Sky High Car Audio BMX-12 D2

12″ subwoofer · dual 2 Ω · 2,500 W RMS

25.8 HzFs, resonance

0.42Qts

1.04 ft³Vas

1.26″Xmax

2,500 WRMS

Source	skyhighcaraudio.com · 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, 2,500 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

0.74 ft³ (21 L)

Net volume

Bass character (Qtc)	Flat and accurate · 0.65
Fc	40 Hz
F3 (−3 dB, no cabin gain)	46 Hz
Example box (outside)	14 3/16″ × 14 3/16″ × 10 7/16″

Open sealed box in designer

Ported

deeper, louder

1.13 ft³ (32 L)

Net volume

Tuning (Fb)	34 Hz
Port	2 round ports Ø2 1/2″, 18 9/16″ long
Port velocity at 2,500 W	293 ft/s
F3 (−3 dB, no cabin gain)	30 Hz
Example box (outside)	19 7/8″ × 15 3/4″ × 10 7/16″

At 2,500 W this example’s port will be noisy: air speed 293 ft/s, while the limit is 82 ft/s. It stays quiet up to about 190 W. Full power needs a port of at least 35.6 in², which means a bigger box than this example — size it in the designer.

Open ported box in designer

Deeper: 1.34 ft³ (38 L) tuned to 30 Hz, 22 7/8″ × 15 3/4″ × 10 7/16″ 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	12″
Voice coils	dual 2 Ω
RMS power	2,500 W
Fs	25.8 Hz
Qts	0.42
Qes	0.454
Qms	5.19
Vas	1.04 ft³

Re (one coil)	1.3 Ω
Sd	70.9 in²
Xmax	1.26″
Vd	89.3 in³ calc.
Mms	384 g calc.
BL	13.3 T·m calc.
EBP	57 — sealed or ported calc.
Sensitivity, 1 W / 1 m	82.5 dB calc.

Mounting dimensions

Cutout diameter	11 1/8″
Mounting depth	8″
Overall diameter	12 13/16″

Judging by its value, the published Re is for both coils in series — converted to per coil.

“≈” 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

skyhighcaraudio.com/sky-high-car-audio-bmx-series-12-subwoofer/

Other Sky High Car Audio 12″ models

Sky High Car Audio BMX-12 D1 12″ · dual 1 Ω
Sky High Car Audio FE-12 D2 12″ · dual 2 Ω
Sky High Car Audio FE-12 D4 12″ · dual 4 Ω
Sky High Car Audio FEX-12 D2 12″ · dual 2 Ω
Sky High Car Audio FEX-12 D4 12″ · dual 4 Ω
Sky High Car Audio FMX-12 D1 12″ · dual 1 Ω
Sky High Car Audio FMX-12 D2 12″ · dual 2 Ω
Sky High Car Audio FXB-12 D2 12″ · dual 2 Ω
Sky High Car Audio FXB-12 D4 12″ · dual 4 Ω
Sky High Car Audio FXXL-12 D1 12″ · dual 1 Ω
Sky High Car Audio FXXL-12 D2 12″ · dual 2 Ω

Similar 12″ subwoofers from other brands

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

Sundown Audio Xv1-12 D2 0.90 ft³ sealed · 1.17 ft³ ported
RE Audio XX12 D4 v2 1.06 ft³ sealed · 2.22 ft³ ported
Kicx HeadShot 12 (2+2) 0.72 ft³ sealed · 1.13 ft³ ported
Fi Audio BTL4 12 D1 0.67 ft³ sealed · 1.20 ft³ ported
Fi Audio BTL4 12 D2 0.67 ft³ sealed · 1.20 ft³ ported
AMP MASS 1000 12D2 V.2 0.71 ft³ sealed · 2.33 ft³ ported

FAQ

What box does the Sky High Car Audio BMX-12 D2 need?

Recommended net volume: 0.74 ft³ sealed, 1.13 ft³ ported tuned to 34 Hz — for one sub in a sedan at 2,500 W. Fit the box to your space and amp in the free calculator, with plans and a cut sheet.

What are the Sky High Car Audio BMX-12 D2 Thiele/Small specs?

Fs 25.8 Hz, Qts 0.42, Vas 1.04 ft³, Xmax 1.26″, Sd 70.9 in².

What is the Sky High Car Audio BMX-12 D2 mounting depth?

Mounting depth is 8″, cutout diameter 11 1/8″. The inside depth of the box must exceed the mounting depth by at least 1″.

How much power does the Sky High Car Audio BMX-12 D2 handle and how do I wire it?

RMS power rating: 2,500 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.