Rockford Fosgate Punch P1S2-15

15″ subwoofer · 2 Ω · 250 W RMS

Fs 23 HzQts 0.65Vas 6.76 ft³Xmax 0.35″
The published specs don’t add up:

Recommended box

For a sedan, one sub, 250 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 volume3.11 ft³ (88 L)
Qtc1.16
Fc41 Hz
F3 (−3 dB, no cabin gain)32 Hz
Example box (outside)31 1/2″ × 17 11/16″ × 13″
Open sealed box in designer

Ported

Net volume5.26 ft³ (149 L)
Tuning (Fb)31 Hz
Portslot 1 9/16 × 16 5/16″, 9 3/8″ long
Port velocity at 250 W57 ft/s
F3 (−3 dB, no cabin gain)28 Hz
Example box (outside)31 1/2″ × 17 11/16″ × 21 1/4″
Open ported box in designer
203040506080100150200667278849096HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs23 Hz
Qts0.65
Qes0.8
Qms3.46
Vas6.76 ft³
Re1.8 Ω
Sd135.8 in²
Xmax0.35″
Vd48.1 in³ calc.
Mms272 g calc.
BL9.4 T·m calc.
EBP29 — suits sealed calc.
Sensitivity, 1 W / 1 m86.6 dB calc.

General

Size15″
Voice coils2 Ω
RMS power250 W

Mounting dimensions

Ø≈ 15 1/16″cutout Ø13 7/8″mounting depth 6 15/16″magnet Ø≈ 9″
Cutout diameter13 7/8″
Mounting depth6 15/16″

“≈” 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 Rockford Fosgate 15″ models