18 Sound 8NMB420

8" · 16 Ω · 280 W · 95 dB · datasheet ↗

Thiele-Small parameters

Nominal size	8"
Impedance	16 Ω
Fs	66 Hz
Qts	0.41
Qes	0.47
Qms	3.2
Vas	24.53 L
Sd	227 cm²
Xmax	5.8 mm
Re	9.8 Ω
Bl	12 T·m
Mms	17 g
Pe	280 W
Sensitivity	95 dB

Alignment hint

EBP	140 · ported
Sealed Vb (Qtc ≈ 0.71)	≈ 12.4 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
18 Sound 8MB400	64 -2	0.38 -0.03	23.9 -0.63	5.8 =	95 =	close	8 Ω vs 16 Ω: amp load changes	+
18 Sound 8MB500	74 +8	0.43 +0.02	21.5 -3.03	6 +0.2	95 =	close	8 Ω vs 16 Ω: amp load changes	+
B&C 8MBX51	68 +2	0.38 -0.03	22 -2.53	6 +0.2	97 +2	close	200 W vs 280 W: lower power handling	+
B&C 8FMB51	68 +2	0.39 -0.02	20.5 -4.03	5.5 -0.3	96 +1	close	Xmax 5.5 mm < 5.8 mm: lower excursion-limited SPL	+
18 Sound 8MB500	73 +7	0.5 +0.09	21.3 -3.23	6 +0.2	95 =	usable		+
18 Sound 8MB500	73 +7	0.36 -0.05	18.4 -6.13	6 +0.2	95 =	usable	4 Ω vs 16 Ω: amp load changes	+
Beyma 8"G40	70 +4	0.36 -0.05	17 -7.53	6.5 +0.7	95 =	usable	8 Ω vs 16 Ω: amp load changes	+
Faital PRO 8FE300	70 +4	0.44 +0.03	15.7 -8.83	5.52 -0.28	95 =	usable	8 Ω vs 16 Ω: amp load changes · Xmax 5.52 mm < 5.8 mm: lower excursion-limited SPL	+
LaVoce FBASS08-18	53 -13	0.4 -0.01	23.64 -0.89	4.5 -1.3	92.5 -2.5	usable	8 Ω vs 16 Ω: amp load changes · 150 W vs 280 W: lower power handling · Xmax 4.5 mm < 5.8 mm: lower excursion-limited SPL	+
Eminence BETA-8A	65 -1	0.38 -0.03	23.3 -1.23	3 -2.8	95.1 +0.1	usable	8 Ω vs 16 Ω: amp load changes · Xmax 3 mm < 5.8 mm: lower excursion-limited SPL	+

Compare the closest 3 against the 8NMB420 →

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.