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Focal 33 K

13" · 4 Ω · 400 W · 90.1 dB · datasheet ↗

Thiele-Small parameters

Nominal size13"
Impedance4 Ω
Fs38.4 Hz
Qts0.41
Qes0.44
Qms7.2
Vas51.8 L
Sd549 cm²
Xmax9 mm
Re3.7 Ω
Bl17 T·m
Mms141.5 g
Pe400 W
Sensitivity90.1 dB

Alignment hint

EBP87 · flexible
Sealed Vb (Qtc ≈ 0.71)≈ 26.2 L

EBP 50-100: works in either a sealed or ported alignment.

Rules of thumb from T/S parameters only. Verify against a real simulation before cutting wood.

Substitute candidates

DriverFs (Hz)QtsVas (L)Xmax (mm)Sens (dB)FitNotesCompare
Soundstream STEALTH-1330.2 -8.20.85 +0.4442.17 -9.636 -380.7 -9.4risky200 W vs 400 W: lower power handling · Xmax 6 mm < 9 mm: lower excursion-limited SPL+
HiVi D5.852 +13.60.37 -0.045.6 -46.24.8 -4.284.6 -5.5risky8 Ω vs 4 Ω: amp load changes · 60 W vs 400 W: lower power handling · Xmax 4.8 mm < 9 mm: lower excursion-limited SPL+

Compare the closest 2 against the 33 K →

Ranked on parameter similarity only (Qts, Fs, Vas, Xmax, sensitivity). Same nominal size required. A hint, not a simulation, model the swap before cutting or buying.

Used in enclosures (0)

No enclosure in the catalog uses this driver yet.