Sony XS-L121P5

12" · 4 Ω · 350 W · 85.5 dB · datasheet ↗

Thiele-Small parameters

Nominal size	12"
Impedance	4 Ω
Fs	26.4 Hz
Qts	0.42
Qes	0.44
Qms	5.9
Vas	55.5 L
Sd	486 cm²
Xmax	7.5 mm
Re	3.2 Ω
Bl	16.1 T·m
Mms	219 g
Pe	350 W
Sensitivity	85.5 dB

Alignment hint

EBP	60 · flexible
Sealed Vb (Qtc ≈ 0.71)	≈ 30.3 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
Earthquake Sound SUBZERO-12	26.8 +0.4	0.424 =	58.1 +2.6	12.7 +5.2	86.2 +0.7	close	8 Ω vs 4 Ω: amp load changes	+
Infinity KAPPA 120.9W	27.2 +0.8	0.43 +0.01	54.4 -1.1	6.7 -0.8	87.9 +2.4	close	8 Ω vs 4 Ω: amp load changes · Xmax 6.7 mm < 7.5 mm: lower excursion-limited SPL	+
Ground Zero GZRW 12XD-AL	29 +2.6	0.451 +0.03	52 -3.5	9.2 +1.7	86.1 +0.6	close	8 Ω vs 4 Ω: amp load changes	+
Rockford Fosgate T0D212	25.3 -1.1	0.473 +0.05	55 -0.5	10.5 +3	88 +2.5	close		+
Rockford Fosgate T0D412	26 -0.4	0.529 +0.11	55.1 -0.4	10.7 +3.2	85.3 -0.2	close	8 Ω vs 4 Ω: amp load changes	+
Audiomobile ELITE 2212	28 +1.6	0.48 +0.06	59.46 +3.96	12.7 +5.2	85.8 +0.3	close		+
OmnesAudio SW12HEX	26.4 =	0.453 +0.03	68.7 +13.2	7 -0.5	86.9 +1.4	close	8 Ω vs 4 Ω: amp load changes · 250 W vs 350 W: lower power handling · Xmax 7 mm < 7.5 mm: lower excursion-limited SPL	+
Pioneer TS-W126C(PREMIER)	32.6 +6.2	0.42 =	55.614 +0.11	8.7 +1.2	88.4 +2.9	close		+
Max Speaker MF300/77S4	26.4 =	0.383 -0.04	53.1 -2.4	6.7 -0.8	89 +3.5	close	Xmax 6.7 mm < 7.5 mm: lower excursion-limited SPL	+
Alpine SWR-12D2 vp	27 +0.6	0.441 +0.02	46 -9.5	10 +2.5	87.8 +2.3	close	8 Ω vs 4 Ω: amp load changes	+

Compare the closest 3 against the XS-L121P5 →

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.