Digital Audio Cables: Wire or Optical

The reason that wire is superior to toslink is that there is a lot more "unnecessary" work taking place with the toslink. As such, there is more room for signal loss and degradation.

The signal on a disc starts off as digital. When using a Toslink, it must be converted to an optical signal at the transport. It is then fed optically to the DAC. The Dac receives the optical signal and must convert it back to digital. Once it completes the optical to digital conversion, it is then converted from digital down to analogue. This can be summed up as DODAC, which would stand for Digital Optical Digital Analogue Conversion.

Using wire, you start off as digital. Leave the transport as digital. Arrive at the DAC as digital and is then converted to analogue. This is simply called a DAC process because it is Digital Analogue Convesion.

As you can see, involving optical in the digital chain adds two unnecessary steps. Which one do you think is closer to the "shortest path" and has the potential fo the "purest signal" ??? Sean
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To add to Sean's explaination, toslink is an excellent connection in THEORY. Problem exist on the receiving end of the DAC whre the optical receiver cannot cope with the bandwith and speed of the optical transmitter on the transport end causing a time delay in converting the optical signal to electrical.

This time delay or rather time error is what causes jitter. ST glass is another story much better than the Toslink.

Genesis168 wrote: "Problem exist on the receiving end of the DAC whre the optical receiver cannot cope with the bandwith and speed of the optical transmitter on the transport end causing a time delay in converting the optical signal to electrical."

Are you saying that the optical transmitter in a Toslink-based audio system is sending data too fast ("bandwidth and speed") for the receiver to process correctly? If so, do you have anything which supports this explanation?

Firstly, bandwith of TOSLINK is only 6 MHz. ST glass optical is between 50-150 MHz and electrical coax is 500 MHz.

I am not saying that the transmitter is sending the signal too fast. Rather when receiving the signal and CONVERTING it to electrical signal has a back log in doing so (takes time to do so). Transmitting will be at light speed. Receiving too at light speed but the conversion to electrical is where the problem is. Jitter is the timing error for this..we're talking micro secs to miliseconds

AT&T ST optical has far wider bandwidth therefore will better handle the signal at the receiving/conversion side.

I have read this somewhere but at this moment cannot remember where. Specs. on bandwidth is taken from "Guide to High End Audio.

Hope this helps.

In Response to Sean's comment:
Regarding additional two steps - are you saying that with coax signal starts as digital and stays digital? My impression is that it starts as digital and is then converted to some form of electrical (??) and the reverse occurs at the other end. Thus- in theory timing errors can creep into coax transmission thereby leading to jitter. And supposedly this jitter can be even MORE EXTREME than in case of toslink since the potential of RFI/EMF susceptibility of coax can be very damaging to the signal! This possibly again negates the "so called" superiority of coax over toslink. As for bandwidth, I doubt if that is even a restrictive factor. There is enough bandwidth for current signal specs.