My friend has a room about 1/3 smaller than yours. He had similar issues, and tried various things. His current setup consists of an ARC Ref 3 + Pass X350.5 on the same Finite Elemente rack. He's using Purist Audio cables. I believe he had tried several top models of Nordost cables and didn't care for them.
I've been listening to his system at least once a month for the past couple of years with various changes he's done with equipment, tweaks. I think the best improvements came in this order:
1/ Speaker placement
2/ Room treatment
3/ Equipment/Cable upgrade
Anyways, I can say that his system is sounding much, much better these days compare to when he first got them home.
He's been using those Finite Elemente Cerabase under his C4s. He swears by it. But I've spoken to someone who tried them under Verity Parsifal Encores (my speakers) and the guy said that he didn't hear too much of an improvement.
FrankC
I've been listening to his system at least once a month for the past couple of years with various changes he's done with equipment, tweaks. I think the best improvements came in this order:
1/ Speaker placement
2/ Room treatment
3/ Equipment/Cable upgrade
Anyways, I can say that his system is sounding much, much better these days compare to when he first got them home.
He's been using those Finite Elemente Cerabase under his C4s. He swears by it. But I've spoken to someone who tried them under Verity Parsifal Encores (my speakers) and the guy said that he didn't hear too much of an improvement.
FrankC