Bomber Upgrade 400W 4 Ohm (SW8UP400-4)

8″ subwoofer · 4 Ω · 400 W RMS

Fs 45 HzQts 0.93Vas 0.26 ft³Xmax 0.33″

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

Net volume0.53 ft³ (15 L)
Qtc1.14
Fc55 Hz
F3 (−3 dB, no cabin gain)42 Hz
Example box (outside)10 5/8″ × 10 5/8″ × 12 15/16″
Open sealed box in designer

Ported

Net volume1.09 ft³ (31 L)
Tuning (Fb)34 Hz
Port2 round ports Ø2 1/2″, 19 1/4″ long
Port velocity at 400 W125 ft/s
F3 (−3 dB, no cabin gain)28 Hz
Example box (outside)26 7/8″ × 15 3/4″ × 7 1/2″
Open ported box in designer
203040506080100150200606672788490HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs45 Hz
Qts0.93
Qes1.02
Qms11.14
Vas0.26 ft³
Re3.25 Ω
Sd28.4 in²
Xmax0.33″
Vd9.5 in³ calc.
Mms81 g calc.
BL8.5 T·m calc.
EBP44 — suits sealed calc.
Sensitivity, 1 W / 1 m80.2 dB calc.

General

Size8″
Voice coils4 Ω
RMS power400 W

Mounting dimensions

Ø8 1/8″cutout ≈ Ø7 5/16″mounting depth 5 1/16″magnet Ø5 1/4″
Cutout diameter≈ 7 5/16″
Mounting depth5 1/16″
Overall diameter8 1/8″
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 8″ models