Pioneer TS-W309D4

12″ subwoofer · dual 4 Ω · 400 W RMS

Fs 37.2 HzQts 0.81Vas 1.19 ft³Xmax 0.45″

Recommended box

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

Net volume1.73 ft³ (49 L)
Qtc1.05
Fc48 Hz
F3 (−3 dB, no cabin gain)38 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 8 3/4″
Open sealed box in designer

Ported

Net volume2.93 ft³ (83 L)
Tuning (Fb)33 Hz
Portslot 1 15/16 × 14 5/16″, 19 1/4″ long
Port velocity at 400 W63 ft/s
F3 (−3 dB, no cabin gain)27 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 15 3/16″
Open ported box in designer
203040506080100150200606672788490HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs37.2 Hz
Qts0.81
Qes0.936
Qms6
Vas1.19 ft³
Re (one coil)≈ 3.4 Ω
Sd≈ 76 in²
Xmax0.45″
EBP40 — suits sealed calc.
Sensitivity, 1 W / 1 m84.7 dB calc.

General

Size12″
Voice coilsdual 4 Ω
RMS power400 W

Mounting dimensions

Ø≈ 12 5/16″cutout Ø11 1/8″mounting depth 6″magnet Ø≈ 7 1/4″
Cutout diameter11 1/8″
Mounting depth6″

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 Pioneer 12″ models