Sundown Audio Zv4-18 D2
18″ subwoofer · dual 2 Ω · 1,750 W RMS
| Source | web.archive.org · manufacturer data |
|---|---|
| Checked against source | October 2026 |
| Thiele/Small parameters | complete |
| Mounting dimensions | 3 of 4 — missing: magnet diameter; the designer will use an estimate |
Recommended box
For a sedan, one sub, 1,750 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) | Tight and punchy · 0.80 |
|---|---|
| Fc | 41 Hz |
| F3 (−3 dB, no cabin gain) | 38 Hz |
| Example box (outside) | 31 1/2″ × 20 1/2″ × 14 7/16″ |
Ported
deeper, louder| Tuning (Fb) | 30 Hz |
|---|---|
| Port | slot 2 3/4 × 19 1/16″, 34 9/16″ long |
| Port velocity at 1,750 W | 65 ft/s |
| F3 (−3 dB, no cabin gain) | 29 Hz |
| Example box (outside) | 31 1/2″ × 20 1/2″ × 17 11/16″ |
Deeper: 6.96 ft³ (197 L) tuned to 28 Hz, 31 1/2″ × 20 1/2″ × 28 1/2″ 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 | 1,750 W |
| Fs | 27.4 Hz |
| Qts | 0.54 |
| Qes | 0.6 |
| Qms | 5.39 |
| Vas | 4.81 ft³ |
| Re (one coil) | 1.8 Ω |
|---|---|
| Sd | 179.3 in² |
| Xmax | 1.38″ |
| Vd | 247.1 in³ calc. |
| Mms | 470 g calc. |
| BL | 15.6 T·m calc. |
| EBP | 46 — suits sealed calc. |
| Sensitivity, 1 W / 1 m | 88.7 dB calc. |
Mounting dimensions
| Cutout diameter | 16 11/16″ |
|---|---|
| Mounting depth | 11 3/8″ |
| Overall diameter | 18 7/16″ |
Cone area (Sd) calculated from Fs, Vas and Mms: 179.3 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/20190808023357/http://sundownaudio.com/index.php/products/di
- web.archive.org/web/20190807024731/http://sundownaudio.com/index.php/subwoofers/
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 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
Similar 18″ subwoofers from other brands
Close in Fs, Qts and Vas — a box of similar volume will suit them.
- Ascendant Audio Havoc 18 D2 4.27 ft³ sealed · 3.88 ft³ ported
- Skar Audio ZVX-18v2 D2 3.43 ft³ sealed · 5.26 ft³ ported
- Kicker Solo-Baric L7X 18" 1-Ohm DVC (49L7X181) 4.20 ft³ sealed · 7.52 ft³ ported
- Ascendant Audio Havoc 18 D1 4.27 ft³ sealed · 3.92 ft³ ported
- DC Audio XL-Elite 18 D1 4.10 ft³ sealed · 3.64 ft³ ported
- DC Audio XL-Elite 18 D2 4.10 ft³ sealed · 3.64 ft³ ported
FAQ
What box does the Sundown Audio Zv4-18 D2 need?
Recommended net volume: 4.03 ft³ sealed, 3.85 ft³ ported tuned to 30 Hz — for one sub in a sedan at 1,750 W. Fit the box to your space and amp in the free calculator, with plans and a cut sheet.
What are the Sundown Audio Zv4-18 D2 Thiele/Small specs?
Fs 27.4 Hz, Qts 0.54, Vas 4.81 ft³, Xmax 1.38″, Sd 179.3 in².
What is the Sundown Audio Zv4-18 D2 mounting depth?
Mounting depth is 11 3/8″, 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 Zv4-18 D2 handle and how do I wire it?
RMS power rating: 1,750 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.