Spending $8K on cables is not the way to go. If you REALLY want to experiment, use the lending library at thecableco.com and look at other brands like Acoustic Zen. Their top of the range is $4K - the silver may help. I bought my AZ Hologram II used for $900 and I love them.
Also look at brands that sell direct, and buy an $8K cable for $2K (generally speaking). All my IC's are Zavfino Fusion.
But maybe the Mac is the real issue. I learned the hard way that amp and speaker synergy is pretty much everything. Sources are much easier really.