Audax HD33S66

12" · 8 Ω · 150 W · 98 dB

Thiele-Small parameters

Nominal size	12"
Impedance	8 Ω
Fs	24 Hz
Qts	0.145
Qes	0.16
Qms	1.59
Vas	338 L
Sd	530 cm²
Xmax	3.5 mm
Re	5.8 Ω
Bl	16.7 T·m
Mms	51.2 g
Pe	150 W
Sensitivity	98 dB

Alignment hint

EBP	150 · ported
Sealed Vb (Qtc ≈ 0.71)	≈ 14.8 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
Fertin Acoustics 30SM8	21.7 -2.3	0.146 =	324 -14	3 -0.5	96.5 -1.5	close	50 W vs 150 W: lower power handling · Xmax 3 mm < 3.5 mm: lower excursion-limited SPL	+
Fertin Acoustics 30EXM8	23.7 -0.3	0.147 =	250 -88	3 -0.5	96.5 -1.5	usable	50 W vs 150 W: lower power handling · Xmax 3 mm < 3.5 mm: lower excursion-limited SPL	+
Focal AUDIOM 12A	21.5 -2.5	0.165 +0.02	489 +151	4.5 +1	97.8 -0.2	usable		+
Monacor SPH-300TC v1	23 -1	0.198 +0.05	315 -23	4 +0.5	95.4 -2.6	usable		+
Focal AUDIOM 12V	25 +1	0.203 +0.06	318 -20	6 +2.5	97 -1	usable		+
Pioneer A30GU30-55D	24 =	0.209 +0.06	277 -61	3.1 -0.4	97.9 -0.1	usable	4 Ω vs 8 Ω: amp load changes · Xmax 3.1 mm < 3.5 mm: lower excursion-limited SPL	+
Fertin Acoustics 30 MODEL 7	22 -2	0.098 -0.05	336 -2	3 -0.5	98.6 +0.6	usable	40 W vs 150 W: lower power handling · Xmax 3 mm < 3.5 mm: lower excursion-limited SPL	+
Tannoy 3128	25 +1	0.195 +0.05	276 -62	3 -0.5	96.5 -1.5	usable	80 W vs 150 W: lower power handling · Xmax 3 mm < 3.5 mm: lower excursion-limited SPL	+
Tannoy HPD 315A	25 +1	0.195 +0.05	276 -62	3 -0.5	96.5 -1.5	usable	60 W vs 150 W: lower power handling · Xmax 3 mm < 3.5 mm: lower excursion-limited SPL	+
Audax LFP502	24 =	0.208 +0.06	267 -71	3.5 =	95.4 -2.6	usable		+

Compare the closest 3 against the HD33S66 →

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.