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
41.4 Hz
Qts
0.64
Qes
0.688
Qms
9.7
Vas
0.69 ft³
Re (one coil)
3.51 Ω
Sd
53.7 in²
Xmax
0.69″
Vd
37 in³ calc.
Mms
128 g calc.
BL
13 T·m calc.
EBP
60 — sealed or ported calc.
Sensitivity, 1 W / 1 m
85.1 dB calc.
General
Size
10″
Voice coils
dual 4 Ω
RMS power
400 W
Mounting dimensions
Cutout diameter
9 1/8″
Mounting depth
5 1/4″
Magnet diameter
5 3/4″
“≈” 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.