This just made me remember about a company that created their own interfaces (not thinking Krell CAST, but something else) between preamp and amp, and chose BNC 75 ohm connectors as a result. Used to read about it, and the positive aural benefits, in Bound For Sound. Forgot the company, though.....they made some big honkin' SS amps.....
EDIT: found it, PBN Audio, they use BNC as optional connectivity, like their Olypia preamp