In my opinion, there are no absolutely neutral cables. You cannot transfer audio signal from one place to another without altering it somehow. What you really need is a cable who's signature is neutral enough, that you are not bothered by the bias. Starting from that goal, I would try Purist Audio Design's products. Either the Proteous or Dominus, depending on what you can afford. Both of these cables are state of the art, and are my personal favorites. Will you get other excellent suggestions? You bet, and depending on what "bias" is your favorite, or least objectionable, the answers could be better than mine.