RCF LF 18X400

18" · 8 Ω · 1000 W · 98.6 dB · datasheet ↗

Thiele-Small parameters

Nominal size	18"
Impedance	8 Ω
Fs	28 Hz
Qts	0.255
Qes	0.27
Qms	4.5
Vas	360 L
Sd	1231.1 cm²
Xmax	9 mm
Re	5.1 Ω
Bl	25.2 T·m
Mms	190.7 g
Pe	1000 W
Sensitivity	98.6 dB

Alignment hint

EBP	104 · ported
Sealed Vb (Qtc ≈ 0.71)	≈ 53.8 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
RCF LF 18G400	28 =	0.273 +0.02	360 =	9 =	98.3 -0.3	close		+
RCF LF18G400	28 =	0.27 +0.02	360 =	9 =	97.5 -1.1	close		+
RCF LF18X400	28 =	0.27 +0.02	340 -20	9 =	97.5 -1.1	close		+
RCF LF 18X400 v2	28 =	0.278 +0.02	340 -20	9 =	98 -0.6	close		+
Faital PRO 18FH510	30 +2	0.26 +0.01	391.4 +31.4	9.45 +0.45	98 -0.6	close	4 Ω vs 8 Ω: amp load changes · 600 W vs 1000 W: lower power handling	+
RCF L 18P400	29 +1	0.279 +0.02	340 -20	8.8 -0.2	98.5 -0.1	close	Xmax 8.8 mm < 9 mm: lower excursion-limited SPL	+
PD PD 182	28 =	0.238 -0.02	391 +31	8.2 -0.8	98.7 +0.1	close	600 W vs 1000 W: lower power handling · Xmax 8.2 mm < 9 mm: lower excursion-limited SPL	+
Precision Devices PD 182	28 =	0.238 -0.02	391 +31	8.2 -0.8	98.7 +0.1	close	600 W vs 1000 W: lower power handling · Xmax 8.2 mm < 9 mm: lower excursion-limited SPL	+
B&C 18 PZB 46 vp	28.8 +0.8	0.227 -0.03	346.4 -13.6	8.1 -0.9	99 +0.4	close	700 W vs 1000 W: lower power handling · Xmax 8.1 mm < 9 mm: lower excursion-limited SPL	+
18 Sound 18ND9300	30 +2	0.28 +0.03	322 -38	9.5 +0.5	98.8 +0.2	close		+

Compare the closest 3 against the LF 18X400 →

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.