CT Sounds HYDRO-12 D4

12″ subwoofer · dual 4 Ω · 500 W RMS

Fs 36.8 HzQts 0.48Vas 1.28 ft³Xmax 0.43″

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 volume0.71 ft³ (20 L)
Qtc0.80
Fc62 Hz
F3 (−3 dB, no cabin gain)58 Hz
Example box (outside)14 3/16″ × 14 3/16″ × 10 1/16″
Open sealed box in designer

Ported

Net volume2.33 ft³ (66 L)
Tuning (Fb)33 Hz
Portslot 2 3/16 × 14 5/16″, 28 1/16″ long
Port velocity at 500 W60 ft/s
F3 (−3 dB, no cabin gain)30 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 13 3/4″
Open ported box in designer
203040506080100150200606672788490HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs36.8 Hz
Qts0.48
Qes0.526
Qms5.44
Vas1.28 ft³
Re (one coil)3.2 Ω
Sd79.2 in²
Xmax0.43″
Vd34.3 in³ calc.
Mms191 g calc.
BL16.4 T·m calc.
EBP70 — sealed or ported calc.
Sensitivity, 1 W / 1 m87.4 dB calc.

General

Size12″
Voice coilsdual 4 Ω
RMS power500 W

Mounting dimensions

Ø12 13/16″cutout Ø11 1/8″mounting depth 4 1/2″magnet Ø≈ 7 3/16″
Cutout diameter11 1/8″
Mounting depth4 1/2″
Overall diameter12 13/16″

“≈” 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 CT Sounds 12″ models