Pride UFO.4 12 D0.7

12″ subwoofer · dual 0.7 Ω · 5,000 W RMS

Fs 35 HzQts 0.12Vas 0.95 ft³Xmax 1.57″
The published specs don’t add up:

Recommended box

For a sedan, one sub, 5,000 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 volume0.94 ft³ (26.5 L)
Qtc0.17
Fc50 Hz
F3 (−3 dB, no cabin gain)250 Hz
Example box (outside)14 9/16″ × 14 9/16″ × 11 13/16″
Open sealed box in designer

Ported

Net volume1.59 ft³ (45 L)
Tuning (Fb)26 Hz
Port2 round ports Ø2 1/2″, 23″ long
Port velocity at 5,000 W481 ft/s
F3 (−3 dB, no cabin gain)250 Hz
Example box (outside)23 3/8″ × 15 3/4″ × 11 13/16″
Open ported box in designer
203040506080100150200606672788490HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs35 Hz
Qts0.12
Qes0.122
Qms6
Vas0.95 ft³
Re (one coil)2.8 Ω
Sd83.5 in²
Xmax1.57″
Vd131.6 in³ calc.
Mms315 g calc.
BL39.9 T·m calc.
EBP287 — suits ported calc.
Sensitivity, 1 W / 1 m91.8 dB calc.

General

Size12″
Voice coilsdual 0.7 Ω
RMS power5,000 W

Mounting dimensions

Ø≈ 12 3/8″cutout Ø11 1/4″mounting depth 9 3/8″magnet Ø≈ 7 5/16″
Cutout diameter11 1/4″
Mounting depth9 3/8″

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 12″ models