Ground Zero GZPW Reference 250 (2x2 Ohm)

10″ subwoofer · dual 2 Ω · 500 W RMS

Fs 31 HzQts 0.53Vas 1.11 ft³Xmax 1.57″

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 volume0.88 ft³ (25 L)
Qtc0.80
Fc47 Hz
F3 (−3 dB, no cabin gain)44 Hz
Example box (outside)12 5/8″ × 12 5/8″ × 14 1/2″
Open sealed box in designer

Ported

Net volume2.08 ft³ (59 L)
Tuning (Fb)29 Hz
Portslot 1 3/4 × 14 5/16″, 34 9/16″ long
Port velocity at 500 W65 ft/s
F3 (−3 dB, no cabin gain)26 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 12 3/4″
Open ported box in designer
203040506080100150200606672788490HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs31 Hz
Qts0.53
Qes0.581
Qms6
Vas1.11 ft³
Re (one coil)1.85 Ω
Sd53.4 in²
Xmax1.57″
Vd84.1 in³ calc.
Mms141 g calc.
BL9.3 T·m calc.
EBP53 — sealed or ported calc.
Sensitivity, 1 W / 1 m84.1 dB calc.

General

Size10″
Voice coilsdual 2 Ω
RMS power500 W

Mounting dimensions

Ø≈ 10 7/16″cutout Ø9 1/4″mounting depth 5 1/16″magnet Ø5 9/16″
Cutout diameter9 1/4″
Mounting depth5 1/16″
Magnet diameter5 9/16″

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

Judging by its value, the published Re is for both coils in series — converted to per coil.

“≈” 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 Ground Zero 10″ models