For a sedan, one sub, 1,500 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
25 Hz
Qts
1.20
Qes
1.491
Qms
6.15
Vas
2.52 ft³
Re (one coil)
≈ 3.4 Ω
Sd
≈ 124 in²
Xmax
0.61″
EBP
17 — suits sealed calc.
Sensitivity, 1 W / 1 m
80.7 dB calc.
General
Size
15″
Voice coils
dual 4 Ω
RMS power
1,500 W
Mounting dimensions
Cutout diameter
≈ 14″
Mounting depth
8 13/16″
“≈” 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.