Hertz Audio DS 30.3

12" · 4 Ω · 250 W · 87.7 dB · datasheet ↗

Thiele-Small parameters

Nominal size	12"
Impedance	4 Ω
Fs	29 Hz
Qts	0.51
Qes	0.59
Qms	3.95
Vas	94 L
Sd	529 cm²
Xmax	9 mm
Re	3.43 Ω
Bl	11.6 T·m
Mms	127 g
Pe	250 W
Sensitivity	87.7 dB

Alignment hint

EBP	49 · sealed
Sealed Vb (Qtc ≈ 0.71)	≈ 101.9 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
American Bass SL 124	31.5 +2.5	0.543 +0.03	85.7 -8.3	8.5 -0.5	88.3 +0.6	close	Xmax 8.5 mm < 9 mm: lower excursion-limited SPL	+
Infinity PRIMUS 1270	29.7 +0.7	0.49 -0.02	75.7 -18.3	11.3 +2.3	87.3 -0.4	close		+
Focal AUDITOR RSB-300	25 -4	0.466 -0.04	93 -1	10.2 +1.2	87.4 -0.3	close	8 Ω vs 4 Ω: amp load changes	+
Morel PRIMO 124	28 -1	0.47 -0.04	85 -9	8 -1	87.1 -0.6	close	Xmax 8 mm < 9 mm: lower excursion-limited SPL	+
Alpine SWE-1244E	31 +2	0.53 +0.02	102.5 +8.5	7.5 -1.5	88.7 +1	close	Xmax 7.5 mm < 9 mm: lower excursion-limited SPL	+
JL Audio 12WX-4	27 -2	0.562 +0.05	94.5 +0.5	8.5 -0.5	90.5 +2.8	close	Xmax 8.5 mm < 9 mm: lower excursion-limited SPL	+
Dayton Audio RSS315HF-4	25 -4	0.489 -0.02	85.1 -8.9	10.1 +1.1	89.4 +1.7	close		+
JL Audio 12W1V2-8	24.98 -4.02	0.458 -0.05	100.15 +6.15	9.5 +0.5	86.8 -0.9	close	8 Ω vs 4 Ω: amp load changes	+
Alpine SWA-12S4	30 +1	0.49 -0.02	67.79 -26.21	10 +1	87.2 -0.5	close		+
Sound Storm Labs CR12D	30.7 +1.7	0.522 +0.01	66.9 -27.1	10.3 +1.3	87.5 -0.2	close	8 Ω vs 4 Ω: amp load changes	+

Compare the closest 3 against the DS 30.3 →

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.