Ciare NDC 21-5

21.5" · 8 Ω · 1500 W · 97.2 dB · datasheet ↗

Thiele-Small parameters

Nominal size	21.5"
Impedance	8 Ω
Fs	32.2 Hz
Qts	0.344
Qes	0.35
Qms	18.93
Vas	270.8 L
Sd	1662 cm²
Xmax	8.8 mm
Re	6.22 Ω
Bl	35.4 T·m
Mms	349.3 g
Pe	1500 W
Sensitivity	97.2 dB

Alignment hint

EBP	92 · flexible
Sealed Vb (Qtc ≈ 0.71)	≈ 84 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
Beyma 21SW1600ND	33 +0.8	0.382 +0.04	268 -2.8	8.9 +0.1	97.6 +0.4	close		+
B&C 21 SW 115 v2015	33 +0.8	0.353 +0.01	278 +7.2	9.3 +0.5	100.6 +3.4	close	4 Ω vs 8 Ω: amp load changes	+
SB Audience NERO-21SW1100D	32 -0.2	0.339 =	312.6 +41.8	8.1 -0.7	98.6 +1.4	close	1100 W vs 1500 W: lower power handling · Xmax 8.1 mm < 8.8 mm: lower excursion-limited SPL	+
18 Sound 21NLW9000	29 -3.2	0.347 =	304 +33.2	10.7 +1.9	96.4 -0.8	close		+
RCF 21LNW9000	29 -3.2	0.347 =	304 +33.2	10.7 +1.9	96.4 -0.8	close		+
B&C 21 SW 115	32.5 +0.3	0.404 +0.06	268.7 -2.1	9.9 +1.1	99.2 +2	close	4 Ω vs 8 Ω: amp load changes	+
Ciare NDK 21-4	28.5 -3.7	0.322 -0.02	232.4 -38.4	8 -0.8	97.4 +0.2	close	4 Ω vs 8 Ω: amp load changes · Xmax 8 mm < 8.8 mm: lower excursion-limited SPL	+
LaVoce SAF214.50 vp	30 -2.2	0.401 +0.06	311 +40.2	11.6 +2.8	96.4 -0.8	usable		+
Eminence NSW6021-6	29 -3.2	0.304 -0.04	224.6 -46.2	10.3 +1.5	97.7 +0.5	usable	4 Ω vs 8 Ω: amp load changes	+
Beyma 21L50	33 +0.8	0.434 +0.09	300 +29.2	7.9 -0.9	97 -0.2	usable	1000 W vs 1500 W: lower power handling · Xmax 7.9 mm < 8.8 mm: lower excursion-limited SPL	+

Compare the closest 3 against the NDC 21-5 →

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.