Thiel 2.7 VS 3.7???

While I have not heard either of these Thiel models, there are a lot of Thiel owners on the forums, so I'm sure they'll chime in. The one observation I'll make is some of this will depend on the size of your room; if it's smaller, the 3.7s might not sound their best--I found this to be the case between the Thiel CS2 and 3 models I auditioned years ago. You probably should give the dimensions of your listening room, as well as the amplification that you are using, to get a more informed answer.

Seems to me that you have both enough room and amplification for the 3.7s. I agree with Vhiner about the sub, the Thiel sub would be the way to go if you take that choice.

Since no one has mentioned it yet, again I'll venture a guess based on my past experience with the Thiel CS2 and CS 3.5 (as well, frankly, as in the cases of other speaker lines, like Dunlavy, when you went up the line to larger speakers), and see if anyone else can chime in. The big differences in the past between the two classes of speakers to my ears were both in bass quantity and quality and, more importantly, a better sense of ease in presentation from the bigger speaker and an overall bigger sound. The drivers moved more air, weren't working as hard and overall had a more relaxed and open sound, less strained. I know the 2.7 is really light years ahead of the CS2 and is probably one of the best Thiel speakers, but the 3.7 is a good deal better than the original CS 3.5, much as I liked that speaker, and is very highly regarded. I would think that ease, particularly in loud and complex musical passages, would be noticeable--it certainly was to me. If you listen more to smaller scale ensembles and music and at moderate volume levels, it may not be as important a difference. Just a guess based on past experience--I'm hoping someone who owns or has compared the actual speakers will add their two cents.

I have a JL Labs sub and feel it works very well with my Nola speakers. I'm sure that you can get one to work with your speakers, too, it has a lot of adjustments you can make. I still think the Thiel sub might be a better choice, though, as it has a passive crossover that was designed to integrate with Thiel loudspeakers.