Optical or coax?

Are you talking about real glass fiber optical (AT&T ST) or plastic* optical (Toslink)?

* Toslink is available now made w/ glass fiber, but still has the same limitations as the plastic stuff.

OK, if you are referring to the Mcintosh MC861 DVD player, I would definitely recommend using a high quality digital coax. Its "optical" output is Toslink, and although you can get the ICs in glass fiber (as opposed to the standard plastic fiber) it's the transceivers (the thing they plug into on each end) that limit their performance. Also the Toslink cables themselves (glass or plastic) aren't good for much over ten feet if I remember correctly (AT&T can go for miles.) Anyway that's my 2 cents.

Jcc3 -- I believe that w/ your Krell stuff, you're talking about AT&T ST glass fiber optical connectors, and not Toslink. And to clarify the electrical thing, it's not so much about carrying a charge but rather that fiber optic ICs (Toslink OR AT&T) are not conductive and therefore the equipment is electrically isolated from each other -- sometimes an advantage when hum problems arise.

As for the glass (AT&T) vs. coax or AES/EBU issue, it really depends on the quality of the cable in both cases. If you are talking about premium examples of either kind, for instance, Aural Symphonics Optimism 2 AT&T glass fiber ($1000) vs. Purist Dominus or Siltech coax or EBU (>$2500), I would have to say go with the glass (AT&T, not Toslink) if your components have AT&T inputs/outputs.

In a choice between Toslink and coax, I'd say go with the coax if it's reasonably high quality (in the $200+ range.) If it's just junk coax, you probably won't hear any difference between the two.

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