For a sedan, one sub, 600 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
28.5 Hz
Qts
0.65
Qes
0.73
Qms
5.99
Vas
6.71 ft³
Re
3.6 Ω
Sd
133.3 in²
Xmax
0.39″
Vd
52.5 in³ calc.
Mms
172 g calc.
BL
12.3 T·m calc.
EBP
39 — suits sealed calc.
Sensitivity, 1 W / 1 m
89.8 dB calc.
General
Size
15″
Voice coils
4 Ω
RMS power
600 W
Mounting dimensions
Cutout diameter
≈ 13 11/16″
Mounting depth
6 7/8″
Overall diameter
15 3/16″
Magnet diameter
5 1/4″
“≈” 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.