Hi,
First post here.
To my ears there clearly are differences between some cables, but not between others. I have heard these differences in my own system.
In my experience, cost is not by itself an indicator of how 'good' or 'different' a cable will sound. Indeed, I am sure some manufacturers dress up their cables in fancy jackets and boxes and have a laugh with the price tag. Their cables may sound indistinguishable from freebies.
From the cables I have heard NVA are by far the best. NVA SSP interconnects and LS3 speaker cable is obviously differently (and superior) to freebie and bell wire.
DF