Janáček’s From the House of the Dead is a contender for the most depressing opera in the repertoire, and Covent Garden’s new production doesn’t do a lot to cheer it up. Transferring the action from a Siberian prison camp to a modern, possibly American penitentiary, the director Krzysztof Warlikowski delivers something that not only looks bleak (which isn’t inappropriate) but is messy and pretentious. Not a winning combination. With a teeming cast of small roles – few of them providing any chance to shine – House/Dead is ensemble opera, about atmosphere rather than narrative, and challenging for audiences at the best of times. But in this fussily undisciplined staging you never know who anybody is and don’t much care: an indifference intensified by the way Warlikowski makes so little of Janáček’s guiding idea that there is “in every creature [even the wretched of this prison camp] a spark of God”. That message gives the opera focus, hope and bearability. But here, it doesn’t register. What does, more happily, is strong, assertive singing, notably from Johan Reuter. And Mark Wigglesworth confirms his reputation as a first-rank Janáček conductor, handling the music’s oddities with mastery. But that’s another way of saying this is a production better heard than seen. Talking of assertion, Sonoro are a professional choir who sing with the full-on force of a cavalry charge and did so in the London concert they gave to launch a new CD called Passion and Polyphony. Works by Frank Martin and James MacMillan almost blew me off my seat with their sheer strength of sound. Impressive if unnerving. And there was a keyboard parallel when Steven Osborne played Prokofiev’s mighty 8th Sonata at Wigmore Hall, as part of a dynamic recital that gave the piano a battering (in the most artful of ways). The oddest and most unexpected dynamism of the week, though, came in a programme of Edith Piaf songs given by the countertenor Adrien Mastrosimone. Countertenors aren’t supposed to do this sort of thing: their world is Handel, Bach and the baroque. But being French, Mastrosimone was raised on these songs and sings them with showbiz panache, sweeping emotion and an uninhibited high camp that had the audience at the London cabaret venue Toulouse-Lautrec on its feet. His programme trawled through the life of Piaf, which was maybe not a role model for Catholics. But as I learned, she was devout – having supposedly been cured of blindness as a child by praying to St Thérèse of Lisieux. It explains a lot about the songs: their interplay of sado-masochism and defiance. Whether they suit countertenors is debatable. But this one makes a case for it.