For a sedan, one sub, 400 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 Hz
Qts
0.68
Qes
0.76
Qms
6.7
Vas
0.99 ft³
Re (one coil)
3.1 Ω
Sd
50.7 in²
Xmax
0.67″
Vd
33.9 in³ calc.
Mms
143 g calc.
BL
10.6 T·m calc.
EBP
41 — suits sealed calc.
Sensitivity, 1 W / 1 m
82.4 dB calc.
General
Size
10″
Voice coils
dual 4 Ω
RMS power
400 W
Mounting dimensions
Cutout diameter
9 3/16″
Mounting depth
4 1/4″
Overall diameter
10 5/8″
“≈” 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.