That dacs make a bigger difference than what transports do, when reading CD's and using spdif proper 75ohm BNC connected coax, as RCA are not 75ohm.
@georgehifi
Baring false advertisement, why would RCA not be 75 ohm when blue jeans cable states (https://www.bluejeanscable.com/store/digital-audio/index.htm) ?
"Connectors are a critical part of any cable, because if the coax isn't well-joined to the connectors, or if the connectors don't make firm electrical contact with the jacks, it doesn't much matter how good the coax is. For mechanical stability and electrical performance, there's no better RCA plug available than the Canare RCAP. These Canare plugs are designed for the best possible impedance match with 75 ohm video coax. "