MTX Audio RT12-04

12″ subwoofer · 4 Ω · 250 W RMS

Fs 28 HzQts 0.53Vas 2.40 ft³Xmax 0.57″

Recommended box

For a sedan, one sub, 250 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 volume1.80 ft³ (51 L)
Qtc0.82
Fc43 Hz
F3 (−3 dB, no cabin gain)40 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 9 1/16″
Open sealed box in designer

Ported

Net volume3.07 ft³ (87 L)
Tuning (Fb)30 Hz
Portslot 1 9/16 × 14 5/16″, 17 7/8″ long
Port velocity at 250 W59 ft/s
F3 (−3 dB, no cabin gain)27 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 15 7/16″
Open ported box in designer
203040506080100150200606672788490HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs28 Hz
Qts0.53
Qes0.58
Qms6.87
Vas2.40 ft³
Re3.2 Ω
Sd79.1 in²
Xmax0.57″
Vd45.1 in³ calc.
Mms175 g calc.
BL13 T·m calc.
EBP48 — suits sealed calc.
Sensitivity, 1 W / 1 m86.1 dB calc.

General

Size12″
Voice coils4 Ω
RMS power250 W

Mounting dimensions

Ø12 7/16″cutout Ø10 15/16″mounting depth 5 5/16″magnet Ø≈ 7 1/8″
Cutout diameter10 15/16″
Mounting depth5 5/16″
Overall diameter12 7/16″

“≈” 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 MTX Audio 12″ models