EMS B12

12" · 8 Ω · 100 W · 98.8 dB · datasheet ↗

Thiele-Small parameters

Nominal size	12"
Impedance	8 Ω
Fs	31 Hz
Qts	0.168
Qes	0.173
Qms	5.657
Vas	227 L
Sd	515 cm²
Xmax	4.4 mm
Re	6.57 Ω
Bl	17.9 T·m
Mms	43.2 g
Pe	100 W
Sensitivity	98.8 dB

Alignment hint

EBP	179 · ported
Sealed Vb (Qtc ≈ 0.71)	≈ 13.6 L

EBP > 100: favours a ported (bass-reflex) 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
EMS B12 MKII	30 -1	0.174 +0.01	227 =	4.6 +0.2	98.3 -0.5	close		+
Audax PR33S66	30 -1	0.169 =	214.4 -12.6	3.8 -0.6	98.2 -0.6	close	Xmax 3.8 mm < 4.4 mm: lower excursion-limited SPL	+
Fluxmag 1201-LB	28.9 -2.1	0.163 -0.01	196.2 -30.8	4 -0.4	98.4 -0.4	close	Xmax 4 mm < 4.4 mm: lower excursion-limited SPL	+
Altec 414-8E	30.3 -0.7	0.195 +0.03	224 -3	4 -0.4	97.9 -0.9	close	Xmax 4 mm < 4.4 mm: lower excursion-limited SPL	+
Altec 414-8C	30.2 -0.8	0.204 +0.04	230.2 +3.2	4 -0.4	97.5 -1.3	close	Xmax 4 mm < 4.4 mm: lower excursion-limited SPL	+
Altec 414 Z	32 +1	0.219 +0.05	263 +36	4 -0.4	96.2 -2.6	usable	16 Ω vs 8 Ω: amp load changes · Xmax 4 mm < 4.4 mm: lower excursion-limited SPL	+
Audax PR330M0 v2014	26 -5	0.203 +0.04	208 -19	4 -0.4	95.6 -3.2	usable	Xmax 4 mm < 4.4 mm: lower excursion-limited SPL	+
Monacor SP-330PAX	33 +2	0.238 +0.07	190 -37	4.5 +0.1	97.4 -1.4	usable		+
RCF L 12P24	31 =	0.145 -0.02	205 -22	2 -2.4	99 +0.2	usable	75 W vs 100 W: lower power handling · Xmax 2 mm < 4.4 mm: lower excursion-limited SPL	+
Beyma 12XA30/ND	35 +4	0.21 +0.04	172 -55	4 -0.4	97.2 -1.6	usable	Xmax 4 mm < 4.4 mm: lower excursion-limited SPL	+

Compare the closest 3 against the B12 →

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.