To power condition or not

Try both. I have never had a problem with ATC Actives - dead quiet even with your ear right over the tweeter. It is crucial that you use XLR - a good cable in Canare Star Quad. If you use inferior RCA and adapt that to XLR adaptor then you can of course expect a much higher noise floor.

Whatever way you choose to go, get a couple Perfect Path Technologies E Mats to put on the inside of your electrical service door.  They will improve the sound of everything in your audio system as well as your video and all things electrical in your home.  They are the type of thing that once you have them and hear and see the improvements they yield you won't be able to do without them!

Depends on the total draw of all your devices and the capacity of your household circuit and that of your Furman, which is matched for a 15A circuit.  The Furman manual states a 1300-1700W work capability---about the same as a 15A circuit free of other devices and appliances.  It may be best to limit the demands on your Furman to either the amps in your new speakers or to your other amp or amps, but not both.  Have to favor your front-end devices overall with a mid-size power-on-demand conditioner on a 15A circuit, if that is what you have at the wall.  Could try it all via the Furman at low volume--then try higher.    

Shadorne,

Will have high quality RCA to XLR cables made, no adaptors.  German manufacturer or Analysis Plus expected.