Thiel Owners

If you choose the 3.5s, be sure to get the equalizer

If you like deep bass, can be happy with moderate loudness, and don't want to worry about having a high power amp, the 3.5 Will Serve you well. Replacing the thiel equalizer  with a 31 1/3 Oct. With a dbx 1231 or a Rane mx60 is a good option.

Thank You -guys for chiming in here.  Happy Listening!

The one series is made for small spaces, moving a fraction of the air.
Woofer areas are approximately 1: 10", 2: 50", 3: 75".

With a  room that size, the 1.5's will be too small. You're not going to fill the room sufficiently. The 3.5's requires an amp with LOTS of current and the ability to drive a 4 ohm load with ease. As long as you have that, it'll be very rewarding. And of course make sure you get the bass equalizer, an absolute necessity with the 3.5's