Mms450 g calc.
BL15.9 T·m calc.
EBP45 — suits sealed calc.
Sensitivity, 1 W / 1 m88 dB calc.

General

Size18″
Voice coilsdual 2 Ω
RMS power2,500 W

Mounting dimensions

Ø18 1/2″cutout Ø16 9/16″mounting depth 9 1/2″magnet Ø≈ 10 3/4″
Cutout diameter16 9/16″
Mounting depth9 1/2″
Overall diameter18 1/2″

“≈” 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