For a sedan, one sub, 800 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
29 Hz
Qts
0.52
Qes
0.58
Qms
5.23
Vas
5.97 ft³
Re
3.18 Ω
Sd
126.9 in²
Xmax
0.51″
Vd
65 in³ calc.
Mms
169 g calc.
BL
13 T·m calc.
EBP
50 — sealed or ported calc.
Sensitivity, 1 W / 1 m
90.5 dB calc.
General
Size
15″
Voice coils
4 Ω
RMS power
800 W
Mounting dimensions
Cutout diameter
≈ 13 11/16″
Mounting depth
7 3/8″
Overall diameter
15 3/16″
Magnet diameter
6 1/8″
“≈” 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.