James, do you know what 'specs' your Utopias are going to be? Also, what is the hight of the speakers. As you know, i might try to 'scale-down' the original, if sensitive enough.
In terms of specs, the only specs I have are driver specs. YOu can see them at www.focal.tm.fr I am going to use the ATLR, Audiom 6W and 33WX. The real Utopias are 1340mm tall.... mine will be around 1380-1400mm depending on how tall I want to make the base.
THE ATLR is 95db, 6W - 96db, and 33WX - 94.4db. Quite sensitive. I am expecting atleast 93.5-94db overall sensitivity once they're in the box. :-)