Massive Audio H124XR

12″ subwoofer · dual 4 Ω · 3,000 W RMS

Fs 43.1 HzQts 0.41Vas 0.59 ft³Xmax 0.85″

Recommended box

For a sedan, one sub, 3,000 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 volume0.83 ft³ (23.5 L)
Qtc0.54
Fc56 Hz
F3 (−3 dB, no cabin gain)82 Hz
Example box (outside)14 3/16″ × 14 3/16″ × 11 3/8″
Open sealed box in designer

Ported

Net volume1.59 ft³ (45 L)
Tuning (Fb)33 Hz
Portround port Ø2 1/2″, 5 7/8″ long
Port velocity at 3,000 W794 ft/s
F3 (−3 dB, no cabin gain)31 Hz
Example box (outside)22 1/16″ × 15 3/4″ × 11 7/16″
Open ported box in designer
203040506080100150200606672788490HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs43.1 Hz
Qts0.41
Qes0.471
Qms3.12
Vas0.59 ft³
Re (one coil)3.2 Ω
Sd82.2 in²
Xmax0.85″
Vd69.9 in³ calc.
Mms322 g calc.
BL24.3 T·m calc.
EBP91 — sealed or ported calc.
Sensitivity, 1 W / 1 m86.6 dB calc.

General

Size12″
Voice coilsdual 4 Ω
RMS power3,000 W

Mounting dimensions

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