Focal R-250S

10" · 4 Ω · 250 W · 88.2 dB · datasheet ↗

Thiele-Small parameters

Nominal size	10"
Impedance	4 Ω
Fs	35.4 Hz
Qts	0.596
Qes	0.659
Qms	6.213
Vas	28.1 L
Sd	314 cm²
Xmax	7 mm
Re	3.58 Ω
Bl	11 T·m
Mms	99.4 g
Pe	250 W
Sensitivity	88.2 dB

Alignment hint

EBP	54 · flexible
Sealed Vb (Qtc ≈ 0.71)	≈ 68.9 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

Driver	Fs (Hz)	Qts	Vas (L)	Xmax (mm)	Sens (dB)	Fit	Notes	Compare
hertz Hertz Audio ES 250.5	35 -0.4	0.609 +0.01	27.7 -0.4	6.6 -0.4	89 +0.8	close	Xmax 6.6 mm < 7 mm: lower excursion-limited SPL	+
MTX Audio 5510-44	33.6 -1.8	0.63 +0.03	29.2 +1.1	7.2 +0.2	90.1 +1.9	close	2 Ω vs 4 Ω: amp load changes	+
Polk Audio DB1040	35 -0.4	0.55 -0.05	28.3 +0.2	7.5 +0.5	85 -3.2	close		+
hertz Hertz Audio ML2500.3	33 -2.4	0.598 =	23.5 -4.6	10.3 +3.3	87.8 -0.4	close		+
JL Audio 10W0V3-4	32.1 -3.3	0.604 +0.01	31 +2.9	8.7 +1.7	86.7 -1.5	close	8 Ω vs 4 Ω: amp load changes	+
Hertz Audio DS 250.3	36 +0.6	0.62 +0.02	29 +0.9	10 +3	84.8 -3.4	close		+
Sony XS-GTR100L	40 +4.6	0.56 -0.04	27 -1.1	7.5 +0.5	86.2 -2	close		+
Wavecor SW275BD01	30.8 -4.6	0.564 -0.03	31 +2.9	6.9 -0.1	87.2 -1	close	180 W vs 250 W: lower power handling · Xmax 6.9 mm < 7 mm: lower excursion-limited SPL	+
Focal SUB10WM	31 -4.4	0.683 +0.09	28 -0.1	8.5 +1.5	86.5 -1.7	close		+
Morel PRIMO 10	35 -0.4	0.558 -0.04	38 +9.9	8 +1	90 +1.8	usable		+

Compare the closest 3 against the R-250S →

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.