James Crabb is a musical magician, taking the ever-unfashionable accordion into new and unlikely places, through bespoke arrangements of a spectrum of pieces which brim with wit and inventiveness. This lunchtime concert with violinist Anthony Marwood was a sheer joy, as they together traversed a range of style and tone, richly entertaining a very decent Bank Holiday crowd in the Wigmore Hall.

"How long is Wagner’s Ring Cycle?" That’s not the opening to a joke, it’s a genuine question asked by a friend who I’d met up with before heading to Edinburgh’s Usher Hall to hear the Royal Scottish National Orchestra perform "Wagner’s Ring Symphony". His question is one I really don’t know how to answer: technically it’s 15 hours, but does a cycle ever really end? Is a piece of string as long as the ties that bind? How long would it take to wrap up the whole world?