Sundown Audio Xv1-15 D2
15″ subwoofer · dual 2 Ω · 1,250 W RMS
The Sundown Audio Xv1-15 D2 is a 15″ subwoofer. With Qts 0.43 and EBP 49 it suits a sealed box: tight bass in a small enclosure; a ported box would need a lot of volume. Long excursion (Xmax 1.18″) — built for loud music and high power.
| Source | web.archive.org · manufacturer data |
|---|---|
| Checked against source | October 2026 |
| Thiele/Small parameters | complete |
| Mounting dimensions | 2 of 4 — missing: frame outer diameter, magnet diameter; the designer will use an estimate |
Recommended box
For a sedan, one sub, 1,250 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) | Flat and accurate · 0.77 |
|---|---|
| Fc | 41 Hz |
| F3 (−3 dB, no cabin gain) | 40 Hz |
| Example box (outside) | 16 15/16″ × 16 15/16″ × 13 5/16″ |
Ported
deeper, louder| Tuning (Fb) | 30 Hz |
|---|---|
| Port | slot 2 9/16 × 16 5/16″, 42 3/4″ long |
| Port velocity at 1,250 W | 64 ft/s |
| F3 (−3 dB, no cabin gain) | 28 Hz |
| Example box (outside) | 31 1/2″ × 17 11/16″ × 15 9/16″ |
Deeper: 4.31 ft³ (122 L) tuned to 25 Hz, 31 1/2″ × 17 11/16″ × 23 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 | 15″ |
|---|---|
| Voice coils | dual 2 Ω |
| RMS power | 1,250 W |
| Fs | 22.9 Hz |
| Qts | 0.43 |
| Qes | 0.47 |
| Qms | 5.11 |
| Vas | 3.22 ft³ |
| Re (one coil) | 1.9 Ω |
|---|---|
| Sd | 116.2 in² |
| Xmax | 1.18″ |
| Vd | 137.3 in³ calc. |
| Mms | 422 g calc. |
| BL | 15.7 T·m calc. |
| EBP | 49 — suits sealed calc. |
| Sensitivity, 1 W / 1 m | 85.7 dB calc. |
Mounting dimensions
| Cutout diameter | 13 13/16″ |
|---|---|
| Mounting depth | 10 7/8″ |
Where it fits in a vehicle
Spots from our vehicle guides where the cutout, mounting depth and recommended box fit. The spot sizes are approximate — measure your own vehicle.
- Excursion — behind the third row sealed and ported box
- Club Car Precedent — under the rear seat sealed box
Cone area (Sd) calculated from Fs, Vas and Mms: 116.2 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/20190807034628/http://sundownaudio.com/index.php/products/di
- web.archive.org/web/20210125011608/https://sundownaudio.com/lv/sa/discontinued/d
Voice coil versions
The same sub with different voice coils: the parameters are nearly the same — pick by your amp and wiring.
| Model | Voice coils | Re | Qes | Vas | Sealed | Ported |
|---|---|---|---|---|---|---|
| Sundown Audio Xv1-15 D2 | dual 2 Ω | 1.9 Ω | 0.47 | 3.22 ft³ | 1.48 ft³ | 2.58 ft³ · 30 Hz |
| Sundown Audio Xv1-15 D4 | dual 4 Ω | 3.05 Ω | 0.61 | 3.19 ft³ | 2.65 ft³ | 2.54 ft³ · 30 Hz |
Other Sundown Audio 15″ models
- Sundown Audio Ev2-15 D2 15″ · dual 2 Ω
- Sundown Audio Ev2-15 D4 15″ · dual 4 Ω
- Sundown Audio Ev4-15 D2 15″ · dual 2 Ω
- Sundown Audio Ev4-15 D4 15″ · dual 4 Ω
- Sundown Audio M15 D1 15″ · dual 1 Ω
- Sundown Audio M15 D2 15″ · dual 2 Ω
- Sundown Audio NSv1-15 D2 15″ · dual 2 Ω
- Sundown Audio NSv2-15 D2 15″ · dual 2 Ω
- Sundown Audio NSv4-15 D1 15″ · dual 1 Ω
- Sundown Audio NSv4-15 D2 15″ · dual 2 Ω
- Sundown Audio NSv6-15 D1 15″ · dual 1 Ω
- Sundown Audio NSv6-15 D2 15″ · dual 2 Ω
Similar 15″ subwoofers from other brands
Close in Fs, Qts and Vas — a box of similar volume will suit them.
- AMP MASS 800 15D2 V.2 1.34 ft³ sealed · 2.83 ft³ ported
- Alpine SWR-1542D (Type-R) 1.66 ft³ sealed · 2.83 ft³ ported
- Diamond HXP152 1.36 ft³ sealed · 2.40 ft³ ported
- Diamond HXP154 1.59 ft³ sealed · 2.40 ft³ ported
- Rockford Fosgate Power T215D4 (2004) 1.34 ft³ sealed · 2.51 ft³ ported
- RE Audio XX15 D2 v2 1.77 ft³ sealed · 2.86 ft³ ported
FAQ
What box does the Sundown Audio Xv1-15 D2 need?
Recommended net volume: 1.48 ft³ sealed, 2.58 ft³ ported tuned to 30 Hz — for one sub in a sedan at 1,250 W. Fit the box to your space and amp in the free calculator, with plans and a cut sheet.
What are the Sundown Audio Xv1-15 D2 Thiele/Small specs?
Fs 22.9 Hz, Qts 0.43, Vas 3.22 ft³, Xmax 1.18″, Sd 116.2 in².
What is the Sundown Audio Xv1-15 D2 mounting depth?
Mounting depth is 10 7/8″, cutout diameter 13 13/16″. The inside depth of the box must exceed the mounting depth by at least 1″.
How much power does the Sundown Audio Xv1-15 D2 handle and how do I wire it?
RMS power rating: 1,250 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.
Is the Sundown Audio Xv1-15 D2 better sealed or ported?
EBP 49: a sealed box (1.48 ft³) suits it best — tight bass in a compact enclosure. Ported is possible (2.58 ft³, tuned to 30 Hz) but larger.
What port does the Sundown Audio Xv1-15 D2 need?
For the 2.58 ft³ ported box tuned to 30 Hz: slot 2 9/16 × 16 5/16″, 42 3/4″ long, area 41.7 in²; or a round port Ø7 5/16″, ≈ 42 3/4″ long. Port air speed at 1,250 W: 64 ft/s.
What box do two Sundown Audio Xv1-15 D2 subs need?
Two subs need twice the volume: 2.97 ft³ sealed, or 5.16 ft³ ported at the same 30 Hz tuning with twice the port area. One shared chamber or one per sub — whatever fits your vehicle.