B&C 18DS115

18" · 8 Ω · 1700 W · 98 dB · datasheet ↗

Thiele-Small parameters

Nominal size	18"
Impedance	8 Ω
Fs	30 Hz
Qts	0.2
Qes	0.21
Qms	4.3
Vas	168 L
Sd	1210 cm²
Xmax	16.5 mm
Re	5 Ω
Bl	39 T·m
Mms	330 g
Pe	1700 W
Sensitivity	98 dB

Alignment hint

EBP	143 · ported
Sealed Vb (Qtc ≈ 0.71)	≈ 14.6 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
B&C 18DS115	30 =	0.17 -0.03	177 +9	16.5 =	97 -1	close	4 Ω vs 8 Ω: amp load changes	+
Precision Devices PD1850	30 =	0.21 +0.01	249 +81	16 -0.5	98 =	close	800 W vs 1700 W: lower power handling · Xmax 16 mm < 16.5 mm: lower excursion-limited SPL	+
B&C 18DS100	32 +2	0.24 +0.04	157 -11	14 -2.5	98 =	usable	4 Ω vs 8 Ω: amp load changes · Xmax 14 mm < 16.5 mm: lower excursion-limited SPL	+
Beyma 18QLEX1600Fe	30 =	0.23 +0.03	195 +27	13 -3.5	97 -1	usable	Xmax 13 mm < 16.5 mm: lower excursion-limited SPL	+
B&C 18 DS 115	30 =	0.2 =	168 =	7.5 -9	97.4 -0.6	usable	Xmax 7.5 mm < 16.5 mm: lower excursion-limited SPL	+
B&C 18RS115	33 +3	0.22 +0.02	125 -43	23.5 +7	97.4 -0.6	usable		+
18 Sound 18iD200	29 -1	0.17 -0.03	136 -32	18 +1.5	95 -3	usable	2 Ω vs 8 Ω: amp load changes	+
18 Sound 18iDSDS	29 -1	0.17 -0.03	136 -32	18 +1.5	95 -3	usable	2 Ω vs 8 Ω: amp load changes	+
18 Sound 18NLW9000	32 +2	0.21 +0.01	247 +79	14 -2.5	97 -1	usable	4 Ω vs 8 Ω: amp load changes · Xmax 14 mm < 16.5 mm: lower excursion-limited SPL	+
Beyma 18QLEX1600Fe	31 +1	0.25 +0.05	177.2 +9.2	13 -3.5	96 -2	usable	4 Ω vs 8 Ω: amp load changes · Xmax 13 mm < 16.5 mm: lower excursion-limited SPL	+

Compare the closest 3 against the 18DS115 →

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 (3)

18" Bass Reflexsubbass reflex
18" Kickbin Bandpasskickbandpass
18" Tapped Hornsubtapped horn