Siltech G3 X Purist Audio Colossus

Please,I need some advice in interconnects upgrade.

My system:

SME 10A + Koetsu Red Signature
Accuphase DP-65V
Pass X-2 Pre Amp.
Pass X-150 Power Amp.
Apogee Caliper Sigs.Speakers
Krell Cogelco Yellow Int.
Siltech LS-80 G3 Speaker Cables

Thank you