Sundown Audio NSv4-18 D1
18″ subwoofer · dual 1 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 · 0.57 |
|---|---|
| Fc | 46 Hz |
| F3 (−3 dB, no cabin gain) | 61 Hz |
| Example box (outside) | 19 11/16″ × 19 11/16″ × 17 11/16″ |
Ported
deeper, louder| Tuning (Fb) | 34 Hz |
|---|---|
| Port | slot 5 7/8 × 19 1/16″, 41″ long |
| Port velocity at 3,000 W | 64 ft/s |
| F3 (−3 dB, no cabin gain) | 31 Hz |
| Example box (outside) | 31 1/2″ × 20 1/2″ × 26 3/4″ |
Deeper: 3.39 ft³ (96 L) tuned to 33 Hz, 29 1/4″ × 20 1/2″ × 22 7/16″ 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 1 Ω |
| RMS power | 3,000 W |
| Fs | 30.9 Hz |
| Qts | 0.39 |
| Qes | 0.421 |
| Qms | 4.52 |
| Vas | 3.44 ft³ |
| Re (one coil) | 0.65 Ω |
|---|---|
| Sd | 176.9 in² |
| Xmax | ≈ 0.39″ |
| Mms | 503 g calc. |
| BL | 12.3 T·m calc. |
| EBP | 73 — 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: 176.9 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 D2 18″ · dual 2 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.
- Ascendant Audio TEAM 18 D1 2.30 ft³ sealed · 5.54 ft³ ported
- Ascendant Audio TEAM 18 D2 2.30 ft³ sealed · 5.54 ft³ ported
- Fi Audio MT 18 D1 2.38 ft³ sealed · 3.00 ft³ ported
- Fi Audio TEAM 18 D1 2.30 ft³ sealed · 3.00 ft³ ported
- Fi Audio TEAM v2 18 D1 2.38 ft³ sealed · 3.00 ft³ ported
- Pride BB V.2 18 1.87 ft³ sealed · 2.97 ft³ ported
FAQ
What box does the Sundown Audio NSv4-18 D1 need?
Recommended net volume: 2.86 ft³ sealed, 5.23 ft³ ported tuned to 34 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 D1 Thiele/Small specs?
Fs 30.9 Hz, Qts 0.39, Vas 3.44 ft³, Sd 176.9 in².
What is the Sundown Audio NSv4-18 D1 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 D1 handle and how do I wire it?
RMS power rating: 3,000 W. Dual 1 Ω voice coils: series gives 2 Ω, parallel gives 0.5 Ω at the amp. Wiring for several subs and amp power — in the wiring calculator.