I own the Khorus. It is a great speaker that seems to work well with a wide variety of amplifiers. They has a soundstaging and imaging ability that I have never heard in a speaker before. They are also able to produce inner detail like no other speaker I've heard. The combination makes this speaker incredibly holographic. And they do this while remaining extremely musical. I replaced Von Schweikert VR6s with them, and have never looked back. They have a very long break-in period, and don't sound good out-of-the-box. There are now two excellent reviews out on them at Stereotimes and Soundstage. There are also many posts about them on this site, so I'm not going to duplicate what has already been said. As far as the subs goes, I have never felt that I have needed it for bass in my room. I get floor and wall shaking bass out of them. A friend of mine has two subs. His room is larger. He says that the use of the subs improves the speakers because they no longer have to deal with the low frequency extension. When you use the subs, you have to block the rear port. This supposedly improves the performance of the Khorus from the mid- bass up. That is the only reason I might do it. I haven't tried it, but I probably will, given my friend's enthusiasm about them. The use of one or two is dependent on room size. He started with one, and bought a second.
