roberjerman cannot hear these differences, so he makes claims, these differences do no exist. They do exist, just listen for yourself, and with the system you put together, it will not be hard to hear.
Obviously roberjerkman's system or equipment is not good enough to hear differences, or he has not learned how to listen for differences.For years i was in the same situation, It was my equipment.
I promise you there are differences in the sound of cables . It may not always be easily discernible and obvious. You also have to learn how to listen for differences. Your brain cannot always listen to or pick up all differences at the same time ...like soundstage depth, height, imaging ...
Then you have dynamics , Attack, Decay, Sustain and Release. Then you have to listen at all the different freq Ranges.Some cables present a more laid back presentation... Some are more of a front row , up close presentation . Some have extra energy in the upper mids. or some in the mid bass. some have a much more prominent Bass Some are more detailed..etc..etc.etc.
It does take some education or experience as to what to listen for.
this can help
http://djfrobot.blogspot.com/2010/04/eq-frequency-chart-for-instruments.html