I'm actually quite serious, of the people who are buying really hi-fi audio inputs, it's not unlikely a large number of them are quite interested in the actual

I'm actually quite serious, of the people who are buying really hi-fi audio inputs, it's not unlikely a large number of them are quite interested in the actual bandwidth of the input. They're using that sampling headroom for something else (oversampling). Regulation and stabilization is a whole ""niche"" area of electronics called "voltage regulation" and yes, you can improve it a lot (and you can only do your best regardless of instability of the base). Actually a lot of audio engineers would be feeding it clean (linear regulated) power in this case as well. My Astron linear supplies are quite clean for radio and would be excellent for audio too. https://www.eham.net/reviews/view-product?id=1616 https://www.eham.net/reviews/view-product?id=1616 https://www.eham.net/reviews/view-product?id=9570 https://www.eham.net/reviews/view-product?id=9570 USB optoisolator + linear regulated supply on a hub on the other side is something I've seriously considered for a nice SDR setup even short of that. Again, of the people who buy this stuff, yes you will find a lot of people paying attention to the details and buying/building esoteric setups. Hams exist and the hobby almost inherently involves opening up the checkbook lol. Even decent audio gear is generally going to be $500-1000 most of the time.