SPL Dynamics PRO-15D2 MK4

15″ subwoofer · dual 2 Ω · 700 W RMS

37.5 HzFs, resonance

0.42Qts

2.39 ft³Vas

0.67″Xmax

700 WRMS

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, 700 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

1.20 ft³ (34 L)

Net volume

Bass character (Qtc)	Flat and accurate · 0.73
Fc	65 Hz
F3 (−3 dB, no cabin gain)	66 Hz
Example box (outside)	16 15/16″ × 16 15/16″ × 11 5/16″

Open sealed box in designer

Ported

deeper, louder

2.12 ft³ (60 L)

Net volume

Tuning (Fb)	34 Hz
Port	slot 1 3/4 × 16 5/16″, 27 1/16″ long
Port velocity at 700 W	65 ft/s
F3 (−3 dB, no cabin gain)	39 Hz
Example box (outside)	31 1/2″ × 17 11/16″ × 11 5/8″

Open ported box in designer

Deeper: 3.07 ft³ (87 L) tuned to 37 Hz, 31 1/2″ × 17 11/16″ × 15″ outside — a bigger box with flatter deep bass. Open in the calculator

Where to buy Amazon

Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Size	15″
Voice coils	dual 2 Ω
RMS power	700 W
Fs	37.5 Hz
Qts	0.42
Qes	0.45
Qms	7.28
Vas	2.39 ft³

Re (one coil)	1.8 Ω
Sd	133 in²
Xmax	0.67″
Vd	89 in³ calc.
Mms	277 g calc.
BL	16.2 T·m calc.
EBP	83 — sealed or ported calc.
Sensitivity, 1 W / 1 m	91 dB calc.

Mounting dimensions

Cutout diameter	13 7/8″
Mounting depth	7 1/2″

Cone area (Sd) calculated from Fs, Vas and Mms: 133 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/20070718034538/http://www.spldynamics.fi:80/oldmodels/oldsub

Other SPL Dynamics 15″ models

SPL Dynamics PRO-15D2 MK3 15″ · dual 2 Ω
SPL Dynamics PRO-15D4 MK3 15″ · dual 4 Ω
SPL Dynamics PRO-15D4 MK4 15″ · dual 4 Ω
SPL Dynamics PRO-380D2 15″ · dual 2 Ω
SPL Dynamics PRO-380D4 15″ · dual 4 Ω
SPL Dynamics SPL-380D1A 15″ · dual 1 Ω
SPL Dynamics SPL-380D2 15″ · dual 2 Ω
SPL Dynamics XTR-380D2S 15″ · dual 2 Ω
SPL Dynamics XTR-380D4S 15″ · dual 4 Ω

Similar 15″ subwoofers from other brands

Close in Fs, Qts and Vas — a box of similar volume will suit them.

Audioque HDC315-A D1 1.27 ft³ sealed · 2.19 ft³ ported
Soundstream SPLX-152 (2006) 1.13 ft³ sealed · 1.98 ft³ ported
Bomber Bicho Papão 2000W 2+2 Ohm (SW15BP-2000-2+2) 1.27 ft³ sealed · 2.05 ft³ ported
Fi Audio SSD NEO 15 D1 1.31 ft³ sealed · 2.01 ft³ ported
Fi Audio SSD NEO 15 D2 1.31 ft³ sealed · 2.01 ft³ ported
ESX VE1522 (2x2 Ohm) 1.48 ft³ sealed · 3.88 ft³ ported

FAQ

What box does the SPL Dynamics PRO-15D2 MK4 need?

Recommended net volume: 1.20 ft³ sealed, 2.12 ft³ ported tuned to 34 Hz — for one sub in a sedan at 700 W. Fit the box to your space and amp in the free calculator, with plans and a cut sheet.

What are the SPL Dynamics PRO-15D2 MK4 Thiele/Small specs?

Fs 37.5 Hz, Qts 0.42, Vas 2.39 ft³, Xmax 0.67″, Sd 133 in².

What is the SPL Dynamics PRO-15D2 MK4 mounting depth?

Mounting depth is 7 1/2″, cutout diameter 13 7/8″. The inside depth of the box must exceed the mounting depth by at least 1″.

How much power does the SPL Dynamics PRO-15D2 MK4 handle and how do I wire it?

RMS power rating: 700 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.