Beyma 21L45

21.5" · 8 Ω · 800 W · 98.7 dB · datasheet ↗

Thiele-Small parameters

Nominal size	21.5"
Impedance	8 Ω
Fs	25 Hz
Qts	0.275
Qes	0.28
Qms	14.16
Vas	660 L
Sd	1764 cm²
Xmax	9 mm
Re	6.3 Ω
Bl	30.8 T·m
Mms	267.9 g
Pe	800 W
Sensitivity	98.7 dB

Alignment hint

EBP	89 · flexible
Sealed Vb (Qtc ≈ 0.71)	≈ 117.6 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
Pyle Audio PDW21250	22.4 -2.6	0.331 +0.06	703.8 +43.8	9 =	96.2 -2.5	usable		+
hertz Hertz Audio ML5400D	20.7 -4.3	0.303 +0.03	613 -47	8.5 -0.5	102.9 +4.2	usable	2 Ω vs 8 Ω: amp load changes · Xmax 8.5 mm < 9 mm: lower excursion-limited SPL	+
Beyma 21LEX1600/Nd	30 +5	0.272 =	394 -266	9.3 +0.3	99.3 +0.6	usable		+
MCM Electronics 55-2985	25.9 +0.9	0.38 +0.1	705 +45	6.9 -2.1	97.6 -1.1	usable	300 W vs 800 W: lower power handling · Xmax 6.9 mm < 9 mm: lower excursion-limited SPL	+
RCF LF 21N451	30 +5	0.239 -0.04	440 -220	8.9 -0.1	100.4 +1.7	usable	Xmax 8.9 mm < 9 mm: lower excursion-limited SPL	+
RCF LF 21N451 v2017	30 +5	0.259 -0.02	375 -285	8.6 -0.4	99.3 +0.6	usable	Xmax 8.6 mm < 9 mm: lower excursion-limited SPL	+
18 Sound 21LW400	28 +3	0.234 -0.04	385 -275	9.3 +0.3	99.5 +0.8	usable		+
PD PD 2150	22 -3	0.193 -0.08	628 -32	6 -3	98.9 +0.2	usable	400 W vs 800 W: lower power handling · Xmax 6 mm < 9 mm: lower excursion-limited SPL	+
Precision Devices PD 2150	22 -3	0.193 -0.08	628 -32	6 -3	98.9 +0.2	usable	400 W vs 800 W: lower power handling · Xmax 6 mm < 9 mm: lower excursion-limited SPL	+
Beyma 21PW1400FE	30 +5	0.343 +0.07	401.5 -258.5	10 +1	98.6 -0.1	usable		+

Compare the closest 3 against the 21L45 →

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.