For a sedan, one sub, 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 Ported · SPL in dB at 1 W / 1 m, no cabin gain
Thiele/Small parameters
Fs
31.5 Hz
Qts
0.54
Qes
0.571
Qms
10.42
Vas
1.95 ft³
Re (one coil)
1.9 Ω
Sd
82.3 in²
Xmax
0.69″
Vd
56.7 in³ calc.
Mms
185 g calc.
BL
11 T·m calc.
EBP
55 — sealed or ported calc.
Sensitivity, 1 W / 1 m
86.8 dB calc.
General
Size
12″
Voice coils
dual 2 Ω
RMS power
500 W
Mounting dimensions
Cutout diameter
11″
Mounting depth
5 3/4″
Magnet diameter
5 7/8″
“≈” 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.