@thyname @denon1
you were right; The TWL Obsession is a fantastic PC and has improved the performance of the system. I tried a Nordost Brahma (bought from a friend and ended up using on the C-900 preamp), Audience AU24SE-HP, Shunyate NRC something, stock, Wireworld Aurora, Analysis Plus Ten; The improvements that I hear described in a few words: effortless dynamics--transient attack is tightened up, decays/trails bloom better, sound seems "detached" from the actual gear; overall refinement and beauty to the sound...I think i'm in the middle of the trial run but I will be keeping this PC.
I ordered a Triode Wire Labs American Digital to test on the DAC. That arrives in a few days.
The construction of the TWL Obsession is top class. The connector bodies are chunky and machined. The cable is very easy to route because its super flexible. Helps for cable management. Thanks for the solid recommendation.