@curiousjim
A few years ago, Steve Plaskin (with AudioStream at the time) posted about using fiber converters and 1M of fiber as an isolation technique to reduce noise. Based on that review, I purchased 1M of cable and two converters, and then later installed my entire 45-foot run with fiber since I figured having only one SMPS near my system was better than having both near my system. Before long, I switched to LPSs. I cannot remember how I came on the products that I used, and I am not the right person to ask about which specific converters would offer the best performance but these are what I used:
For a while, I thought music sounded a little smooth/calmer using fiber from my router to my system, but then when I started trying other isolation products such as the Network Acoustics eno, and later the muon, the effect of using fiber seemed to be no longer necessary and I found that going back to Ethernet cable only for my 45-foot run (CAT8) may even sound slightly better, although the difference seems almost imperceptible. Your plan to start with the converters and then if you like the sound, add LPSs is a good way to start. FWIW, the iFi power supplies I believe are highly filtered SMPSs but not LPSs. That doesn't mean they are not quieter. However, my understanding is that there is a big difference between the iFi SilentPower and the more expensive iFi Power elite. Good luck.
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