Earthquake Magma-12X

12″ subwoofer · dual 4 Ω · 600 W RMS

Fs 26.4 HzQts 0.60Vas 2.13 ft³Xmax 1.50″

Recommended box

For a sedan, one sub, 600 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

Net volume1.87 ft³ (53 L)
Qtc0.88
Fc39 Hz
F3 (−3 dB, no cabin gain)34 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 9 3/8″
Open sealed box in designer

Ported

Net volume3.18 ft³ (90 L)
Tuning (Fb)28 Hz
Portslot 2 3/16 × 14 5/16″, 28 11/16″ long
Port velocity at 600 W60 ft/s
F3 (−3 dB, no cabin gain)24 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 17 3/16″
Open ported box in designer
203040506080100150200606672788490HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs26.4 Hz
Qts0.60
Qes0.805
Qms2.36
Vas2.13 ft³
Re (one coil)2.9 Ω
Sd82.2 in²
Xmax1.50″
Vd122.9 in³ calc.
Mms241 g calc.
BL12 T·m calc.
EBP33 — suits sealed calc.
Sensitivity, 1 W / 1 m83.4 dB calc.

General

Size12″
Voice coilsdual 4 Ω
RMS power600 W

Mounting dimensions

Ø≈ 12 5/16″cutout Ø11 1/8″mounting depth 6 11/16″magnet Ø≈ 7 1/4″
Cutout diameter11 1/8″
Mounting depth6 11/16″

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

Other Earthquake 12″ models