Broadening stream of virtual performances ranges from master classes to masterworks

Digital Preview: With another Artic blast on the way, it’s a good time to check out the world’s top fine arts events available live or on-demand — Joyce DiDonato’s master classes at Carnegie Hall, a “Ring” in Vienna, a new cello concerto in Detroit. And the Lyric Opera of Chicago has just finished recording its new “Bel Canto” for a future PBS broadcast.