Blaupunkt TWB 1500 (SVC 4 ohm)

12″ subwoofer · 4 Ω · 250 W RMS

Fs 29.8 HzQts 0.56Vas 3.29 ft³Xmax 0.31″
The published specs don’t add up:

Recommended box

For a sedan, one sub, 250 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)
Qtc0.96
Fc51 Hz
F3 (−3 dB, no cabin gain)43 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)36 Hz
Portslot 1 9/16 × 14 5/16″, 11 15/16″ long
Port velocity at 250 W58 ft/s
F3 (−3 dB, no cabin gain)33 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 14 7/16″
Open ported box in designer
203040506080100150200667278849096HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs29.8 Hz
Qts0.56
Qes0.61
Qms7.08
Vas3.29 ft³
Re≈ 3.4 Ω
Sd≈ 76 in²
Xmax0.31″
EBP49 — suits sealed calc.
Sensitivity, 1 W / 1 m88.1 dB calc.

General

Size12″
Voice coils4 Ω
RMS power250 W

Mounting dimensions

Ø≈ 12 5/16″cutout ≈ Ø11 1/8″mounting depth ≈ 5 7/8″magnet Ø≈ 7 3/16″
Cutout diameter≈ 11 1/8″
Mounting depth≈ 5 7/8″

“≈” 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.

Data sources

Other Blaupunkt 12″ models