I can assure all of you that there is a huge difference between optical and digital cables, just as there is a difference between all conductive materials whether they be copper, silver, gold or light! Just because a system is digital makes no difference at all - yuou talk of ones and zeroes but this is a huge oversimplification. If this was the case then all CD and DVD players would sound the same which, frankly, they do not. Digital signals must be translated to analogue for the human ear to hear them and this is where subtle variations can be achieved. Cables have been a moot point in Hi Fi for some time but can drastically alter the perceived sound of a system. Different cables can make a sytem sound sluggish or bright or dynamic or soft - depending on what is used. I have tested over 100 cables in various dufferent systems and it is possible to detect not only large differences but subtle variations as well. If you find your system is not as detailed or as dynamic as you would like then instead of purchasing a new amp or set of speakers a change of cable can be all that is required in some cases! With regard to 75ohm coax cables I prefer solid core cables such as the Chord Silver Prodac from the UK - if you can get it then it is one the best cables around. Shielding is not a problem as this is a balanced cable - as are the majority of 75ohm coax cables!! I do stick to my statement that most cases a coax of an equivalent price will sound 100 times better than the optical. The test, as always, though is to use your ears. Go to your dealer and ask them if they will give you a home demo, or loan you, a set of coax and digital cables (you may have to leave a deposit) take them home - plug them in and enjoy! Take care with solid core cables, however, as they can break - optical is in fact more robust! Good luck!