Infinity Primus 1270

12″ subwoofer · 4 Ω · 300 W RMS

Fs 29.7 HzQts 0.49Vas 2.67 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 volume1.59 ft³ (45 L)
Qtc0.80
Fc49 Hz
F3 (−3 dB, no cabin gain)46 Hz
Example box (outside)14 3/16″ × 14 3/16″ × 19 7/16″
Open sealed box in designer

Ported

Net volume3.18 ft³ (90 L)
Tuning (Fb)32 Hz
Portslot 1 3/4 × 14 5/16″, 16 11/16″ long
Port velocity at 300 W59 ft/s
F3 (−3 dB, no cabin gain)29 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

Fs29.7 Hz
Qts0.49
Qes0.56
Qms3.91
Vas2.67 ft³
Re3.6 Ω
Sd82.3 in²
Xmax0.45″
Vd36.9 in³ calc.
Mms151 g calc.
BL13.5 T·m calc.
EBP53 — sealed or ported calc.
Sensitivity, 1 W / 1 m87.5 dB calc.

General

Size12″
Voice coils4 Ω
RMS power300 W

Mounting dimensions

Ø12 1/16″cutout Ø11″mounting depth 5 7/8″magnet Ø≈ 7 1/8″
Cutout diameter11″
Mounting depth5 7/8″
Overall diameter12 1/16″

“≈” 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