Bomber Upgrade Professional 400W 4 Ohm (SW12UP400-4)

12″ subwoofer · 4 Ω · 400 W RMS

23 HzFs, resonance
0.57Qts
7.56 ft³Vas
0.37″Xmax
400 WRMS

Recommended box

For a sedan, one sub, 400 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

smaller, tighter
1.91 ft³ (54 L)
Net volume
Qtc1.27
Fc51 Hz
F3 (−3 dB, no cabin gain)39 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 9 1/2″
Open sealed box in designer

Ported

deeper, louder
3.25 ft³ (92 L)
Net volume
Tuning (Fb)37 Hz
Portslot 1 3/4 × 14 5/16″, 11 1/8″ long
Port velocity at 400 W60 ft/s
F3 (−3 dB, no cabin gain)35 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 15 3/4″
Open ported box in designer
203040506080100150200667278849096HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs23 Hz
Qts0.57
Qes0.66
Qms4.21
Vas7.56 ft³
Re3.29 Ω
Sd84.2 in²
Xmax0.37″
Vd31.5 in³ calc.
Mms93 g calc.
BL8.2 T·m calc.
EBP35 — suits sealed calc.
Sensitivity, 1 W / 1 m88 dB calc.

General

Size12″
Voice coils4 Ω
RMS power400 W

Mounting dimensions

Ø13 1/16″cutout ≈ Ø11 3/4″mounting depth 5 9/16″magnet Ø5 1/4″
Cutout diameter≈ 11 3/4″
Mounting depth5 9/16″
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