Focal K2 Power 33 KX (DVC 2+2 ohm)

13″ subwoofer · dual 2 Ω · 400 W RMS

Fs 39 HzQts 0.73Vas 0.87 ft³Xmax 0.43″

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 volume1.73 ft³ (49 L)
Qtc0.90
Fc48 Hz
F3 (−3 dB, no cabin gain)41 Hz
Example box (outside)14 15/16″ × 14 15/16″ × 18 11/16″
Open sealed box in designer

Ported

Net volume2.93 ft³ (83 L)
Tuning (Fb)30 Hz
Portslot 1 15/16 × 14 5/16″, 24 3/16″ long
Port velocity at 400 W65 ft/s
F3 (−3 dB, no cabin gain)25 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 15 5/8″
Open ported box in designer
203040506080100150200606672788490HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs39 Hz
Qts0.73
Qes0.84
Qms5.77
Vas0.87 ft³
Re (one coil)2.1 Ω
Sd76.1 in²
Xmax0.43″
Vd33 in³ calc.
Mms231 g calc.
BL11.9 T·m calc.
EBP46 — suits sealed calc.
Sensitivity, 1 W / 1 m84.4 dB calc.

General

Size13″
Voice coilsdual 2 Ω
RMS power400 W

Mounting dimensions

Ø13 3/16″cutout ≈ Ø11 7/8″mounting depth 7 1/16″magnet Ø≈ 7 3/4″
Cutout diameter≈ 11 7/8″
Mounting depth7 1/16″
Overall diameter13 3/16″

“≈” 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 Focal 13″ models