XLR or single ended cables and why?

Balanced audio interconnects (XLR) utilize two conductors, while standard RCA audio interconnects use only a single "unbalanced" conductor. This enhanced design gives balanced audio interconnects the power to provide greater resistance against sources of noise (RF, EMI, etc.). The result is a more pure signal transfer, especially in longer-run applications.

You may or may not hear a difference between XLR and RCA in short runs, however XLR should prove quieter on very long runs or in set-ups where many cords come in contact with each other...think rock concerts, where all instrument and mic cords are XLR.

Reb1208 and Andrewdoan, my statement was copied directly from the Cobalt Cable website. Any errors are due to the info published by Blue Jeans Cable...

If nothing else, it convinces me that not all cable manufacturers...or perhaps just the marketing departments...know what the hell they are talking about. I'll certainly cross Cobalt Cable off my list of potential suppliers.

Well, the concept of noise reduction is the basic theme of XLR/balanced cable, and that point is the "take away" regardless of how badly anyone messes up the explanation of how it is achieved. At least, that's my approach as an end user. If I owned equipment that was all truly balanced, I'm certain I'd use balanced cabling. However, as it stands, I use all single ended cabling, and I have absolutely no issues with noise due to the RCA interconnects.