Massive Audio H124X

12″ subwoofer · dual 4 Ω · 2,000 W RMS

Fs 38 HzQts 0.37Vas 0.84 ft³Xmax 0.81″

Recommended box

For a sedan, one sub, 2,000 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

Net volume0.78 ft³ (22 L)
Qtc0.53
Fc55 Hz
F3 (−3 dB, no cabin gain)81 Hz
Example box (outside)14 3/16″ × 14 3/16″ × 10 13/16″
Open sealed box in designer

Ported

Net volume1.59 ft³ (45 L)
Tuning (Fb)32 Hz
Portround port Ø2 1/2″, 6 3/8″ long
Port velocity at 2,000 W603 ft/s
F3 (−3 dB, no cabin gain)31 Hz
Example box (outside)23 3/8″ × 15 3/4″ × 10 13/16″
Open ported box in designer
203040506080100150200606672788490HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs38 Hz
Qts0.37
Qes0.43
Qms2.48
Vas0.84 ft³
Re (one coil)3.2 Ω
Sd82.2 in²
Xmax0.81″
Vd66.3 in³ calc.
Mms292 g calc.
BL22.8 T·m calc.
EBP88 — sealed or ported calc.
Sensitivity, 1 W / 1 m86.8 dB calc.

General

Size12″
Voice coilsdual 4 Ω
RMS power2,000 W

Mounting dimensions

Ø12 11/16″cutout Ø11 1/8″mounting depth 8 3/8″magnet Ø≈ 7 3/16″
Cutout diameter11 1/8″
Mounting depth8 3/8″
Overall diameter12 11/16″

“≈” 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 Massive Audio 12″ models