I experienced a fascinating comparison in one of the RMAF rooms featuring systems from Colorado dealer ListenUp. With Sonus Faber Cremona Elipsa speakers (review forthcoming) driven by a combination of Musical Fidelity X-T100 integrated amplifier "supercharged" with MF's 550K monoblocks, and Shunyata AC conditioning and power cables, CDs played back on MF's new top-loading CD player were being compared with lossless-encoded files of the same recordings played back over WiFi via a Sonos ZP80 that fed its S/PDIF digital output to the MF player's DAC section. The data were the same, so other than the WiFi connection, there was no reason for the sound to be different. And I did indeed find it very difficult to hear any consistent difference between the two presentations. Perhaps the low frequencies were a little better-defined and extended via CD, but I don't think I could have identified that without knowing which was which. Interesting.