Mr. P hit the nail on the head stating the average person can't tell the subtle differences in high end. I think that you need to be a person who listens to music all the time and is in tune with the nuances.

Sir T, I agree that for the most part you need a high end system to be able to tell the differeces between cables. But, my son and I were easily able to tell the difference between a pair of BJC IC's and a pair of AudioQuest Corals in his system which consisted at the time of a Class D Audio CDA254 digital amp, a modded cheap Maverick Audio Tube Magic DAC/Preamp and a pair of PSB B6 speakers. The BJC's was too bright sounding while the AQ's were less bright and more pleasing with out sounding rolled off. The difference was not subtle. That system cost about $1300 and sounded awesome.

By the way. I do all my critical listening in the dark or with the lights down. I am more in tune to the music without visual distractions.