I agree completely with Mr. Reynolds. I use a Velodyne HGS-15 with SMS-1 to supplement my KEF 104.2 mains. I find that the KEFs sound fine by themselves, but when used with the sub, they sound a bit more transparent if high-passed at 80 Hz. Maybe something about double coverage of the mid low range. Even careful listening cannot identify the sub as a separate source, except you realize the KEFs could not produce certain sounds, especially that felt more than heard vibration when a large pipe is invoked, the feeling you get at a live organ recital.
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