Sundown Audio NSv4-18 D2
18″ subwoofer · dual 2 Ω · 3,000 W RMS
| Source | web.archive.org · manufacturer data |
|---|---|
| Checked against source | October 2026 |
| Thiele/Small parameters | not in the spec sheet: Xmax — typical value for the size used |
| Mounting dimensions | 3 of 4 — missing: magnet diameter; the designer will use an estimate |
Recommended box
For a sedan, one sub, 3,000 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
smaller, tighter| Bass character (Qtc) | Dry and tight · 0.51 |
|---|---|
| Fc | 42 Hz |
| F3 (−3 dB, no cabin gain) | 66 Hz |
| Example box (outside) | 19 11/16″ × 19 11/16″ × 17 11/16″ |
Ported
deeper, louder| Tuning (Fb) | 30 Hz |
|---|---|
| Port | slot 5 1/2 × 19 1/16″, 51 1/4″ long |
| Port velocity at 3,000 W | 64 ft/s |
| F3 (−3 dB, no cabin gain) | 28 Hz |
| Example box (outside) | 31 1/2″ × 20 1/2″ × 28 3/16″ |
Deeper: 3.39 ft³ (96 L) tuned to 31 Hz, 31 1/2″ × 20 1/2″ × 21 3/8″ outside — a bigger box with flatter deep bass. Open in the calculator
Projects with this subwoofer
Boxes that users designed and published: plans, cut sheet and response graph.
Thiele/Small parameters
| Size | 18″ |
|---|---|
| Voice coils | dual 2 Ω |
| RMS power | 3,000 W |
| Fs | 26.7 Hz |
| Qts | 0.32 |
| Qes | 0.35 |
| Qms | 3.94 |
| Vas | 4.36 ft³ |
| Re (one coil) | 1.43 Ω |
|---|---|
| Sd | 176.9 in² |
| Xmax | ≈ 0.39″ |
| Mms | 532 g calc. |
| BL | 19.1 T·m calc. |
| EBP | 76 — sealed or ported calc. |
| Sensitivity, 1 W / 1 m | 90.3 dB calc. |
Mounting dimensions
| Cutout diameter | 16 11/16″ |
|---|---|
| Mounting depth | 15 1/4″ |
| Overall diameter | 18 7/16″ |
Cone area (Sd) calculated from Fs, Vas and Mms: 177 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
- web.archive.org/web/20191212161612/https://sundownaudio.com/index.php/products/s
- web.archive.org/web/20210425002706/https://sundownaudio.com/lv/sa/subwoofers/ns-
Other Sundown Audio 18″ models
- Sundown Audio Inhuman-18 D1 18″ · dual 1 Ω
- Sundown Audio M18 D1 18″ · dual 1 Ω
- Sundown Audio M18 D2 18″ · dual 2 Ω
- Sundown Audio NSv1-18 D1 18″ · dual 1 Ω
- Sundown Audio NSv2-18 D2 18″ · dual 2 Ω
- Sundown Audio NSv4-18 D1 18″ · dual 1 Ω
- Sundown Audio NSv5-18 D1 18″ · dual 1 Ω
- Sundown Audio NSv5-18 D2 18″ · dual 2 Ω
- Sundown Audio NSv6-18 D1 18″ · dual 1 Ω
- Sundown Audio NSv6-18 D2 18″ · dual 2 Ω
- Sundown Audio SAv2-18 D2 18″ · dual 2 Ω
- Sundown Audio SAv2-18 D4 18″ · dual 4 Ω
Similar 18″ subwoofers from other brands
Close in Fs, Qts and Vas — a box of similar volume will suit them.
- Edge EDX18D1SPL-E7 1.62 ft³ sealed · 5.33 ft³ ported
- Pride T V.3 18 D1 1.92 ft³ sealed · 5.33 ft³ ported
- Pride T V.3 18 D2 1.92 ft³ sealed · 5.33 ft³ ported
- Edge EDX18D1-E7 1.62 ft³ sealed · 5.33 ft³ ported
- URAL Patriot 18 (2+2) 1.62 ft³ sealed · 5.33 ft³ ported
- SPL Dynamics SPL-460D2 1.92 ft³ sealed · 5.62 ft³ ported
FAQ
What box does the Sundown Audio NSv4-18 D2 need?
Recommended net volume: 2.86 ft³ sealed, 5.23 ft³ ported tuned to 30 Hz — for one sub in a sedan at 3,000 W. Fit the box to your space and amp in the free calculator, with plans and a cut sheet.
What are the Sundown Audio NSv4-18 D2 Thiele/Small specs?
Fs 26.7 Hz, Qts 0.32, Vas 4.36 ft³, Sd 176.9 in².
What is the Sundown Audio NSv4-18 D2 mounting depth?
Mounting depth is 15 1/4″, cutout diameter 16 11/16″. The inside depth of the box must exceed the mounting depth by at least 1″.
How much power does the Sundown Audio NSv4-18 D2 handle and how do I wire it?
RMS power rating: 3,000 W. Dual 2 Ω voice coils: series gives 4 Ω, parallel gives 1 Ω at the amp. Wiring for several subs and amp power — in the wiring calculator.