PHL Audio 6121M-20

15" · 8 Ω · 800 W · 98.5 dB · datasheet ↗

Thiele-Small parameters

Nominal size	15"
Impedance	8 Ω
Fs	39 Hz
Qts	0.235
Qes	0.25
Qms	4
Vas	119 L
Sd	892 cm²
Xmax	5.6 mm
Re	5 Ω
Bl	27.7 T·m
Mms	156.1 g
Pe	800 W
Sensitivity	98.5 dB

Alignment hint

EBP	156 · ported
Sealed Vb (Qtc ≈ 0.71)	≈ 14.8 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
PHL Audio 6031	41 +2	0.236 =	117 -2	6.3 +0.7	98.6 +0.1	close		+
Oberton 15PD601	38.2 -0.8	0.228 -0.01	133.31 +14.31	8.5 +2.9	98 -0.5	close	600 W vs 800 W: lower power handling	+
18 Sound 15NLW9401	40 +1	0.25 +0.02	114 -5	10 +4.4	97.5 -1	close	4 Ω vs 8 Ω: amp load changes	+
18 Sound 15LW1401	39 =	0.26 +0.03	127 +8	9 +3.4	98 -0.5	close	4 Ω vs 8 Ω: amp load changes	+
Oberton 15NB500	42.77 +3.77	0.255 +0.02	121.46 +2.46	7.25 +1.65	99 +0.5	close	500 W vs 800 W: lower power handling	+
18 Sound 15LW1401 4 Ohms	39 =	0.26 +0.03	127 +8	7.4 +1.8	100 +1.5	close	4 Ω vs 8 Ω: amp load changes	+
18 Sound 15LW1400	42 +3	0.245 +0.01	137 +18	6.7 +1.1	99.3 +0.8	close		+
PHL Audio 6030	38 -1	0.264 +0.03	130 +11	7.2 +1.6	97.6 -0.9	close		+
B&C 15CL76	42 +3	0.25 +0.02	140 +21	7 +1.4	98 -0.5	close	4 Ω vs 8 Ω: amp load changes · 400 W vs 800 W: lower power handling	+
Faital PRO 15HP1020	40 +1	0.27 +0.04	126.6 +7.6	9 +3.4	98 -0.5	close		+

Compare the closest 3 against the 6121M-20 →

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.