Rockford Fosgate S2-124

12" · 4 Ω · 500 W · 89.9 dB · datasheet ↗

Thiele-Small parameters

Nominal size	12"
Impedance	4 Ω
Fs	27 Hz
Qts	0.498
Qes	0.53
Qms	8.12
Vas	77 L
Sd	540 cm²
Xmax	10.7 mm
Re	3.7 Ω
Bl	14.8 T·m
Mms	184.5 g
Pe	500 W
Sensitivity	89.9 dB

Alignment hint

EBP	51 · flexible
Sealed Vb (Qtc ≈ 0.71)	≈ 75.8 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
JL Audio 12W3V3-4	26.7 -0.3	0.446 -0.05	80.6 +3.6	10.9 +0.2	90.6 +0.7	close		+
JL Audio 12W1V3-4	26.21 -0.79	0.5 =	76.63 -0.37	11 +0.3	86.1 -3.8	close	300 W vs 500 W: lower power handling	+
Dayton Audio RSS315HF-4	25 -2	0.489 -0.01	85.1 +8.1	10.1 -0.6	89.4 -0.5	close	Xmax 10.1 mm < 10.7 mm: lower excursion-limited SPL	+
Infinity PRIMUS 1270	29.7 +2.7	0.49 -0.01	75.7 -1.3	11.3 +0.6	87.3 -2.6	close	300 W vs 500 W: lower power handling	+
JL Audio 12W7AE-3	27.2 +0.2	0.482 -0.02	66 -11	13.7 +3	91.2 +1.3	close		+
Focal P30F	28 +1	0.467 -0.03	70 -7	9.1 -1.6	90.1 +0.2	close	Xmax 9.1 mm < 10.7 mm: lower excursion-limited SPL	+
Aura Sound NS12-794-4A	27 =	0.423 -0.08	78 +1	9.9 -0.8	90.9 +1	close	Xmax 9.9 mm < 10.7 mm: lower excursion-limited SPL	+
JL Audio 12W1V3-2	26.55 -0.45	0.52 +0.02	72 -5	11 +0.3	85.9 -4	close	2 Ω vs 4 Ω: amp load changes · 300 W vs 500 W: lower power handling	+
Audio System HX12 SQ	28.2 +1.2	0.5 =	68 -9	11.8 +1.1	86.1 -3.8	close		+
Morel ULTIMO 124	26 -1	0.421 -0.08	73.8 -3.2	14.6 +3.9	89 -0.9	close		+

Compare the closest 3 against the S2-124 →

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.