beautiful it looks, for the sound, must be nice too if you look at the space and the shape.
for decoupling from a dirty mains with spikes I can recommend these:
http://www.ismet.de/Product-Pages/su...uSL.StV158YtKC
obviously if the mains is crap a transformer will do not much good. Maybe the wiring inside the house needs changing?
I had to wait 3 years to move into this room, and worked in a space as "big" as 2.5 by 2.5 mtr.. And everything was in there LOL. Fullrange speakers, DAW modular synth keyboards some outboard, crazy, MAD. so I hope you are not going through the same..
Space is the hardest to find commodity here I guess. But you are like me in the centre of an old city, which makes up for it too I guess. I am longing for the moment I can build a studio by the mediterranean. We all must have dreams, right

Next lottery here is at the 10th of the month...
You too the very best waves!
edit: I wanted to post a link to that new york studio that was built entirely for them by carpenters. amazing, with a dome and a mic hanging way up there...
couldn't find the link, but it was all wood too.... there was a video on that studio video site, give me a moment, I'll find it. you can see a lot of different rooms on that site. now where is it...