Sundown Audio SML-12 D4

12″ subwoofer · dual 4 Ω · 600 W RMS

Fs 39.9 HzQts 0.51Vas 1.04 ft³Xmax 0.43″

Recommended box

For a sedan, one sub, 600 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 volume0.74 ft³ (21 L)
Qtc0.80
Fc62 Hz
F3 (−3 dB, no cabin gain)59 Hz
Example box (outside)13 3/4″ × 13 3/4″ × 11″
Open sealed box in designer

Ported

Net volume2.30 ft³ (65 L)
Tuning (Fb)34 Hz
Portslot 2 3/16 × 14 5/16″, 26 11/16″ long
Port velocity at 600 W65 ft/s
F3 (−3 dB, no cabin gain)30 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 13 7/16″
Open ported box in designer
203040506080100150200606672788490HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs39.9 Hz
Qts0.51
Qes0.617
Qms3.04
Vas1.04 ft³
Re (one coil)3.43 Ω
Sd76.8 in²
Xmax0.43″
Vd33.3 in³ calc.
Mms187 g calc.
BL16.1 T·m calc.
EBP65 — sealed or ported calc.
Sensitivity, 1 W / 1 m86.8 dB calc.

General

Size12″
Voice coilsdual 4 Ω
RMS power600 W

Mounting dimensions

Ø12 5/8″cutout Ø10 3/4″mounting depth 4 7/16″magnet Ø6 1/8″
Cutout diameter10 3/4″
Mounting depth4 7/16″
Overall diameter12 5/8″
Magnet diameter6 1/8″

The spec sheet's Sd of 114 in² is the area of a 12″ circle, not the cone's radiating area — not used.

Cone area (Sd) calculated from Fs, Vas and Mms: 76.8 in².

“≈” 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 Sundown Audio 12″ models