Ascendant Audio SMD V2 15 D2
15″ subwoofer · dual 2 Ω · 5,000 W RMS
The Ascendant Audio SMD V2 15 D2 is a 15″ subwoofer. With Qts 0.27 and EBP 122 it suits a ported box: deeper and louder; sealed, the bass sounds a bit dry. Long excursion (Xmax 1.38″) — built for loud music and high power.
| 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, 5,000 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 · 0.33 |
|---|---|
| Fc | 42 Hz |
| F3 (−3 dB, no cabin gain) | 115 Hz |
| Example box (outside) | 17 5/16″ × 17 5/16″ × 16 3/4″ |
Ported
deeper, louder| Tuning (Fb) | 34 Hz |
|---|---|
| Port | slot 5 7/8 × 16 11/16″, 53 1/4″ long |
| Port velocity at 5,000 W | 83 ft/s |
| F3 (−3 dB, no cabin gain) | 88 Hz |
| Example box (outside) | 31 1/2″ × 18 1/8″ × 26 1/16″ |
At 5,000 W this example’s port will be noisy: air speed 83 ft/s, while the limit is 82 ft/s. It stays quiet up to about 4,800 W. Full power needs a port of at least 100.3 in², which means a bigger box than this example — size it in the designer.
Open ported box in designerDeeper: 2.40 ft³ (68 L) tuned to 26 Hz, 22 1/4″ × 18 1/8″ × 21 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 | 5,000 W |
| Fs | 34.1 Hz |
| Qts | 0.27 |
| Qes | 0.28 |
| Qms | 5.87 |
| Vas | 1.11 ft³ |
| Re (one coil) | 1.4 Ω |
|---|---|
| Sd | 125.6 in² |
| Xmax | 1.38″ |
| Vd | 173 in³ calc. |
| Mms | 643 g calc. |
| BL | 26.3 T·m calc. |
| EBP | 122 — suits ported calc. |
| Sensitivity, 1 W / 1 m | 88.5 dB calc. |
Mounting dimensions
| Cutout diameter | 14 1/8″ |
|---|---|
| Mounting depth | 14 1/4″ |
| Overall diameter | 15 5/8″ |
“≈” 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/20150301210607/http://ascendantaudio.com:80/products/smd/
- web.archive.org/web/20170115195531/http://ascendantaudio.com/products/smd/
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 |
|---|---|---|---|---|---|---|
| Ascendant Audio SMD V2 15 D1 | dual 1 Ω | 0.7 Ω | 0.28 | 1.11 ft³ | 2.07 ft³ | 3.71 ft³ · 34 Hz |
| Ascendant Audio SMD V2 15 D2 | dual 2 Ω | 1.4 Ω | 0.28 | 1.11 ft³ | 2.07 ft³ | 3.71 ft³ · 34 Hz |
Other Ascendant Audio 15″ models
- Ascendant Audio Chaos 15 D1 15″ · dual 1 Ω
- Ascendant Audio Chaos 15 D2 15″ · dual 2 Ω
- Ascendant Audio Havoc 15 D1 15″ · dual 1 Ω
- Ascendant Audio Havoc 15 D2 15″ · dual 2 Ω
- Ascendant Audio Mayhem 15 D1 15″ · dual 1 Ω
- Ascendant Audio Mayhem 15 D2 15″ · dual 2 Ω
- Ascendant Audio SMD Signature 15 D1 15″ · dual 1 Ω
- Ascendant Audio SMD Signature 15 D2 15″ · dual 2 Ω
- Ascendant Audio TEAM 15 D1 15″ · dual 1 Ω
- Ascendant Audio TEAM 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.
- Deaf Bonce Apocalypse DB-455-NEO D1 1.84 ft³ sealed · 3.67 ft³ ported
- Sundown Audio NSv4-15 D2 1.82 ft³ sealed · 3.35 ft³ ported
- Fi Audio OMEGA 15 D1 1.66 ft³ sealed · 3.71 ft³ ported
- Fi Audio OMEGA 15 D2 1.66 ft³ sealed · 3.71 ft³ ported
- Ground Zero GZPW 15SPL (1x2 Ohm) 1.54 ft³ sealed · 2.47 ft³ ported
- Sundown Audio NSv4-15 D1 1.82 ft³ sealed · 3.35 ft³ ported
- Fi Audio BTL3 15 D1 1.25 ft³ sealed · 3.71 ft³ ported
- Fi Audio BTL3 15 D2 1.25 ft³ sealed · 3.71 ft³ ported
- Fi Audio HC 15 D1 1.25 ft³ sealed · 3.71 ft³ ported
FAQ
What box does the Ascendant Audio SMD V2 15 D2 need?
Recommended net volume: 2.07 ft³ sealed, 3.71 ft³ ported tuned to 34 Hz — for one sub in a sedan at 5,000 W. Fit the box to your space and amp in the free calculator, with plans and a cut sheet.
What are the Ascendant Audio SMD V2 15 D2 Thiele/Small specs?
Fs 34.1 Hz, Qts 0.27, Vas 1.11 ft³, Xmax 1.38″, Sd 125.6 in².
What is the Ascendant Audio SMD V2 15 D2 mounting depth?
Mounting depth is 14 1/4″, cutout diameter 14 1/8″. The inside depth of the box must exceed the mounting depth by at least 1″.
How much power does the Ascendant Audio SMD V2 15 D2 handle and how do I wire it?
RMS power rating: 5,000 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.
Is the Ascendant Audio SMD V2 15 D2 better sealed or ported?
EBP 122: a ported box (3.71 ft³, tuned to 34 Hz) suits it best — deeper and louder. Sealed (2.07 ft³) the bass is drier.
What port does the Ascendant Audio SMD V2 15 D2 need?
For the 3.71 ft³ ported box tuned to 34 Hz: slot 5 7/8 × 16 11/16″, 53 1/4″ long, area 98.6 in²; or a round port Ø11 3/16″, ≈ 53 1/4″ long. Port air speed at 5,000 W: 83 ft/s.
What box do two Ascendant Audio SMD V2 15 D2 subs need?
Two subs need twice the volume: 4.13 ft³ sealed, or 7.42 ft³ ported at the same 34 Hz tuning with twice the port area. One shared chamber or one per sub — whatever fits your vehicle.