Thank you for this nformation. That makes perfect sense. What I glean from this is that the DAC in the Sony is not that good, because the 4x downsampled file played through S/PDIF coax sounds noticeably worse than the full resolution version, in my opinion. I can't usually discern this sort of thing on my equipment. I was fooled, because, usually, if the DSD version and the redbook vesion are from the same mastering, I don't readily hear the difference. On that particular disc, the masterings are different, so my assumptions were wrong. Sounds like the HDMI converter is the way to go here.