Rockford Fosgate Punch HX2 RFD1212 (2000)

12″ subwoofer · dual 4 Ω · 500 W RMS

Fs 26 HzQts 0.39Vas 4.24 ft³Xmax 0.55″

Recommended box

For a sedan, one sub, 500 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 volume1.31 ft³ (37 L)
Qtc0.80
Fc54 Hz
F3 (−3 dB, no cabin gain)51 Hz
Example box (outside)14 3/16″ × 14 3/16″ × 16 7/16″
Open sealed box in designer

Ported

Net volume2.93 ft³ (83 L)
Tuning (Fb)32 Hz
Portslot 1 15/16 × 14 5/16″, 20 3/4″ long
Port velocity at 500 W64 ft/s
F3 (−3 dB, no cabin gain)31 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 15 5/16″
Open ported box in designer
203040506080100150200667278849096HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs26 Hz
Qts0.39
Qes0.417
Qms6
Vas4.24 ft³
Re (one coil)≈ 3.4 Ω
Sd≈ 76 in²
Xmax0.55″
EBP62 — sealed or ported calc.
Sensitivity, 1 W / 1 m89 dB calc.

General

Size12″
Voice coilsdual 4 Ω
RMS power500 W

Mounting dimensions

Ø≈ 12″cutout Ø10 13/16″mounting depth 5 13/16″magnet Ø≈ 7 1/16″
Cutout diameter10 13/16″
Mounting depth5 13/16″

Only Qts is published — Qms assumed to be 6 and Qes calculated (barely affects box design).

“≈” 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 Rockford Fosgate 12″ models