Bomber Upgrade 375W 4 Ohm (SW12UP-375-4)

12″ subwoofer · 4 Ω · 375 W RMS

Fs 29.5 HzQts 0.69Vas 3.20 ft³Xmax 0.37″

Recommended box

For a sedan, one sub, 375 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 volume1.91 ft³ (54 L)
Qtc1.13
Fc48 Hz
F3 (−3 dB, no cabin gain)38 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 9 1/2″
Open sealed box in designer

Ported

Net volume3.25 ft³ (92 L)
Tuning (Fb)36 Hz
Portslot 1 3/4 × 14 5/16″, 11 15/16″ long
Port velocity at 375 W64 ft/s
F3 (−3 dB, no cabin gain)32 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 15 13/16″
Open ported box in designer
203040506080100150200667278849096HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs29.5 Hz
Qts0.69
Qes0.78
Qms6.1
Vas3.20 ft³
Re3.24 Ω
Sd84.2 in²
Xmax0.37″
Vd31.5 in³ calc.
Mms134 g calc.
BL10.2 T·m calc.
EBP38 — suits sealed calc.
Sensitivity, 1 W / 1 m86.7 dB calc.

General

Size12″
Voice coils4 Ω
RMS power375 W

Mounting dimensions

Ø13 1/16″cutout ≈ Ø11 3/4″mounting depth 6 1/4″magnet Ø5 1/4″
Cutout diameter≈ 11 3/4″
Mounting depth6 1/4″
Overall diameter13 1/16″
Magnet diameter5 1/4″

“≈” 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 Bomber 12″ models