Optical has to go first from the S/PDIF electrical output to a laser-diode, which transmits the signal as light pulses over the optical cable, then optically sensed at the other end and converted back to the base electrical S/PDIF signal. The toslink technology, however, is transparent, (read "it works") so it should make NO DIFFERENCE which link you use. Toslink is free from hum and interference in theory, but in practice, both kinds of connections are just fine, and the kind of XLR cabling is entirely unimportant, in counterpoint to strobl's answer. PROOF: All these Internet webpages and emails go digitally over miles of unshielded twisted pair phone lines, converted to high-bandwidth fiber optic and back, etc.etc. and one asks if the phone companies and ISP's using "silver coax" to "improve" the signal? You CD's S/PDIF output at 44.1kHz is no different than your modem's 56kHz signal. Is strobl buying silver interconnect from his computer to his phone jack? HA! I doubt it!
