Now I know what they mean by a bright cable.

Have an Integra Research RDC-7 pre amp with balanced outputs. When I first got it I used Better Cables XLR balanced for my front two channels and it sounded great. However I fell in love with a DH Labs Air Matrix ad and swapped them out. Long story short the DH Labs in my system is so bright, the music sounds unnatural and definetly causes listerner fatigue. I swapped back the better cables and the difference is unmistakeable. Perhaps the DH Labs might be good on tube equipment but wow it sounded like nails on a blackboard on mine. What causes a cable to sound so bright? Is is silver vs copper?