Focal Access 30 A4 (SVC 4 ohm)

12″ subwoofer · 4 Ω · 250 W RMS

Fs 24.7 HzQts 0.67Vas 3.07 ft³Xmax 0.33″

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 volume1.80 ft³ (51 L)
Qtc1.10
Fc41 Hz
F3 (−3 dB, no cabin gain)32 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 9 1/16″
Open sealed box in designer

Ported

Net volume3.07 ft³ (87 L)
Tuning (Fb)31 Hz
Portslot 1 9/16 × 14 5/16″, 16 1/2″ long
Port velocity at 250 W54 ft/s
F3 (−3 dB, no cabin gain)27 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 15 5/16″
Open ported box in designer
203040506080100150200667278849096HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs24.7 Hz
Qts0.67
Qes0.764
Qms5.49
Vas3.07 ft³
Re4.01 Ω
Sd79.2 in²
Xmax0.33″
Vd26.5 in³ calc.
Mms176 g calc.
BL12 T·m calc.
EBP32 — suits sealed calc.
Sensitivity, 1 W / 1 m84.3 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 Focal 12″ models