Alpine 1242D

12" · 4 Ω · 1000 W · 91.4 dB · datasheet ↗

Thiele-Small parameters

Nominal size	12"
Impedance	4 Ω
Fs	29 Hz
Qts	0.47
Qes	0.5
Qms	7.89
Vas	45 L
Sd	480 cm²
Xmax	9.1 mm
Re	2 Ω
Bl	12.6 T·m
Mms	216.2 g
Pe	1000 W
Sensitivity	91.4 dB

Alignment hint

EBP	58 · flexible
Sealed Vb (Qtc ≈ 0.71)	≈ 35.6 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
JBL P1220	28.7 -0.3	0.448 -0.02	47.4 +2.4	7.8 -1.3	91.8 +0.4	close	2 Ω vs 4 Ω: amp load changes · 400 W vs 1000 W: lower power handling · Xmax 7.8 mm < 9.1 mm: lower excursion-limited SPL	+
JBL W12GTI	31.8 +2.8	0.508 +0.04	44.8 -0.2	9.9 +0.8	90.1 -1.3	close	700 W vs 1000 W: lower power handling	+
JBL W12GTi MKII	31.8 +2.8	0.508 +0.04	44.8 -0.2	9.9 +0.8	90.1 -1.3	close	700 W vs 1000 W: lower power handling	+
JBL W12GTIe	31.8 +2.8	0.508 +0.04	44.8 -0.2	9.9 +0.8	90.1 -1.3	close	700 W vs 1000 W: lower power handling	+
Alpine SWR-1242D 12	29 =	0.47 =	45 =	9.1 =	85.7 -5.7	close	8 Ω vs 4 Ω: amp load changes	+
Alpine SWR-12D2 vp	27 -2	0.441 -0.03	46 +1	10 +0.9	87.8 -3.6	close	8 Ω vs 4 Ω: amp load changes · 750 W vs 1000 W: lower power handling	+
Powerbass L-124D 12	29 =	0.489 +0.02	59 +14	9 -0.1	93.2 +1.8	close	2 Ω vs 4 Ω: amp load changes · 400 W vs 1000 W: lower power handling · Xmax 9 mm < 9.1 mm: lower excursion-limited SPL	+
MTX Audio TX612	27 -2	0.393 -0.08	42.7 -2.3	9.7 +0.6	91 -0.4	close		+
Focal E30KX	29 =	0.454 -0.02	50 +5	10.7 +1.6	86.9 -4.5	close	8 Ω vs 4 Ω: amp load changes	+
Focal SUB30KXE	29 =	0.454 -0.02	50 +5	10.8 +1.7	86.9 -4.5	close	8 Ω vs 4 Ω: amp load changes	+

Compare the closest 3 against the 1242D →

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.