Hertz Uno S 300 S4 (SVC 4 ohm)

12″ subwoofer · 4 Ω · 250 W RMS

Fs 33 HzQts 0.60Vas 2.90 ft³Xmax 0.36″

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 volume1.84 ft³ (52 L)
Qtc0.96
Fc53 Hz
F3 (−3 dB, no cabin gain)45 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 9 3/16″
Open sealed box in designer

Ported

Net volume3.14 ft³ (89 L)
Tuning (Fb)37 Hz
Portslot 1 9/16 × 14 5/16″, 10 1/8″ long
Port velocity at 250 W61 ft/s
F3 (−3 dB, no cabin gain)33 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 15 1/8″
Open ported box in designer
203040506080100150200667278849096HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs33 Hz
Qts0.60
Qes0.65
Qms7.8
Vas2.90 ft³
Re3.6 Ω
Sd81 in²
Xmax0.36″
Vd29 in³ calc.
Mms110 g calc.
BL11.2 T·m calc.
EBP51 — sealed or ported calc.
Sensitivity, 1 W / 1 m88.6 dB calc.

General

Size12″
Voice coils4 Ω
RMS power250 W

Mounting dimensions

Ø12 1/16″cutout Ø11″mounting depth 4 3/4″magnet Ø4 1/2″
Cutout diameter11″
Mounting depth4 3/4″
Overall diameter12 1/16″
Magnet diameter4 1/2″

“≈” 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 Hertz 12″ models