SPL Dynamics subwoofers

Thiele/Small parameters of SPL Dynamics subwoofers (10″–18″) and a recommended sealed and ported box for every model, in a free sub box calculator.

Size

Voice coils

Ω per coil

Qts

43 models

Model	Size	Voice coils	Fs, Hz	Qts	Vas, ft³	Xmax, in	RMS, W	Box, ft³ · Hz
10″ 13 models
PRO-10D2 MK3	10″	dual 2 Ω	34	0.47	1.20	0.59	400	Sealed 0.60 Ported 0.95 · 45
PRO-10D2 MK4	10″	dual 2 Ω	46	0.55	0.49	0.67	500	Sealed 0.49 Ported 0.85 · 38
PRO-10D4 MK3	10″	dual 4 Ω	34	0.47	1.20	0.59	400	Sealed 0.60 Ported 0.95 · 45
PRO-10D4 MK4	10″	dual 4 Ω	34	0.47	1.20	0.59	400	Sealed 0.60 Ported 0.95 · 45
PRO-250D2	10″	dual 2 Ω	47	0.62	0.37	0.51	500	Sealed 0.57 Ported 0.85 · 38
SW-250D2	10″	dual 2 Ω	43	0.59	0.37	0.51	350	Sealed 0.51 Ported 0.78 · 38
V-10S	10″	4 Ω	35	0.35	1.94	0.28	200	Sealed 0.49 Ported 1.62 · 37
V-10S4	10″	4 Ω	27	0.37	2.22	0.28	200	Sealed 0.60 Ported 1.70 · 30
V-250D2	10″	dual 2 Ω	32.1	0.46	1.13	0.39	300	Sealed 0.57 Ported 0.92 · 43
V-250D4	10″	dual 4 Ω	32.4	0.50	1.14	0.39	300	Sealed 0.74 Ported 0.92 · 36
V-250S4	10″	4 Ω	32.6	0.47	1.20	0.33	300	Sealed 0.64 Ported 0.95 · 36
XTR-250D2	10″	dual 2 Ω	33.5	0.32	0.65	0.39	750	Sealed 0.46 Ported 1.48 · 37
XTR-250D4	10″	dual 4 Ω	32.7	0.35	0.82	0.43	750	Sealed 0.46 Ported 1.52 · 36
12″ 18 models
PRO-12D2 MK3	12″	dual 2 Ω	29	0.41	1.91	0.67	500	Sealed 0.71 Ported 1.52 · 32
PRO-12D2 MK4	12″	dual 2 Ω	39	0.51	1.37	0.67	500	Sealed 0.92 Ported 1.34 · 34
PRO-12D4 MK3	12″	dual 4 Ω	29	0.41	1.91	0.67	500	Sealed 0.71 Ported 1.52 · 32
PRO-12D4 MK4	12″	dual 4 Ω	39	0.51	1.37	0.67	500	Sealed 0.92 Ported 1.20 · 34
PRO-300D2	12″	dual 2 Ω	32	0.46	1.45	0.51	600	Sealed 0.71 Ported 1.20 · 34
PRO-300D4	12″	dual 4 Ω	34	0.52	1.41	0.51	600	Sealed 1.02 Ported 1.20 · 34
SPL-300D1A	12″	dual 1 Ω	35.1	0.35	0.65	0.45	1,500	Sealed 0.81 Ported 2.61 · 34
SPL-300D2	12″	dual 2 Ω	33.4	0.35	0.82	0.45	1,500	Sealed 0.81 Ported 2.37 · 34
SW-300D2	12″	dual 2 Ω	35.5	0.64	0.98	0.51	450	Sealed 1.73 Ported 1.27 · 34
SW-300D4	12″	dual 4 Ω	35	0.64	0.97	0.51	450	Sealed 1.73 Ported 1.24 · 34
V-12S	12″	4 Ω	28	0.34	4.84	0.28	300	Sealed 1.02 Ported 2.37 · 31
V-12S4	12″	4 Ω	23	0.31	4.80	0.28	300	Sealed 0.81 Ported 2.44 · 30
V-300D2	12″	dual 2 Ω	30.8	0.51	2.38	0.39	350	Sealed 1.59 Ported 1.91 · 34
V-300D4	12″	dual 4 Ω	30.7	0.55	2.31	0.39	350	Sealed 1.77 Ported 1.84 · 34
V-300S4	12″	4 Ω	30	0.47	2.52	0.39	350	Sealed 1.31 Ported 2.01 · 33
XTR-300D2	12″	dual 2 Ω	31.4	0.39	1.48	0.43	750	Sealed 0.74 Ported 2.40 · 34
XTR-300D2S	12″	dual 2 Ω	32.2	0.35	1.36	0.43	1,000	Sealed 0.74 Ported 2.44 · 34
XTR-300D4	12″	dual 4 Ω	31.1	0.39	1.72	0.47	750	Sealed 0.74 Ported 2.44 · 34
15″ 10 models
PRO-15D2 MK3	15″	dual 2 Ω	33	0.42	2.93	0.67	700	Sealed 1.13 Ported 2.33 · 34
PRO-15D2 MK4	15″	dual 2 Ω	37.5	0.42	2.39	0.67	700	Sealed 1.20 Ported 2.12 · 34
PRO-15D4 MK3	15″	dual 4 Ω	33	0.42	2.93	0.67	700	Sealed 1.13 Ported 2.33 · 34
PRO-15D4 MK4	15″	dual 4 Ω	37.5	0.42	2.39	0.67	700	Sealed 1.13 Ported 1.98 · 34
PRO-380D2	15″	dual 2 Ω	31	0.41	2.58	0.51	750	Sealed 1.13 Ported 2.05 · 34
PRO-380D4	15″	dual 4 Ω	31	0.41	2.58	0.51	750	Sealed 1.13 Ported 2.05 · 34
SPL-380D1A	15″	dual 1 Ω	32.4	0.35	1.70	0.45	1,500	Sealed 1.31 Ported 4.20 · 34
SPL-380D2	15″	dual 2 Ω	33.4	0.38	1.46	0.45	1,500	Sealed 1.22 Ported 3.67 · 34
XTR-380D2S	15″	dual 2 Ω	32.5	0.47	2.14	0.51	1,000	Sealed 1.13 Ported 1.98 · 34
XTR-380D4S	15″	dual 4 Ω	33.6	0.47	1.88	0.51	1,000	Sealed 1.17 Ported 2.05 · 34
18″ 2 models
SPL-460D1A	18″	dual 1 Ω	29.1	0.39	5.14	0.45	1,500	Sealed 1.92 Ported 5.65 · 32
SPL-460D2	18″	dual 2 Ω	27.4	0.35	5.24	0.45	1,500	Sealed 1.92 Ported 5.62 · 30

Click a column header to sort. “!” means the model’s published specs don’t add up; details are on its page.

Qts: under 0.4 — ported 0.4–0.6 — either over 0.6 — sealed · “Box” — recommended sealed and ported net volume and ported tuning.