Chris, "TS" is tip-sleeve, having only 2 points of contact, as in a guitar cable (most of them, anyway). "TRS" is tip-ring-sleeve, with 3 points of contact, what is commonly thought of as a stereo plug.
Of course, it could be used that way, but has more common studio applications. You could use it for unbalanced inserts, where you basically have 2 signals going in 2 directions, as a send and return. Or it can send one "balanced" signal, which goes into electronic technobabble land involving 2 signals with reversed phase cancelling each other out and cancelling noise with them. The technogeeks here will clearly explain it until you get a headache. The thought here is that you need to unbalance your signal in order to split it for that miniplug. Therefore, they are recommending, I think, that you start with 2 TS plugs into the preamp, commonly called unbalanced cables.
I'm very techno-weak, so I won't go farther than that, lest I lead you into techno lala land. All I'm trying to do is make the parts of techno-speak that I do understand simpler, because that's the way I visualize them. It's tough being a hack. I know how to patch most stuff up intuitively, but real understanding of tech voodoo is presently beyond me. Hope that answered the small question, at least.-Richie
