Well, I did get the chance to audition my 3.6's with a couple of amps yesterday. My first thoughts were amazement at just how well the CS3.6's can sound! :^) In addition to listening to one of my GFA-555II's, I auditioned McCormack DNA-225, Theta Enterprise monoblocks, Theta Intrepid, and EDGE NL-10. The DNA-225 quickly dropped out of the running. It's tonal balance was fine, and its low end control was very good, but it seemed to fall on its face in the imaging and depth/width of soundstage. In truth, the 555II noticeably exceeded the DNA-225 in all of these regards (which shocked me), although the Adcom was otherwise clearly outclassed by the McCormack. The Theta Enterprises sounded absolutely marvelous. Great tonal balance, and a level of detail, imaging and soundstage that blew me away, with controlled, natural low end, and a bit of a high end sheen. Very musical for a solid state amp. The Enterprises really showed me what the Thiels could do. Ideally, I wanted to hear a Dreadnaught II with the 3.6's, but all they had was an Intrepid. Talk about an eye-opener! That 5-channel, 100 watt amp has no right to sound as good as it does with those 3.6's! Especially considering the price. It most definitely captures the "Theta sound", and while it lacked the level of detail, separation, and depth of soundstage that the Enterprises offer, its tonal balance, width of soundstage, and low end performance were remarkably similar to the much costlier monoblocks.
At a different location, I had an opportunity to audition the EDGE NL-10. This is a very fast, neutral amp. It pushed the 3.6's with ease, and really brought out the best of their dynamic ability. Given that I was in very different rooms, with vastly different associated gear, it was difficult to really compare the NL-10 to the Enterprises, but I can definitely say that they are in the same league. Both made my Thiels do things that I had never heard before. If I had to try to articulate a comparison, and considering all of the other variables, I'd say that the NL-10 was noticeably faster, and had extreme dynamic control, and was quite possibly more neutral, but the Enterprises were more sweet and musical, and had perhaps a bit more low end fullness.
While I haven't completely ruled out EDGE, I am thinking of using the Intrepid for my center and surrounds, and either getting a 2-channel Dreadaught II or the Enterprises for my 3.6's. Yes, going the Enterprise route pretty much blows my "affordable" thing, but they really did make those Thiels sing.
Tom.