Well, Jordan - the 'Violin' in the title is the only thing that has still totally escaped me - and I've filled the grid.
I started baffled by most of the Ring clues, then managed to wrestle out about half of the - mostly right-hand-side - radials cold; then my 'Eureka!' moment was the only conceivable solution of 17 (Rings) that came up in the Chambers app as a very obscure synonym - that gave me a hunch, and applying the *[hunch synonym] feature in the app indeed led me, too, to a rich list of over 30 potential ring entries, with only a few having 9 or 10 letters as required for 31(Ring) 7 (Ring) -and 35 (Ring) and with a sudden insight into the last letter of 33 (Radial) and enough radial checks for 7 (Ring) I was away.
But my [hunch synonym] isn't for a 'Violin' in anything I've tried - including Mrs Bradford - unless I'm being more than usually obtuse.
Even knowing the theme, and the emerging extra-letter message, the completion around the left-hand-side remained extremely tough, for me, right up to the end, with some fiendishly complicated clueing.
This one is right up there with the very best Listener setting standards, IMHO - thank you The Ace of Hearts, for a very challenging workout and a clever, consistent construction.