Infinity Reference 1240W

12″ subwoofer · 4 Ω · 300 W RMS

Fs 25.4 HzQts 0.47Vas 2.98 ft³Xmax 0.45″

Recommended box

For a sedan, one sub, 300 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 volume1.55 ft³ (44 L)
Qtc0.80
Fc43 Hz
F3 (−3 dB, no cabin gain)41 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 8 1/16″
Open sealed box in designer

Ported

Net volume3.18 ft³ (90 L)
Tuning (Fb)28 Hz
Portslot 1 9/16 × 14 5/16″, 20 5/16″ long
Port velocity at 300 W64 ft/s
F3 (−3 dB, no cabin gain)26 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 16″
Open ported box in designer
203040506080100150200606672788490HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs25.4 Hz
Qts0.47
Qes0.5
Qms7.62
Vas2.98 ft³
Re3.4 Ω
Sd82.5 in²
Xmax0.45″
Vd37.3 in³ calc.
Mms186 g calc.
BL14.2 T·m calc.
EBP51 — sealed or ported calc.
Sensitivity, 1 W / 1 m86.4 dB calc.

General

Size12″
Voice coils4 Ω
RMS power300 W

Mounting dimensions

Ø12 7/16″cutout Ø11 3/16″mounting depth 5 1/16″magnet Ø≈ 7 1/4″
Cutout diameter11 3/16″
Mounting depth5 1/16″
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 Infinity 12″ models