Maybe 4 years ago I bought an Oppo 105 to play SACDs not realizing it does not output SACD, but plays it only when using the variable VC, so I used balanced cables, but wasn’t happy with it when playing red book cds.
So I inserted my backup, a highly modded Pioneer PD 65, with outboard PS. It had toslink out but not coax out, so. I bought a WireWorld Starlight toslink cable
I decided to upgrade the 105s power supply in expectation of using it for both, but was using the Starlite toslink for redbook. I still wasn’t happy, but was unaware that coax was superior (at least at this level). The Pioneer laser died and parts are no longer available.
Being on a tight budget, I was not in the position to buy the much heralded Jay’s Audio transport, but I contacted them to ask why no toslink, at which point I learned of its inferiority to coax. So, I did my homework and bought a Marantz HD CD 1 to use as a transport and eventual backup. Again I used the toslink, but finally, I bought a hq WireWorld coax and was shocked. This is the kind of sonic upgrade I would expect from better components, be they amp, pre, dac...
Even though I knew cables/ics matter a lot, I was not up to speed when it came to toslink v coax. Lesson learned.
I am now back using the 105 for redbook and needing to use it direct to amp when listening to SACDs