AMPIRE FLAT12

12″ subwoofer · 4 Ω · 350 W RMS

Fs 24.6 HzQts 0.60Vas 2.80 ft³Xmax 0.39″

Recommended box

For a sedan, one sub, 350 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 volume1.80 ft³ (51 L)
Qtc0.96
Fc39 Hz
F3 (−3 dB, no cabin gain)33 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 9 1/16″
Open sealed box in designer

Ported

Net volume3.07 ft³ (87 L)
Tuning (Fb)29 Hz
Portslot 1 9/16 × 14 5/16″, 19 7/16″ long
Port velocity at 350 W64 ft/s
F3 (−3 dB, no cabin gain)26 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 15 1/2″
Open ported box in designer
203040506080100150200606672788490HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs24.6 Hz
Qts0.60
Qes0.684
Qms4.98
Vas2.80 ft³
Re3.6 Ω
Sd79.1 in²
Xmax0.39″
Vd31.1 in³ calc.
Mms196 g calc.
BL12.6 T·m calc.
EBP36 — suits sealed calc.
Sensitivity, 1 W / 1 m84.3 dB calc.

General

Size12″
Voice coils4 Ω
RMS power350 W

Mounting dimensions

Ø12 7/16″cutout Ø10 7/8″mounting depth 3 11/16″magnet Ø≈ 7 1/16″
Cutout diameter10 7/8″
Mounting depth3 11/16″
Overall diameter12 7/16″

“≈” 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 AMPIRE 12″ models