DC Audio Level 3 M3 18 D4

18″ subwoofer · dual 4 Ω · 1,000 W RMS

Fs 30.4 HzQts 0.66Vas 6.55 ft³Xmax 0.91″

Recommended box

For a sedan, one sub, 1,000 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 volume4.31 ft³ (122 L)
Qtc1.05
Fc48 Hz
F3 (−3 dB, no cabin gain)39 Hz
Example box (outside)31 1/2″ × 20 7/8″ × 15″
Open sealed box in designer

Ported

Net volume7.31 ft³ (207 L)
Tuning (Fb)35 Hz
Portslot 3 3/8 × 19 7/16″, 12 3/4″ long
Port velocity at 1,000 W63 ft/s
F3 (−3 dB, no cabin gain)31 Hz
Example box (outside)31 1/2″ × 20 7/8″ × 25 1/2″
Open ported box in designer
2030405060801001502007278849096102HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs30.4 Hz
Qts0.66
Qes0.718
Qms8.32
Vas6.55 ft³
Re (one coil)≈ 3.4 Ω
Sd188.6 in²
Xmax0.91″
Vd170.8 in³ calc.
Mms310 g calc.
BL16.7 T·m calc.
EBP42 — suits sealed calc.
Sensitivity, 1 W / 1 m90.6 dB calc.

General

Size18″
Voice coilsdual 4 Ω
RMS power1,000 W

Mounting dimensions

Ø18 1/2″cutout Ø16 3/4″mounting depth 9 1/2″magnet Ø≈ 10 7/8″
Cutout diameter16 3/4″
Mounting depth9 1/2″
Overall diameter18 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 DC Audio 18″ models