Sundown Audio NSv6-18 D1

18″ subwoofer · dual 1 Ω · 3,500 W RMS

Fs 28.6 HzQts 0.45Vas 2.79 ft³Xmax 1.38″

Recommended box

For a sedan, one sub, 3,500 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 volume3.07 ft³ (87 L)
Qtc0.63
Fc39 Hz
F3 (−3 dB, no cabin gain)47 Hz
Example box (outside)19 11/16″ × 19 11/16″ × 18 13/16″
Open sealed box in designer

Ported

Net volume4.31 ft³ (122 L)
Tuning (Fb)28 Hz
Portslot 4 15/16 × 19 1/16″, 66 3/16″ long
Port velocity at 3,500 W66 ft/s
F3 (−3 dB, no cabin gain)25 Hz
Example box (outside)31 1/2″ × 20 1/2″ × 27 1/4″
Open ported box in designer
203040506080100150200606672788490HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs28.6 Hz
Qts0.45
Qes0.496
Qms5.21
Vas2.79 ft³
Re (one coil)0.91 Ω
Sd176.8 in²
Xmax1.38″
Vd243.6 in³ calc.
Mms723 g calc.
BL15.4 T·m calc.
EBP58 — sealed or ported calc.
Sensitivity, 1 W / 1 m87.7 dB calc.

General

Size18″
Voice coilsdual 1 Ω
RMS power3,500 W

Mounting dimensions

Ø18 5/8″cutout Ø16 11/16″mounting depth 16 5/16″magnet Ø7 7/8″
Cutout diameter16 11/16″
Mounting depth16 5/16″
Overall diameter18 5/8″
Magnet diameter7 7/8″

The spec sheet's Sd of 254.5 in² is the area of a 18″ circle, not the cone's radiating area — not used.

Cone area (Sd) calculated from Fs, Vas and Mms: 176.8 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 18″ models