Swat SBT-15 v.3

15″ subwoofer · dual 2 Ω · 800 W RMS

Fs 33 HzQts 0.60Vas 2.22 ft³

Recommended box

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

Net volume2.83 ft³ (80 L)
Qtc0.80
Fc44 Hz
F3 (−3 dB, no cabin gain)41 Hz
Example box (outside)31 1/2″ × 18 1/8″ × 11 3/4″
Open sealed box in designer

Ported

Net volume4.80 ft³ (136 L)
Tuning (Fb)29 Hz
Portslot 2 15/16 × 16 11/16″, 26 13/16″ long
Port velocity at 800 W64 ft/s
F3 (−3 dB, no cabin gain)25 Hz
Example box (outside)31 1/2″ × 18 1/8″ × 21 5/8″
Open ported box in designer
203040506080100150200606672788490HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs33 Hz
Qts0.60
Qes0.667
Qms6
Vas2.22 ft³
Re (one coil)≈ 1.7 Ω
Sd≈ 124 in²
Xmax≈ 0.39″
EBP49 — suits sealed calc.
Sensitivity, 1 W / 1 m87.3 dB calc.

General

Size15″
Voice coilsdual 2 Ω
RMS power800 W

Mounting dimensions

Ø15 1/2″cutout Ø14″mounting depth 7 3/16″magnet Ø6 11/16″
Cutout diameter14″
Mounting depth7 3/16″
Overall diameter15 1/2″
Magnet diameter6 11/16″

Only Qts is published — Qms assumed to be 6 and Qes calculated (barely affects box design).

“≈” 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.

Data sources

Other Swat 15″ models