I had some experience with the Dynaudio Consequences, many years ago, and I still consider selling them cheap one of my biggest audio mistakes. But at that time I did not have a dedicated listening room and as they need a large distance between the speakers and the listener, the best listening position was at the place occupied by a large dinning table
I heard some of the best sounds in my life with the Consequences and the Primare 200 system I am now advertising at Audiogon in a 80 square meter room, but the Krell amplifiers (KSA300s and KAS at that time) and Cello's were the best with these speakers. The Dynaudio Arbiter's and the FM Acoustics were only dreams for me, but a reliable friend who heard them with the Consequence's is still recovering after 15 years.
From my many experiences, including Audio Research Classic 150s, I would not advise using them with tubes, independently of power or electric compatibility. I have now a speaker with a similar behavior in my system the wonderful Krell LAT1000s. They are a great speaker with the Dartzeel amplifier (200W, current limited) but my VTL 750s even in pentode mode can not control them.
I would advise you on upgrading your FBP600 to 700cx they are completely different amplifiers, the 700cx is much faster and it should complement the Consequences much better. Also something tells me that the conrad johnson premier 350 a great LAT1000 driver would be a good match, but is also only a guess.
