Thiel Owners

^It’s all about using the right tool for the job at hand. A different particularly fine tool might be better for a different job.

@vaan whatever you choose make it 400 watts minimum at 2 imo 

^A minimum of 400 Watts into 2 Ohms is excellent advice. Depending on ones room and desired volume output, multiples of that power output into 2 Ohms could be appreciated. As far as preamplifiers go, much of it depends on the specific amplification and source components used, it’s possible that you might not even need one.

Tom, with a tri amp setup, do you hear other benefits besides better matching of the amp to the driver?
Regarding amp preferences for the 3.7, it all depends how loud you want to play and how big your room is or distance from the speakers. The 3.7 is rated at 92 dB for 1 watt and pretty efficient. The stability of an amp at 2 ohm is relevant but the need to double power from 4 to 2 ohm is only meaningful if you use the maximum output. I based this on experimenting with the bryston 7bst, which allows to switch from parallel to serial, with a minimum impedance cut in half. No difference at any level below 90 dB listening level.