Why do digital cables sound different?


I have been talking to a few e-mail buddies and have a question that isn't being satisfactorily answered this far. So...I'm asking the experts on the forum to pitch in. This has probably been asked before but I can't find any references for it. Can someone explain why one DIGITAL cable (coaxial, BNC, etc.) can sound different than another? There are also similar claims for Toslink. In my mind, we're just trying to move bits from one place to another. Doesn't the digital stream get reconstituted and re-clocked on the receiving end anyway? Please enlighten me and maybe send along some URLs for my edification. Thanks, Dan
danielho
I will be honest and say that I do not use fiber optic cables so I can not say definitively there is a sonic difference between digital cables. You have heard differences, so I will take your word for it. As for the reason.... I am an EE not a physisist. If I were to take a stab at it, with my limited knowledge of optics and lightwave, I would guess the differences would be due to propagation delay, loss or refraction differences in the cables. Maybe someone else with a better understanding of optics in this forum could enlighten us both.
Don't worry about starting a religious war. The reason for these forums is to get the big picture. There are a million opinions out there and you should consider the ones that make sense to you. Part of the fun of these forums is to learn a little and give a little in return. I read a reply to one of my posts the other day that mentioned that audio was a "passionate undertaking". I subscribe to this wholeheartedly because if the music we listen to and the equipment that provides that music does not empower emotion and passion, why listen at all? If some of the responses seed a bit emotional, just understand that it is only because of the passion that we have for the music.
Frogman, rather than challenge the fact that you hear the difference I will simply state what I know to be facts. While I most certainly do not have the trained ears of a musician, I think, (maybe wrongfully so) that God has blessed me with a decent set of ears. While I have not listened to a set of fiber optic cables, I can not discearn any real sonic differences between good quality copper (or silver etc.) cables. I also submit that the physics involved may not support sonic differences that are discearnable to my ears. I believe you when you say you can hear the differences, but maybe the differences are so subtle that one would need musican's ears to hear them. To quote Dennis Miller: "that's my opinion, I could be wrong".
Gmkowal I don't believe that you understand the signal transfer in CD playback. Most other digital transactions people have discussed are NOT real-time. CD playback is real-time. The protocol is one way with 44000 transmissions per second. Signal is lost. Bits are dropped. On other real-time digital aplications, say telephony, there is both a retry mechanism if the protocol allows and data recovery. CD protocol has no such provisions. Again rember this is technology that is almost 20 years old. The improvement in technology since the CD standard to the present is greater than the improvement in technology from Mr Bell And Edison to the start of CD technology. I suggest that your claimed knowledge of physics is flawed by your lack of understanding of this signal transfer. Before you go blasting a lot of other people, you'd better know what yo're talking about. As for some backgrtound, I've been working with digital audio on and off for over 30 years. I have spent over 8 years designing commercial digital audio and video and data transfer interfaces. So I'm not someone who has just read a few articles in StereoShill.
Gmkowal just a follow on my previous response. If you don't believe me, prove it yourself. Attach a scope to the output of your DAC. Play some test tones on your transport, ( Use frequencies above 8k that's where the effect starts to be more noticable). Get some different cables and measure the signals that come out of the DAC. I have measured some pretty significant differences. I've always believed if you can measure the difference, it exists.