The sound quality remains the same, with all the custom cables, right?
It's just about the quality of the cable
Well...
the subject of the difference in SQ between different cables
is one of the most debated in audio.
I have no issue in saying that I hear differences between
different cables, and I know which ones I like.
I also have no issue with those who say that there are no
audible differences between different cables.
One caveat, though - even some of the diehard "no difference"
crowd will concede that SQ can suffer (slightly) in long cables.
But if you're getting a headphone extension cable of about 10
feet or so, with high quality cable and connectors, it's
highly
doubtful that there will be any audible degradation in SQ.
Again, I'm partial to the Gotham Switzerland), and the
Canare (Japan)..
You might find this short article and the attendant
comments to be of interest in this regard.
http://www.stereophile.com/content/listening-164
Please especially note the comments, which show quite
clearly the different points of view on the continuing cable
SQ debate.