Pride SS.5 18 Competition D0.7 (SS.518compD07)

18″ subwoofer · dual 0.7 Ω · 5,500 W RMS

Fs 20.9 HzQts 0.21Vas 5.93 ft³Xmax 1.42″
The published specs don’t add up:

Recommended box

For a sedan, one sub, 5,500 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 volume2.42 ft³ (68.5 L)
Qtc0.38
Fc39 Hz
F3 (−3 dB, no cabin gain)88 Hz
Example box (outside)20 1/16″ × 20 1/16″ × 14 13/16″
Open sealed box in designer

Ported

Net volume3.78 ft³ (107 L)
Tuning (Fb)25 Hz
Portslot 2 15/16 × 19 7/16″, 58 3/4″ long
Port velocity at 5,500 W122 ft/s
F3 (−3 dB, no cabin gain)73 Hz
Example box (outside)31 1/2″ × 20 7/8″ × 20 5/16″
Open ported box in designer
203040506080100150200606672788490HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs20.9 Hz
Qts0.21
Qes0.214
Qms6
Vas5.93 ft³
Re (one coil)0.7 Ω
Sd196.9 in²
Xmax1.42″
Vd279 in³ calc.
Mms789 g calc.
BL18.4 T·m calc.
EBP98 — sealed or ported calc.
Sensitivity, 1 W / 1 m90.6 dB calc.

General

Size18″
Voice coilsdual 0.7 Ω
RMS power5,500 W

Mounting dimensions

Ø≈ 18 1/8″cutout Ø16 15/16″mounting depth 12 3/8″magnet Ø13″
Cutout diameter16 15/16″
Mounting depth12 3/8″
Magnet diameter13″

Only Qts is published — Qms assumed to be 6 and Qes calculated (barely affects box design).

“≈” 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 Pride 18″ models