Rockford Fosgate R2SD4-12

12" · 8 Ω · 250 W · 86.7 dB · datasheet ↗

Thiele-Small parameters

Nominal size	12"
Impedance	8 Ω
Fs	30.3 Hz
Qts	0.653
Qes	0.72
Qms	7
Vas	65.4 L
Sd	534.8 cm²
Xmax	6.9 mm
Re	6.8 Ω
Bl	17.4 T·m
Mms	169.1 g
Pe	250 W
Sensitivity	86.7 dB

Alignment hint

EBP	42 · sealed
Sealed Vb (Qtc ≈ 0.71)	≈ 378.9 L

EBP < 50: favours a sealed (closed) 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
Cerwin-Vega VEGA 124	30.3 =	0.612 -0.04	60.3 -5.1	7 +0.1	86.4 -0.3	close		+
Wavecor SW310WA01	28.5 -1.8	0.603 -0.05	65.5 +0.1	7.6 +0.7	86.8 +0.1	close		+
Alpine SWE-1242	31 +0.7	0.66 +0.01	61 -4.4	11.7 +4.8	85.9 -0.8	close	4 Ω vs 8 Ω: amp load changes	+
Wavecor SW312WA04	29 -1.3	0.569 -0.08	61 -4.4	7.5 +0.6	86.8 +0.1	close		+
JL Audio 12W0V3-4	32.09 +1.79	0.67 +0.02	71.64 +6.24	11.4 +4.5	85.64 -1.06	close	4 Ω vs 8 Ω: amp load changes	+
Alpine SWE-1241	31 +0.7	0.653 =	61 -4.4	11.3 +4.4	89.6 +2.9	close	4 Ω vs 8 Ω: amp load changes	+
JL Audio 12W0V3-4	28.4 -1.9	0.67 +0.02	71.6 +6.2	9.3 +2.4	88.3 +1.6	close		+
Pioneer TS-W251R	28.9 -1.4	0.68 +0.03	57.86 -7.54	7.8 +0.9	84.6 -2.1	close	4 Ω vs 8 Ω: amp load changes · 120 W vs 250 W: lower power handling	+
Soundstream STEALTH-124	29.98 -0.32	0.687 +0.03	59.5 -5.9	13 +6.1	84.8 -1.9	close		+
MTX Audio T5512-04	29.3 -1	0.583 -0.07	66.9 +1.5	7.3 +0.4	89.8 +3.1	close	4 Ω vs 8 Ω: amp load changes	+

Compare the closest 3 against the R2SD4-12 →

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.