Which is better, your audio from a optical cable or a hdmi cable?

Digital is digital; as long as the signal is getting from one end of the cable to the other, it's as good as it can be. Many people here are are confusing a digital audio signal with an analog audio signal which can be greatly effected by cable material. The only thing that would make optical superior is its inability to accept RF interference.

The only instance I would use HDMI with optical audio would be if I were using an A/V receiver with only HDMI pass-through capability, at which time in order to get audio to my receiver I would have to use optical or coaxial digital audio (whichever my system facilitated) from my TV to my receiver.

My receiver doesn't facilitate HDMI so I have my up-converting DVD player hooked to my HDTV with HDMI (to keep the video signal in the digital realm) and a coaxial digital audio cable from my DVD player to my receiver. There's no sense in taking an HDMI digital audio signal and converting it to optical at the TV, and sending that to the receiver when I can just send a coaxial digital audio signal directly to the receiver from the DVD player. optical if your receiver can take it (nothing is faster than light). hdmi just runs video and audio together Hi Def I believe you can get better bandwidth (ie more data for clearer and better sound) through the optical. they're the same. It's just two different methods of sending a pure digital signal. HDMI's pro is that you can carry digital video on the same wire. It was created to get rid of some wires in your setup so it's not as cluttered. If you like the optical, you can go that way too. They have exactly the same result because they're both transferring LPCM audio. just use what's most convenient for you.