SPL Dynamics V-300D4
12″ subwoofer · dual 4 Ω · 350 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, 350 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 · 0.84 |
|---|---|
| Fc | 47 Hz |
| F3 (−3 dB, no cabin gain) | 42 Hz |
| Example box (outside) | 31 1/2″ × 15 3/4″ × 8 15/16″ |
Ported
deeper, louder| Tuning (Fb) | 34 Hz |
|---|---|
| Port | slot 1 9/16 × 14 5/16″, 24 1/2″ long |
| Port velocity at 350 W | 49 ft/s |
| F3 (−3 dB, no cabin gain) | 33 Hz |
| Example box (outside) | 31 1/2″ × 15 3/4″ × 10 15/16″ |
Deeper: 3.00 ft³ (85 L) tuned to 32 Hz, 31 1/2″ × 15 3/4″ × 15 1/4″ 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 | 12″ |
|---|---|
| Voice coils | dual 4 Ω |
| RMS power | 350 W |
| Fs | 30.7 Hz |
| Qts | 0.55 |
| Qes | 0.616 |
| Qms | 5.46 |
| Vas | 2.31 ft³ |
| Re (one coil) | 3.2 Ω |
|---|---|
| Sd | 77.6 in² |
| Xmax | 0.39″ |
| Vd | 30.6 in³ calc. |
| Mms | 146 g calc. |
| BL | 12.1 T·m calc. |
| EBP | 50 — suits sealed calc. |
| Sensitivity, 1 W / 1 m | 86.9 dB calc. |
Mounting dimensions
| Cutout diameter | 10 3/4″ |
|---|---|
| Mounting depth | 6″ |
| Overall diameter | 12 11/16″ |
Cone area (Sd) calculated from Fs, Vas and Mms: 77.6 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
Other SPL Dynamics 12″ models
- SPL Dynamics PRO-12D2 MK3 12″ · dual 2 Ω
- SPL Dynamics PRO-12D2 MK4 12″ · dual 2 Ω
- SPL Dynamics PRO-12D4 MK3 12″ · dual 4 Ω
- SPL Dynamics PRO-12D4 MK4 12″ · dual 4 Ω
- SPL Dynamics PRO-300D2 12″ · dual 2 Ω
- SPL Dynamics PRO-300D4 12″ · dual 4 Ω
- SPL Dynamics SPL-300D1A 12″ · dual 1 Ω
- SPL Dynamics SPL-300D2 12″ · dual 2 Ω
- SPL Dynamics SW-300D2 12″ · dual 2 Ω
- SPL Dynamics SW-300D4 12″ · dual 4 Ω
- SPL Dynamics V-12S 12″ · 4 Ω
- SPL Dynamics V-12S4 12″ · 4 Ω
Similar 12″ subwoofers from other brands
Close in Fs, Qts and Vas — a box of similar volume will suit them.
- Polk Audio MM2124 DVC 1.84 ft³ sealed · 1.80 ft³ ported
- Spyder Nitro 12 800W S2 1.73 ft³ sealed · 1.77 ft³ ported
- Spyder Nitro 12 800W S4 1.73 ft³ sealed · 1.77 ft³ ported
- JBL Stage 1210 1.87 ft³ sealed · 1.84 ft³ ported
- NVX VCW124v3 1.87 ft³ sealed · 1.87 ft³ ported
- Polk Audio MM2124 1.62 ft³ sealed · 1.80 ft³ ported
FAQ
What box does the SPL Dynamics V-300D4 need?
Recommended net volume: 1.77 ft³ sealed, 1.84 ft³ ported tuned to 34 Hz — for one sub in a sedan at 350 W. Fit the box to your space and amp in the free calculator, with plans and a cut sheet.
What are the SPL Dynamics V-300D4 Thiele/Small specs?
Fs 30.7 Hz, Qts 0.55, Vas 2.31 ft³, Xmax 0.39″, Sd 77.6 in².
What is the SPL Dynamics V-300D4 mounting depth?
Mounting depth is 6″, cutout diameter 10 3/4″. The inside depth of the box must exceed the mounting depth by at least 1″.
How much power does the SPL Dynamics V-300D4 handle and how do I wire it?
RMS power rating: 350 W. Dual 4 Ω voice coils: series gives 8 Ω, parallel gives 2 Ω at the amp. Wiring for several subs and amp power — in the wiring calculator.