Soundstream XXX-15

15″ subwoofer · 1 Ω · 9,000 W RMS

24.6 HzFs, resonance

0.18Qts

3.22 ft³Vas

0.98″Xmax

9,000 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

The published specs don’t add up:

This sub has 4 voice coils — wiring options are calculated as for a single coil; check the final impedance against the spec sheet.

Recommended box

For a sedan, one sub, 9,000 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

1.39 ft³ (39.5 L)

Net volume

Bass character (Qtc)	Dry and tight · 0.33
Fc	45 Hz
F3 (−3 dB, no cabin gain)	123 Hz
Example box (outside)	17 5/16″ × 17 5/16″ × 12 1/8″

Open sealed box in designer

Ported

deeper, louder

3.53 ft³ (100 L)

Net volume

Tuning (Fb)	30 Hz
Port	slot 5 1/8 × 16 11/16″, 64 1/4″ long
Port velocity at 9,000 W	121 ft/s
F3 (−3 dB, no cabin gain)	112 Hz
Example box (outside)	31 1/2″ × 18 1/8″ × 26 3/16″

At 9,000 W this example’s port will be noisy: air speed 121 ft/s, while the limit is 82 ft/s. It stays quiet up to about 4,100 W. Full power needs a port of at least 125.8 in², which means a bigger box than this example — size it in the designer.

Open ported box in designer

Deeper: 2.30 ft³ (65 L) tuned to 27 Hz, 31 1/2″ × 18 1/8″ × 14″ 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	1 Ω
RMS power	9,000 W
Fs	24.6 Hz
Qts	0.18
Qes	0.187
Qms	5.78
Vas	3.22 ft³

Re	1.2 Ω
Sd	119.2 in²
Xmax	0.98″
Vd	117.3 in³ calc.
Mms	384 g calc.
BL	19.5 T·m calc.
EBP	132 — suits ported calc.
Sensitivity, 1 W / 1 m	90.6 dB calc.

Mounting dimensions

Cutout diameter	14 1/4″
Mounting depth	9 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/20241206221935/https://www.soundstream.com/manuals/2009/XXX%

Other Soundstream 15″ models

Soundstream PCW-15 15″ · dual 4 Ω
Soundstream PWS-15 15″ · dual 4 Ω
Soundstream PXW-15 15″ · dual 4 Ω
Soundstream PXW-15/2 15″ · dual 2 Ω
Soundstream R1-15 15″ · dual 4 Ω
Soundstream R1-15L 15″ · dual 4 Ω
Soundstream R3.15 15″ · dual 2 Ω
Soundstream RBW-15 15″ · dual 4 Ω
Soundstream SPLX-152 ('07-'08) 15″ · dual 2 Ω
Soundstream SPLX-152 (2006) 15″ · dual 2 Ω
Soundstream SPLX-152HX 15″ · dual 2 Ω
Soundstream SPLX-154 ('07-'08) 15″ · 4 Ω

Similar 15″ subwoofers from other brands

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

Pride ST 15 D0.5 1.61 ft³ sealed · 4.06 ft³ ported
VM Audio ECW150 1.22 ft³ sealed · 3.57 ft³ ported
Pride S V.3 15 D1 1.59 ft³ sealed · 4.17 ft³ ported
Pride S V.3 15 D2 1.59 ft³ sealed · 4.17 ft³ ported
Cerwin-Vega Mobile ST152D (Stroker 15" DVC 2ohm) 1.36 ft³ sealed · 2.01 ft³ ported
Pride UFO.5 15 D0.7 1.75 ft³ sealed · 4.10 ft³ ported

FAQ

What box does the Soundstream XXX-15 need?

Recommended net volume: 1.39 ft³ sealed, 3.53 ft³ ported tuned to 30 Hz — for one sub in a sedan at 9,000 W. Fit the box to your space and amp in the free calculator, with plans and a cut sheet.

What are the Soundstream XXX-15 Thiele/Small specs?

Fs 24.6 Hz, Qts 0.18, Vas 3.22 ft³, Xmax 0.98″, Sd 119.2 in².

What is the Soundstream XXX-15 mounting depth?

Mounting depth is 9 5/8″, cutout diameter 14 1/4″. The inside depth of the box must exceed the mounting depth by at least 1″.

How much power does the Soundstream XXX-15 handle and how do I wire it?

RMS power rating: 9,000 W. Wiring for several subs and amp power — in the wiring calculator.