A hardware upgrade will make the biggest improvement. Cables have an effect on sound that is for sure but it is not nearly as big as some would have you believe. I recently called the manufacture of my amplifiers and asked what they recommended. To my surprise, the guy laughed and said any well made cable, but he suggested that I not spend much and buy cable last as it would have the least effect upon the sound. He suggested that I apply better acoustical treatment to my listening room as this would have a bigger effect than cables. Though he did recommend some decent brands of cable and had some decent stuff in his personal set up, though nothing very expensive.
