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
Here is my digital cable upgrade path over last 3yrs, getting slightly better sound each step at lower prices:

AZ Mc2 $300 --> WW Supernova III glass toslink $100 --> Sonicwave glass toslink (280 fibers) $25 --> Stereovox HDVX $100 currently used.

Still have my $25 glass toslinks around one of best examples of "bang for the buck" ever in my cable buying experience.
Over spring break, I had a chance to listen to my Rotel/coax vs. my Panasonic/optical.

The first impression was one of much more oppeness, and a deeper sound around instruments with the optical output.

*HOWEVER*, cymbal crashes, esses, fingered strings, etc all sound FAR better via the coax!

For highly digital source material, like "The Matrix," the optic input adds a nice effect, making everything "feel" digital. It also seems to portray a tad mote bass (but it actually just muddies it up, when compared a/b).

I used my own, and a friend's copy of the Rolling Stone's "Love You Live" disc, and could simply switch between the two units on my Rotel DAC. The crowd sounds bigger, the clapping more real, and the music more convincing via the coax.

I'll admit I was hasty the first time I posted, and I'll think twice, er, listen twice before running my mouth next time!
I was one of the original people to post on this topic, almost 3.5 years ago. My position, that any "properly constructed" digital cable should be indistinguishable from another was predictably met with scorn and ridicule. My ears and even my choice of a mate were questioned. Not that the later has much to do with the topic. Unfortunately, some people when confronted with someone else’s views that don’t agree with their own can’t stay objective.

While I still hold my beliefs, let’s look at some of the other factors that might be in play.

Joemazzaglia makes the point that when he heard optical fiber and coax cable through the same unit, there was a big difference, in favor of the coax. I believe that he heard that difference and it is not surprising. A number of manufactures warned that maximum fidelity could not be obtained from the Toslink connections using their equipment. I believe that is because they hadn’t optimized for optical digital transfer.

There is also the issue of true optical glass cable, vs. plastic. I’ve purchased some true optical glass cables and their performance clearly exceeds a cheap plastic one I bought as a comparison.

I would be interested in whether Joemazzaglia would notice the same difference
if two or three coax cables, all true 75 ohm and made by reputable manufacturers were compared in a blind test? That would say more about the cables, since they are of the same type.

My own experience with a very fine DAC the Levinson 30.6, which has coax (SPDIF), balanced (AES/EBU), as well as Toslink inputs is that the type of cable shouldn't matter. I have compared AES/EBU digital cables from Cardas and Madrigal, with SPDIF cables from Kimber and Madrigal and true Corning fiber optic cables through the Levinson and have not be able to detect any noticeable differences. (The cheap plastic cable notwithstanding)

While none of these cables was a bargain basement item. They are also not cost is no object (or maybe cost is the only object) designs. They are all good well engineered and manufactured products that do exactly what they claim to which is move digital data from one component, the transport, to the next, the D to A converter. They do so properly and predictably and the DAC then can produce the analog signal it was designed to.

I think people need to remember, digital cables transmit 1’s and 0’s. They don’t transmit anything that a speaker would make into sound. That all happens after the DAC converts the signal to analog.

Also, my argument wasn't that any piece of copper wire from Radio Shack will do as a digital cable. I was pointing out that once a design has "got it right", which can be achieved as fairly moderate cost, “Gilding the Lilly” by adding meaningless features (super fancy connectors, braiding around the insulation come to mind) that add cost but change nothing about performance doesn't make the sound better.

I also understand that pride of ownership may make us prefer the fancier cable and if that is so and we can afford it, go for it. But don't try to convince ourselves or others that the sound it can produce changed.

I know that will probably start another round of name calling and if so, so be it. We have a right to our opinions, but I find it discouraging that people attack when confronted with ideas that they don't want to accept. Also too much is made of too little in this hobby. I hate to see folks be convinced that they can buy something that isn’t there if they just spend more money.

Check out bryston's website.They have a simple yet accurate response to your question...
As there are in power cords great differences are to be heard in digital cables..Much to do about time and phase coherency. Tom