As happy owner of a pair of Thiel 3.6, and two beefy amps, McCormack DNA2 and Threshold S500II, I would say that both represent a very good match with this hard to drive loudspeakers, with a slight preference to DNA2 when I go for low volume level listening in night time, impressive dynamics and details retrieval. Anyway both very recommended, even for their reliability that matters a lot due to the age these amps can be found on second hand market, never a problem or sound quality worsening.